THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA DAVIS h STATE OF CALIFORNIA DEPARTMENT OF PUBLIC WORKS DIMSIONS OF ENGINEERING AND IRRIGATION AND OF WATER RIGHTS BULLETIN No. 11 /^ ^ Ground Water Resources of the Southern San Joaquin Valley By S. T. HARDING Consulting Irrigation Engineer CALli'ORNlA STATi; PRINTING OFFICE CHAHLKS A. WHITMORE, State I'llnter SACRAMENTO, 1927 '^'''^ LIBRARY UNlVERSilY OF CALIFORNIA DAVIS I TABLE OF CONTENTS. Page CHAPTER I. INTRODUCTION AND SUMMARY 7 Introduction "^ Summary of Main Report 12 Summary of Chapter III — Ground Water in Kings River Area 14 Summary of Chapter IV — Ground Water in Tulare County Areas IT Kaweah River Areas 1" Areas Dependent on Tule River 19 Deer Creek Area 20 White Creek Area 20 Summary of Chapter V — Ground Water in Kern County Areas 20 CHAPTER II. GENERAL DESCRIPTION OF SOUTHERN SAN JOAQUIN VALLEY 23 Data Available on Ground Water 23 Maps Delineating Ground Water Conditions : 24 General Ground Water Conditions 27 Ground Water as a Source of Irrigation Supply 27 ('limate 28 Soils 28 Water Supply ; 28 U!=!e of Surface Water Supply 30 Areas Irrigated 30 Value of Agricultm-al Products 32 Geologj' 32 Quality of Ground Waters 34 CHAPTER III. GROUND WATER IN KINGS RIVER AREA 37 Growth of Pumping from Ground Water 39 Methods of Analysis of Ground Water Conditions 40 Ground Water in the Fresno Irrigation District 42 Ground Water Fluctuations from December 1 to March 1 45 Ground "^'ater Fluctuations Mirch 1 to December 1 47 Ground Water in the Consolidated Irrigation District.. 56 Ground Water Fluctuations December 1 to March 1 57 Ground "Water Fluctuations March 1 to December 1 57 Ground Water in Laguna Irrigation District 62 Ground Water in Riverdale Irrigation District 62 Ground Water Supplies in Kings River Areas not Directly Served by Canals — 63 Ground Water in Foothill Irrigation District 66 Ground Water in the Alta Irrigation District 67 Ground Water Fluctuations from December 1 to March 1 67 Ground Water Fluctuations March 1 to December 1 ; 68 Ground Water in Area Under Kings County Canals 73 Lemoore Canal Area 74 Last Chance Area 75 People's Ditch Area . 75 Ground Water in Valley Trough Areas Along North Side Channels of Kings River 76 Cuthbert-Burrell Area 76 Stinson Irrigation District 77 Crescent Irrigation District ' 77 .James Irrigation District 77 Summary 78 Grcjund Water in the West Side Area from Tulare Lake to Mendota 79 Ground Water in the Tulare Lake Area 80 CONTENTS— Continued. Page CHAPTER IV. GROUND WATER IN TULARE COUNTY AREAS 83 Ground Water in Kaweah River Areas 84 • Ground Water in the Main Area of Kaweah Delta Covered by Canals Divert- ing for Land.s Below Venice Hills 88 Ground Water in the Areas Covered by Canals Diverting for Lands Mainly Above Venice Hills 92 Ground Water in the Area West of Lindsay-Strathmore Irrigation District Toward Which Ground W^ater Slojies from Kaweah Delta 9:! Ground Water in the Area of Lower Kaweah Delta Outside of Areas Covered by Canals 9"> riround Water in the Area of Lindsay-Strathmore Irrigation District 9(> Ground Water in Areas Dependent on Tule River for Their Water Supply !tG Ground Water in Main Tule River Area Including the Areas Within Which Some Lands Receive Canal Irrigation from Tule River OS Ground Water in Area on North of Tule River Delta 102 (iround Water in South Tule Area lO.T Ground Water in Outer Tule River Area 10:! Ground Water in Deer Creek Area — 107 Ground Water in White Creek Area 110 CHAPTER V. GROUND WATER IN KERN COUNTY AREAS 115 Rates of Pumping Draft 115 Ground Water in Area Above the East Side Canal 116 Ground Water in East Side Canal Area 121 Ground Water in Main Canal Area South of Kern River 124 Ground Water in Areas North of Kern River 125 Ground Water in Rosedale Area 125 Ground Water in Shatter, Wasco and McFarland Area 131 Ground Water in Northern Kern County Area 142 Ground Water in Pioneer Canal Area 142 Ground Water in Valley Trough Areas South of Tnlare Lake 14:! I LIST OF FIGURES. Page Fig. 1. Growth in u.«c of power by agriculture for pumning In Dinuba, Fresno and Selma Districts of San Joaquin Light and Power Corporation 38 Fig. 2. Comparison of ground water levels 1907-1926 in Fresno Irrigation District "^^ Fig. n. Relation of change in level of ground water during December, January and February to rainfall during the same months in Fresno Irrigation District ""' ]<'ig. 1. Relation of volume of water diverted by canals to change in level of ground w;iter in areas under canals in Fre.sno Irrigation District IS Fig. ."■. Hydrographs of typical wells in Fresno Irrigation District 52 Fig. (■>. Relation of change in level of ground water during December, January and February to the rainfall during the same months in the Consoli- dated Irrigation District ^'^ Fig. 7. Relation of volume of water diverted by canals to change in level of ground water in areas under canals in Consolidated Irrigation District- .''>;i Fig. S. Hydrographs of typical wells in Consolidated Irrigation District CO Fig. "J. Change in level of ground water since November, 1921, in shallow w^ells of James Irrigation District and wells in adjacent areas in the Fresno Irrigation District *' ' Fig. 10. Relation of change in level of ground water during December, January and February to the rainfall during the same months in the Alta Irriga- tion District ''^ Fig. 11. Relation of volume of water applied in irrigation to change in level of ground water during period March 1 to December 1, in areas in Alta Irrigation District 70 9 Fig. 12. Hydrographs of typical wells in Alta Irrigation District Fig. 13. Relation between canal diversions and change in level of ground water in Lemoore Irrigation District In 1925 75 Fig. 14. Relation of canal diversion to change in level of ground water in area .sei-ved by Last Chance Canal in 1925 70 Fig. 15. Hydrographs of typical wells in main area of Kaweah Delta 90 Fig. 16. Hydrographs of typical wells in outer areas of Kaweah Delta 94 Fig. ]7. Hydrographs of typical wells in Main Tule River Area 10hs of typical wells in Deer Creek Area 108 Fig. 20. Hydrographs of typical wells in White Creek Area 112 Fig. 21. Hydrographs of typical wells in the area above the Bast Side Canal__ 118 Fig. 22. Hydrographs of typical wells under East Side Canal 122 Fig. 23. Hydrographs of typical shallow wells in main area south of Kern River 126 Fig. 24. Hydrographs of typical wells in the Rosedale Area 127 Fig. 25. Relation of water applied in irrigation from Isoth canals and wells to change in level of ground water in Rosedale Area I'I'i Fig. 26. Relation of water applied in irrigation from both canals and wells to change in level of grf>und water in Shatter, Wasco and McFarland Areas 135 I'^ig. 27. Hydrographs of typical wells in Shafter and Wasco Areas 138 Fig. 28. Hydrographs of typical wells in McFarland Area 14 Fig. 29. Hydrographs of tyiiical wells in Goose Lake Slough and Buttonwillow Areas 144 LIST OF MAPS. Map 1. Ground water contour.s, U. S. G. S. datum, as of October, 1925, in southern San Joaquin Valley In pocket Map II. Depth of ground water, as of October, 1925, in southern San .loaquin Valley In pocket Map III. Lowering of ground water for the five-year period 1920-1925 in .southern San Joaquin Valley In pocket ,1 CHAPTER I. INTRODUCTION AND SUMMARY. Introduction. The Southern San Joaquin Valley, as the term is used in this report, includes the portion of the San Joa(iuin Valley from the San Joaquin River south. The availalile local surface and underground water supplies are more completely utilized in this area than in other parts of the San Joaquin or Sacramento valleys. The rapid increase in the pumping- of ground water in recent years makes it desirable to con- sider the extent of the ground water supply. Most of the Southern San Joaciuin A^alley is underlaid by ground water within depths which make pumping profitable. The data assembled for this report shows that of the total area of 1,370,000 acres irrigated in this area, 800,000 acres secure all or part of their water sujiply by pumping from wells. For about 400,000 acres the entire irrigation supply is secured from wells, for the remaining 400,000 acres the pumping supplements supplies secured from canals. The Southern San Joaquin Valley represents one of the most liighly (levelopi^d agricultural sections in the state. The area irrigated is over one-fourth of the total for the state. The value of the agricultural products is probably an even larger proportion of the total value of irrigated crops. All classes of irrigation practice are represented, varying from citrus, vineyards, deciduous orchards, melons, lettuce, cotton and cereals to the crude flooding of pasturage. Owing to the limited rainfall in the valley areas practically all agriculture depends on irrigation, dry farming being limited in extent and uncertain in results. The gross area of valley lands in the Southern San Joaquin Valley is 4,000,000 acres. There is in addition abovit 350,000 acres of adjacent higher i)lains areas suited to irrigation if water can be made available. Present irrigation represents less than one-half of the valley land of a quality suited for irrigation. AVitli the available local sources of Avater supply very largely utilized for the irrigation of present areas, the importance of detailed study of the present use and the opportuni- ties for increased use is apparent. The complete use of surface sources of supply is being planned where opportunities for additional develop- ment, largely through storage, occur. This report is limited to a con- sideration of ground water supplies and use as the full utilization of such supplies is as desirable as is the use of the surface streams. How- ever, while all increases in use for which local ground water supplies are available is desirable, it is equally desirable that additional develop- ment should not be undertaken unless a water supply for its permanent support is available. Canal irrigation l)egan over fifty years ago; i)umi)ing is a relatively recent development. In the earlier period of use of ground water little effect on the ground water elevation was noticed as the draft was small in proportion to the total areas affected. In recent years the lowering of the griumd water in some parts of the area has become serious and doubts have arisen regarding the permanence of the supply. 8 Departnienl of Public Works. This iTpoi-t is tlic result of an eft'oi-t to detorinine the relation of present use to the available supply. Gi-ound Avater supplies are local in character. The pjreater portion of this i-eport consists of a detailed discussion of the ground water con- ditions in the different parts of the area. Kuch discussions are based on the available ground Avater records Avlilcli cover periods varying from one to six years iji the different parts of the area. The ])resent discussions are of the nature of a progress report and any conclusions expressed are necessarily subject to modification as records covering longer ]ieriods of time become available. Well measurements should be continued and extended so that sufficient data may be accumulated for draAving final conclusions. It is considered that the general eon- elusions stated are ade<|uately suj)ported by the present records. Fuj'ther experience may result in changes in some of the details of the conclu- sions regai'diufiT local areas. The extent of the dependeiice on the use of ground AvattM" in this area makes it essential that the collection of ade- quate records be continued in ordei- that the effects of present use may be observed and tlie limits of feasible deA^elopment more definitely detei-mined. AVhile ground Avatei- may extend generally under relatively large areas, it moA'es slowly and the replacement of Avater that has been removed by pumping takes place similarly sloAAdy unless streams or canals are close at hand. It is because of these conditions that a com- parison of the average sujiply available and the total draft for a large area gives little indication of the conditions in different parts of the area. The greater portion of this report rei)resents an effort to present the local conditions in the different parts of the Southern San Joa(piin A^alley. Tn this introduction it is only desired to present the conclu- sions reaclied. The support for the stalonents made Avill be found in the detail di.scussion in the main portions of the report and is not i"ei)eated here. The total mean annual stream fiow tributary to the Southern San Joa<|uin Valley is .'^.^JOO.QOO acre-feet. Th(^ ])resent irrigation develop- ment from both canals and pumping represents one acre irrigated for each 2.4 acre-feet of mean annual Avater supply. This is a more com- ]>lete use of local Avatei- su])plies than is found in any other similarly large part of the San Joaquin or Sacramento valleys. The only local Avater supplies unused in the Southern San Joaciuin Valley are the excess stream fioAv in years of more than normal precipitation. There has been practically no unused run-off from 1923 to 1925, inclu- sive. Only about fifteen per cent of the total aA'erage run-off now escapes from this area through the San Joaquin River or is lost as excess cA^aporation from Tulare Lake. Plans are being made for works AA-hich Avill result in the use of much of this excess. Practically all water that can be used Avithout storage has been and is being utilized for some type of irrigation. The area as a whole has been and is utilizing its locally available supplies. Further development will be as largely by imjirovements in present ])ractices as it Avill be by the additional use of local supplies now unused. Local supplies can never supply the aA'ailable irrigable area as the total locally tributary mean annual streaiu Aoav is less than one acre-foot per acre of irrigable land. Ground ^Yat€r Kcsoia is the sum of smaller areas in different parts of the Southern San Joa(|uin Valley and is all in areas outside of those receiving canal service. Further increase in pumping will result in an extension of these conditions to other areas as only a portion of their gross area is now irrigaterl. An attempt to iri-igate additional lan.ds hy pumping in many areas now' partially served by canals will result in some cases in a draft in excess of the supply with a consequent progressive ground Avater lowering. Much of the area of 180.000 acres which it is considered is drawing ou its ground waters at a rate in excess of its supply has possible means of relieving this condition by changes in the present use of the local stream flow. These consist of areas where by storage or transfers in place of use of present canal diversions, water may be made available from canals to replace present pumping directly or where the irrigation by canals of new areas will make available additional ground water sup])lies for present pumping. Such means may relieve the present ovei'draft in about one-half of this area of 180.000 acres. From one-half to two-thirds of the area of overdraft is pumping fi'om wells that are distant from active local sources of ground water replenishment or in areas where local supplies are already overtaxed. Only continued lowering of the ground water can be expected in such areas if present conditions of use and supply continue. These areas are not confined to any one part of the Southern San Joaquin Valley but occur on both the east and west sides of the valley and in each of the tliree main divisions discussed, nameh% the Kings River areas, Tulai-c County and Kern County. In some areas distant from local streams of arie(|uate size tlie irrigation of only a small per cent of the gross irrigable area has resulted in progressive ground water lowering. Other areas are above the lands to which the streams' flow is diverted and in consequence receive a limited replenishment which has already been -drawn upon in excess of its extent. Due to the large areas of irrigable land not now developed much opportunity for additional pumping exists in nearly all areas. In the areas already overdeveloped much good land remains on which the owners may drill wells and secure satisfactory rates of discharge. Under the system of rights to the use of ground water now in use in California each overlying land owner has an equal right to secure ground water in proportion to his needs. Additional development would only result in an increase in the rate of lowering. Such addi- tional development has occurred in the past whenever the prospect of favorable crop prices has resulted in an increased demand for irrigated land. The extent of the ])ossi]ile increased draft with its unfavorable effect on those now pumping in areas of present overdraft is apparent when it is realized that in several of these areas, the pumping for less than one-fourth of the gross irrigable area has resulted in a draft in 10 Department of PnhJic Worls. excess of the supply. In some areas now receiving canal service the extent of the combined canal and gronnd water supplies is only sufficient for the irrigation of about one-half of the gross irrigable area atfected. The attempt to irrigate the remainder of these areas would result in similar conditions of overdraft. Much misunderstanding has been found in regard to the relation of the discharge of individual Avells and the general conditions of ground water supply and draft in an area a.s a whole. Because wells can be drilled from which a good rate of flow can be obtained does not mean that the ground water supply is ample or that it will maintain its level under continued use. The discharge of a well depends upon the char- acter of the materials which it {Jenetrates. If such materials are coarse and freely water yielding, a relatively large discharge may be secured with a small amount of drawdown while pumping. The amount of water that can he drawn from a well while pumping is not a measure of the amount of water that moves into the area from Avhatever sources of supply may be tributary to that area. To install pumps having a total capacity in excess of the average rate of replenishment can only moan a depletion of the accumulated ground water within the area. When the pumping draft in any area exceeds the average ground water supply, the draft in excess of the supply is taken from the ground water accumulation under the area. This results in the lower- ing of the ground water, the increase in pumping lift and costs and the replacement of the original pumping e(|uipment by types of pumps adapted to use under the increased lift. The lowering increases both the investment in pumping equipment and the costs of operation. If such lowering continues, the inci-ease in the pumping lift will eventuall}' become so large that there is no longer a iJrofit from pumping. The time required for this condition to be reached depends on the original depth to ground water, the rate of lowering and the profit from the use of Avater. Fortunately nuich of the area in the Southern San Joaquin Valley had ground water at shallow depths before pumping began so that relatively large amounts of lowering may occur before pumping becomes unprofitable. However, the lowering has, in some areas, already been sufficient so tliat little profit remains from pumping for crops of lower value. If overdraft continues, the resulting lowerinu' will cause a grad- ual decrease in pumping as the less efficient and more expensive ])lants cease to be profitable. Such a process will eventually result in the survival of the fittest with a draft reduced to Avhat the available supply can support. IIoAvever. the path to this result is strewn with the wreckage of the farms and homes of those who attempted development and could not survive. Even the survivors gain little beyond mere existence as the ground water is lowered to a point where little profit in its use remains. Fully as large })ermanent usefulness from a ground water supply could be gained by limiting the draft to the amounts which the available supi)ly could maintain without overdraft and lowering. Such a limited draft would enable all pumping to be practiced with smaller lifts and greater profit. Under our existing principles of rights to the use of ground water wlun'e each owner of land overlying a source of gi-ound water sup])ly has an e(|ual right to participate in its use, there is no means by Avhieli the draft can be limited to the (Iroioid Wairr h'csoiirccs. Hoiilhrrn So)) Joaquin Valley. 11 supply, as in all areas in llic Soutlicni San Joacpiin Valley outside of some of those served by canals the ])ly. efforts towai'd limiting fuiiber develoinnent and toward higher stand- ards of practice with eonseciueut reduction in draft for present areas will extend the time before ground water loAvering may result in the al)andoinnent of pum]^ing plants and the d(>crease in the irrigation development of such localities. Ground water is mysterious only Jo such extent as actual information regarding it is unknoAvn. Each locality should s(h^ th.at its ground Avater history is recorded through Avell measurements in order that unciMtainty as to Avhat has occurred and is occurring is not added to the uncertainties of prediction as to Avhat Avill occur. Summary of Main Report. The ex]>erieiU'e in the use of gi'ound Avater in the Snulliei-n San Joacpiin A'alley emphasi/cs certain results, (^ne of these is tliHt ground water Avhich does not have a direct and local source of replenishment A\ ill not maintain a heavy draft without progressive loAA-ering. (Iround watei- movement occurs slowly and in limited amounts. Extensive use of ground water except in areas having such direct sources of supply has resulted in loAvering of the ground Avater in all ca.ses. Di.stant movement, over relatively long i)eriods. in the i)ast has resulted in the accumulation of large amounts of ground Avater under lai'ge areas in the Soulher}i San eToa<|uin Valley. However, Avhen such ground Avaters are draAvn upon to irrigate more than a small fraction of the gross overlying area, the rate of draft exceeds tlie rate of replacement, tlu' ground Avater stoi-age is draAvn upon and loAvering results. Another fact brought out by the cxi)erienee in this area is that on the lai-ger delta areas the principal source of ground Avater supply is the losses from AA^ater diverted from the streams rather than the seepage from the stream channels themselves. One-half the pum})ing is on lands also receiving some canal service. For such lands tlu' ground Avater fluctuates as it is more heavily drawn upon in years of deficient canal supply hut may be restored in years of larger canal use. Of the pumping area for Avhich it is considered present draft exceeds the Ground Wdirr Ursourccs, Southern San Joaquin Valley. 13 £rroiiiul water supply, only a small portion is in areas receiving canal service. As a source of supplemental water sujjply in areas receiving partial canal service, pumping- i'opres(>nts a very effective and desirable type of stoviigv. Where the eanal supplies arc adequate in amount but occur only during a short diversion season, full irrigation of the entire area can be accomplished by such supplemental pumping. Where the total canal supplies are insufficient, permanent development can not support all of the gross area. Another point which the records assembled in the preparation of this report enables to be estimated is the rate of supply required to provide the moisture I'equirement.s of the crops. In many areas the supply received, the area cropped and the resulting eft'eet on the ground water have been observed for several years. These results ])rovide a basis on which to estimate the water consumed by different ci'ops under different conditions. If the ground water is to be main- tained in any area, the average supply received must be equal to the use by the crops and any outward ground water movement. Records to date from different areas indicate as tentative conclusions that in areas of trees and vines having limited ground water outflow, the crop needs for moisture will be supplied by an average annual deliv- ery into the area of about If acre-feet of water per acre of crop. For forage crops an average delivery of 2 to 2^ acre-feet of water per acre of crop may be required. For other crop conditions other amounts of supply are found. The results for diff'erent parts of the area are dis- cussed in detail in the report. Where ground water outflow occurs or where the ground water is close to the ground surface larger amounts of supplj' are required to supply the crops and maintain the ground water. The general ground water contours which represent the elevation and slope of the gron]id Avater table are shown on Map 1. The depths to ground water are shown on Map 2. The extent to Avhieh the ground, water has lowered from 1920 to 1925 for the areas in Tulare and Kern counties for which records covering this period are available are shown on Map 3. The details regarding these maps are explained in Chap- ter II. The ground water is discussed separately for three divisions of the area. These are the Kings River areas, the Tulare County areas and the Kern County areas. Each of these three areas are relatively dis- tinct in their ground water supply and use. Within each area, the different localities also have distinct ground water conditions and each area is further subdivided for detailed discussion. In considering iliese sub-areas, it should be kept in mind that the discussions of the T-elation of surface water supply and ground water fluctuation are based upon the records of from one to six years. Altered conditions in adjacent territory, from those obtaining during the period of record may effect the relation here discussed. However, a stud}^ of the avail- able data discloses no reason to expect large changes. Also it is de- sired to point out that the discussions apply to average conditions in eacli sub-acrea and may not express the true relation in each individual part. ]4 Department of Pul)tie Works. Summary ok Chapter III. GROUND WATER IN KINGS RIVER AREA. The Kings JJiver area iiieliulcs those areas whose ground water is derived mainly or Avholly from Kin Joaquin Valley. 17 West Side Areas. West of the valley troiigli extending from Tulare Lake to Mendota is a gross area of 250,000 acres, about one-eighth of which is now irrigated from local deep wells. These wells vary from 1200 to 2000 feet in depth. Water is drawn only from below depths of about 600 feet. Its qualit}^ is generally fair being better toward the south end of the area than at the north end or in some areas of heavier draft. Availa1)le records do not enable the present ground water levels or the fluct nations under past use to be definitely determined. Tiie gronnd water api)ears to slo})e from the valley trough toward the west under ])resent conditions. The soiu'ces of ground water replenishment are uncertain ; the supply must, of necessit}', come from a relatively distant source. In other areas remote from sources of ground water supply, the ground water has been found to be sensitive to heavy draft. With only one-eighth of the area irrigated, lowering appears to be occurring. 1'lie conditions are favorable for an overdraft on the underground waters to develop. Owing to the depth of tlie wells required in this area, ground water development is necessarily expensive. Tulare Lake Area. There has been much activity in the installation of deep wells recently in the Tulare Lake area. In wells formerly artesian, water now stands thirty to sixty feet below the ground surface and pumping lifts, including the drawdoAvn, exceed 100 feet. Gas usually occurs in the deeper water. The quality of the water from some wells is not as good as is desirable. However as the areas supplied will receive canal service in years of adequate stream flow and may be submerged at times when Tulare Lake fills, soil in.iury from the use of ground water is not considered probable. The source of supply of these deeper wells is outside the area of Tulare Lake. The source has not been definitely traced. The supply may come from more than one of the tributary streams. Owing to the distanee of movement and fineness of the materials, these wells would be expected to be relatively sen.si- tive to heavy draft. Summary of Chapter IV. GROUND WATER IN TULARE COUNTY AREAS. The four streams in Tulare County in both the order of their size and of their location from north to south are the Kaweah and Tule rivers and Deer and White creeks. The ground water conditions for the areas dependent on each of these streams are discussed separately. Kaweah River Areas. The mean annual run-off of the Kaweah River is estimated to be 440,000 acre-feet. The total gross area considered to be dependent on the Kaweah River for such water supply as it may receive is 365,000 acres of which 175,000 acres are now irrigated. This represents an acre of crop for each 2.5 acre-feet of mean annual stream flow. Ground 2 — 4707C 18 Department of Puhlic Works. water records covering the ]artj;er part of the area are available since 1917. Records -were begun in the remaining area in 1920. For the eight years from 1917 to 1925, the ground water over the whole Kaweah River area has lowered an average of 1.6 feet per year. The stream flow for this period has averaged 78,000 acre-feet per year below normal. For the gross area of 365,000 acres, the ground water lowering rein-osents an amount of water about equal to the deficiency in stream flow. For the area as a whole the present development appears to require the full average supply. The development of any material part of the remaining half of the gross area which is not now irrigated would result in an overdraft on the .supply. While as a whole present use appears to about e(iual the average water supply, the draft and u.se in the ditferent parts of the area are not balanced. An excess canal supply is secured in some areas, in other areas pumping exceeds the average replenishment. In the main area covered l)y canals diverting for lands below Venice Hills, the ground loAvering in the five-year period from 1920 to 1925 has been less than five feet in the areas receiving canal service of regular character. The lowering in areas of irregular canal service has been about ten feet. In much of this area the ground water would be expected to rise closer to the surface than is desirable in years of normal stream flow. For the whole area the average lowering was about twelve feet from 1917 to 1925. For the upper areas above Venice Hills, on the north side of the river, recent increases in pumping appear to have resulted in a draft in excess of the supply reaching the parts of the area more distant from direct canal use. On the south side of the river, in an area of 3000 acres of which four-fifths Avere developed, a lowering of fifteen feet occurred from 1920 to 1925. Although some canal service is secured the present rate of draft appears to exceed the present sources of supply and continued lowering is to be anticipated. For the whole area the irrigation of one-fourth of the gross area resulted in an average lower- ing of ten feet from 1917 to 1925. There is a gro.ss area of 20.000 acres of which 7300 acres are now irrigated west of the Lindsay-Strathmore Irrigation District toward which the ground water slopes from all directions due to tlie lowering of the ground water that has occurred under the heavy local draft. In the portion of this area toward which the ground water slopes from the main Kaweah River area the ground water lowered twenty feet from 1917 to 1925. The total lowering to date exceeds eighty feet in some parts of this area. The greatest lowering has occurred within five miles of areas along Outside Creek in which the lowering has been less than five feet during the deficient years from 1920 to 1925. The exces- sive lowering does not ap]iear to liave established ground water move- ment into the area to a sufficient extent to supply the present draft as the lowering was greater in 1925 than that in either 1918 or 1919 although the stream flow in 1925 was laroer than that in cither of the earlier years. There is an area of 95,000 acres, of which 15,000 acres are irrigated from wells, that is within tlie general area of the lower Kaweah Delta but outside the area served by canals. The lowering that has occurred in this area is generally pi'oportional to the amount of the local draft. (J round Wi'Irr h't soiincs, Soutlicni San Joaquin Valley. 19 Little lowering has occvirred even in the dry years where little pumping is praetieed. Whore much pumping has occurred a lowering of several feet per year is shown. The experience in this area is an additional illustration that ground water movements from distant sources occur relatively slowly and that areas in the direction of the ground water slope from diret-t soui-ces of supply may be unable to support a pumping draft suliticient for the irrigation of more than a small part of the gross area. The irrigation of one-sixth of the gross area resulted in an average lowering of sixteen feet frOm 1917 to 1925. Areas Dependent on Tiile River. The mean annual run-off of Tule River is estimated to be 132,000 acre-feet. About 68,000 acres are irrigated in the gross area of 204,000 acres whose water supply is dependent upon Tule River. This repre- sents an acre irrigated for each two acre-feet of mean annual run-off. For the five years 1921 to 1925 the average stream flow has been 90,000 acre-feet per year. The average lowering has been 11.5 feet for the same period. For the whole area the ground water storage represented ])y this lowering would be larger than the shortage in stream flow in these years indicating some overdraft for the area as a Avhole. As in the case of other delta areas, the conditions vary in the different parts of the Tule River Delta. The main area of the Tule River Delta includes the lands receiving canal service. It represents the lands sufficiently near Tule River and its canals to have more definite sources of water supply. Of the total area of 77.000 acres about one-third is irrigated. The ground water lowering from 1921 to 1925 has averaged five feet in the part of the area having the heaviest pumping draft but also receiving the largest canal supply. The middle portion of the area lowered ten feet with a slightly smaller draft. The outer portion lowered twelve feet under a much lighter pumping draft. These results indicate the need for direct sources of supply witliiii each area if much pumping draft is to be maintained. There is an area north of ihc Tule River Delta toward which the ground water now slopes from the Tule River Delta. Of the gross area of 21,000 acres nearly one-half is now irrigated from wells. The present ground water slope is the result of the excessive lowering that has occurred in this area. The lowering in 1925 was larger than that in earlier years of similar stream flow. A general average ground water lowei'ing of about four feet per year can be expected in this area. On the south of the main Tule River area are 7000 acres of which one-eighth is now iri-igated. An average loAvering of eiglit feet has occurred in tlic last five years. Tliis is less than the average lowering in otiier outer Tule Rivci- areas. Any larger draft would be expected to result in an inereasetl rate of lowering. On the outer part of the Tule River Delta is an area of 97,000 acres of wliieh one-fourth is irrigated from wells. An average rate of draft of al>out one-half aei-e-foot i)ei- aere of gross area resulted in a lowering of about twelve feet from ]!»21 to 1925. In the upper i)art of this area in 1921 the draft was similar to that in the part of the main area receiving canal service; the ground Avater lowering was six times as 20 DfpiirlDU'iil of I'lthUc WorU. largo as in the canal area. This eomparison illustrates the greater sensitiveness to draft of sueli outer a)-eas that do not have direct local sources of ground water supply. An average ground water lowering of ahout two feet per year is to be expected in this outer area as a whole under existing conditions of use. Larger amounts of lowering are to be expected in areas where more than one-thir(] of the gross area is su]i]ilied by putin)ing fi'om wells. Deer Creek Area. The (>sliiii;it('d iiiciii ;iiiiiii;il niii (iff of Dccf ('reck is ID. 000 acre-feet. This is the only soun-c of supjily I'oi- a i>ross area of lOli.OOO acres of which 1!>, (»()() aci'cs oi- eighteen per cent ai'e now in-igated. Tiiese figures include the area in the Terra J^ella Irrigation i^istrict. The ground water records indicate that even this small proi)ortion of development will result in an average ground water lowering of al)out 2.5 feet per >'ear. The present pinn])iiig draft is about twice tlu^ mean annual flow of Deer Creek. White Creek Area. The estimated mean annual run-off of "White Creek is 6300 acre-feet. An area of 104,000 ticres in the southern part of Tulare County is dependent on White Creek foi- sucli ground water supjilics as it may receive. About one-Hftli of this ai'ea is now irrigated from wells. From 1921 to 1925 the ground water has lowered an average of twelve feet, the lowering being as large as thirty feet in areas of concentrated draft. The total i»iunping draft in 1925 was eight times the estimated mean annual run-off of White Creek. Further increase in ai'ca irrigated by pumping from wells in this area can only increase the pre.sent rate of gi'ouud water lowering. SUMM.MJV OI' ClIAl'TEi: A'. GROUND WATER IN KERN COUNTY AREAS. The irrigated areas of Kern Comity include a wide variety of condi- tions of sujjply and draft. Kern River has an average annual run-off of al)out 800,000 a^re-feet per yeai". The areas receiving the larger amounts of canal service practice very little pumping. Canal use has resulted in the need for drainage in much of such areas. Other areas are distant from active sources of ground water supply and show ground water de})leti()ii under i)re.seut conditions of use. The conditions can be more readily discussed by separate areas. Areas Above the East Side Canal. This area lies south and east of Rakersfield in the vicinity of Arvin. The i-un-ott' of Caliente Creek is considered to be the only source of ground water supply for this area. This ruu-otf is estimated to be an average of 35,000 acre-feet per year. Of the' gross area of 55,000 acres about 17,000 acies are now irrigated from wells. The present pumping draft for the thirty per cent of the total area that is irrigated appears L (Innind W'uhr lu saincrs, Soiillni-ii S«iii Joaquiii Valley. 21 in he fully (m|umI to tin' (iv;iilal)h' .siip|>ly. A maxiiunm tri'ouiid water lo\v('rin}i- of tAvouty iect has occurred in the years lUliO to 1925 in the area of heaviest pninpins: draft. An increase in the area irrigated can only he expected to result in ;iii increase in tlie rate of ground water lowering'. Area Under East Side Canal. This area includes 8.S,r)()() acres of whicli al)out one-half is irrigated. A larger area is supplied entiiely from wells than the area receiving canal service. The available records indicate that the present area iri-igated is as large as the present sources of Avater supply can support without progressive gouud watfM- lowering. Main Canal Area South of Kern River. This area includes 162,000 acres of which about one-half is in the Kern River Water Storage District. Past canal use has resulted in a relatively high ground water table over much of the area so that drainage is needed. Owing to the character of the canal supply obtained there has been little development of pumping. A continuation of the past amounts of canal diversion into this area can be expected to maintain a high ground water. Present average rates of diversion exceed croj) consumption of moisture and drainage is essen- tial on much of this area if adequate crop production is to be secured. The physical conditions for pumping are favorable on much of the area near Kern River. Such pumping, in addition to furnishing relief as di-ainage, would also make available additional water supply. Rosedale Area. This area lies adjacent to and north of Kern River. Of the gross ai-ea of -14.000 acres aliout 12.000 acres were irrigated in 1925. About oiu'-thii'd of the irrigated area secures its supply entirely by pumping, (xround water in this area is r<4atively close to the ground surface. The canal su])i)ly has exceeded the crop use in the past and excess eva))oration from moist areas and outward ground water movement have occurred. The ground water lowering that resulted from tin; shortage in canal supplies in 1924 has caused a reduction in the ground water losses from this ai'ea. Ap])arently canal delivery into this area can be deci-eased without shortage in the (!rop supply if the gi'ound water is held at the levels of 1924 and 1925. Shafter, Wasco and McFarland Area. This area extends from the Rosedale area on the south to the north as far as canals from Kern River or Poso Creek affect the ground water conditions. Jt extends from the Lerdo ('anal on the east to the western edge of general ])umping above the valley trough area. The gross area is 181,000 aci-es. The area now irrigated by pumping is 45,000 aci'es. The Mica irrigated from canals varies with the available canal supply from a small acreage to 20,000 acres or more in years of large stream flow. 22 Depart mcui of VnhUc Worl!S. Prior to canal eonsti-uction tlie LTOund water stood al)out ffty feet l)eloAv present levels. The only sources of supply were Peso Creek and such very limited fi^round water movement as may have occurred from the foothill areas to the east. Seepage from Kern lliver does not reach this area. Pu!iipin«- lias Ix'cn extensively developed near Shafter. AVasco and McFarland. The ground water secured is mainly that resulting from percolation losses from the canal use on the hii^her lands. Outward movement of ground water probably occurs to areas to the west. An analysis of tlie available records indicates that the consumptive use of moisture is about 2.0 acre-feet per acre of cropped area and that the outward ground water movement may amount to 25,000 acre-feet per year. These results when applied to the present areas irrigated represent a total requij'cment in excess of the average supplies now received. AVith present development and average water supply condi- tions a ground water lowering of about 1.5 feet per year Avould be expected. Studies of available sources of additional canal su2)i)l\' for this area are being made by the Kern River "Water Storage District. The pre- ceding conclusions are based on the present conditions of canal delivery. Northern Kern County Area. The elfect of Kern River ("anals and Poso Ci-eek does not extend to the nortliern boimdary of Kern ("ount.x'. The only source of supply for the remainiiiL;- area is Rag (4ul(h whose erratic run-off has been estimated as an average of 3500 acre-feet per j'car. The pumping draft in 1921 was estimated as 9000 acre-feet. This has increased since 1921. Ground Mater recoi-ds are not complete in this area but lowering has occurred and can only be expected to continue under existing conditions. Lower Areas in Kern County. These areas represent lands along tin- lower course of Kern River mainly in the valley trough. The Pioneer Canal area receives canal irrigation. Some pumping is developed but additional draft appears f(>asible. In the Goose Lake Slough area about 5000 acres are irrigated, largely from artesian floAv. No present overdraft is apparent in this area. In the Button AVillow area there is little ground water development. Deep wells tlow sufficiently for stock use. ToAvard the north some wells encounter water of poor (|uality. A few wells of good yield have been secured recently at the south end of the area. The generally fine texture of the water bearing materials makes it difficult to secure good yields in parts of the area. There is not much ])innping for agricultural uses in the area south of Tulrire Lake. Some deep wells are in successful use. There has l)een activity in j)umping for duck club use in parts of this area in recent vears. Ground Water Resources, Southern San Joaquin Valley. 23 CHAPTER II. GENERAL DESCRIPTION OF SOUTHERN SAN JOAQUIN VALLEY. This report presents the results of a study of the ground water resources of the southern half of the San Joaquin Valley extending from the southern end to and including the Kings River area. The rapid increase in the use of ground water for irrigation in this terri- tory in recent years, with the resulting lowering of the elevation of the ground water in many parts of the area, makes the study of these conditions an important part of the State's Avater resources investiga- tion. Should these Avaters continue to recede, extensive areas of inten- sively cultivated land dependent upon irrigation will be without a water supply. Ground waters, like surface water supplies, must have a source, the volume of which limits the amount of draft that can be permanently supplied. The measurement of the volume of surface water supplies has been a recognized field of endeavor for over twenty years. Develop- ment of these supplies has been based on the knowledge so obtained. Similar records of ground water supplies have been attempted _ only in recent years although there is the same need for making available information regarding the extent of ground water supplies that there is for surface streams. The physical conditions involved increase the difficulty of determining the extent of ground water supplies. Such difficulty, however, does not remove the need for such information but rather increases it, for without such information not even approxima- tions to the supply can be made. The serious nature of the problems now confronting several large sections of the area, and the dropping ground water level paralleling the complete utilization of local supplies, has made it desirable to assemble all the information possible. The great volume of data collected for this report strongly supi)ort the deductions concerning the present condition of this supply and the great danger confronting these com- munities unless cognizance is taken of these conditions so that remedial measures may be undertaken. DATA AVAILABLE ON GROUND WATER. The State Department of Engineering undertook active studies of ground Avater conditions in parts of this area in 1920. Prior to this, some general studies had been made by the U. S. Geological Survey, the results of which are reported in Water Sup]>ly Papers 222 and 398. In 1920, in cooperation with Kern and Tulare counties and other interests, studies of the local Avater resources, both surface and underground, Avere ])egun in these tAvo counties. The results of these investigations Avere ])ul)lished for Kern County in Bulletin No. 9 of the Stale Department of Engineering, and for Tulare County in Bulletin No. 8 of the Division of Engineering and Irrigation; the reorganization of the State's Engineering Department haA'ing resulted 24 1)< paiiiix III (if I'lihlic Works. in the clianire in uaino. T-5cginnin^- in 1!I21, ol)S('rvations of the fluctua- tion of the o'round ■water witliin tlieii- own areas were undertaken by several of the irrigation nnits on Kinirs River. With the filing of the petition for the organization of the Kings River Water Conservation Disti-iet in ]!)24, these records have been before the department in its investigations of this district. Following the completion of the investigations and .'{ mentioned above were based, ground water records have been continued in l)oth Kern aiid Tulare counties by local inlci-ests. In Kern County the Kern Kivcr Water Storage District has maintained i[uite complete I'ccords since its oi-gani:'roiind water for the parts of the area for whicli data is available. The depths shoA\Ti represent the dis- tance from the ground surface to the ground water when the pumps are idle. When pumping the ground water in the wells lowers hy an amount neee.^sary to cause tlie flow of water into the well. This lower- ing while pumping is usually called the drawdown. The actual pump- ing lifts in any area will exceed the depths shown on Map No. 2 by the amount of such drawdown. For usual conditions in this area the drawdown is from ten to twenty feet. Where tight materials are heavily pumped the drawdown may lie forty to fifty feet. In the areas receiving adequate canal service the ground Avater is generally less than twenty feet below the ground surface. In many areas it is within ten feet. Until the dry year of 1924 and the recent increase in supplemental pumping it Avas less than five feet in some areas. The depth to ground water increases generally in the areas away from canals and streams. It is ereater near the eastern edge of the valley Avliere the depth exceeds 100 feet in many areas. In some cases depths a.s large as 200 feet are found. The effect of ground water lowering due to heavy draft is shown in some areas. This is illustrated in the area Avest of Tulare and near Tipton and Earlimart. Depth to ground Avater in much of the valley trough area is not shoAvn on Map No. 2. Most of this area was formerly artesian and Avells floAved. Recent pumping has resulted in the loss of the artesian pres- sure and the Avater in the Avells usually stands beloAv the ground sur- face. IIoAA-ever, the depth to Avater fluctuates during the season and can not be adequately shoAvn on a map representing depths at a selected date. Map Showing Ground Water Lowering. Map No. ;j sliOAVs the ground Avater lowering from the fall of 15)20 to the fall of ]92'5 for those parts of the southern San Joaquin Valley for Avliich the data is available. In the Kings River area observations Avere not begun until 1921 or later in the different parts of the area. In the main canal areas on Kings River the lowering has been less than ten feet and in most of these areas less than five feet for the last four years. Most of this loAvering occurred in 1924. In some outlying areas larger amounts of loAvering have occurred. Map No. 3 shoAAS the lowering in the main pumping areas in Tulare County. The lowering has exceeded tAventy feet in areas di.stant from direct sources of .supply in Avhich heavy pumping is practiced. The conditions resultintr in such loAvering are discussed in detail for each area in C'hai)ter IV. In a fcAv areas no loAverijig occurred. Lines of no fluctuation for 1922 and 1925 are also shoAvn. AVithin these areas no loAveriug occurred in these years. In 1922 the stream fioAV AA'as somcAvhat above normal and in 1925 someAvhat beloAv. In Kern County a loAvering of as much as thirty feet occurred in some of the Wasco and Shaffer area for these A-ears. Less than fiA'c GrouiiiJ Wttid- Ju sources, SouUicrn San Joaquin Valley. 27 foe't loweriii'i' occurred in tlic iiuiin canal-scrvcd areas. Above the East Side Canal the i:round \vatei- lowered as nim-li as twenty feet in the areas of heaviest pniu[)inij-. GENERAL GROUND WATER CONDITIONS. In general the ground water conditions throughout most of the southern San Joaquin Valley are relatively favorable for the securing of ade(|uate yields fi'om Avells of moderate depths. Within the main delta areas of the larger streams, wells of less than 200 feet depth will usually yield discharges of one second-foot or more with drawdowns of less than twenty feet. Such plants have generally nsed centrifugal ])umps set in shallow pits. Many such wells are less than seventy-five feet deep. In areas more distant from the streams where the materials are gen- erally finer in texture the water stands deeper and deeper wells are re(pnred to secure adequate yields. Even in such areas welLs of less than 200 feet deep were formerly frequently used. Present practice tends toward wells of greater depth equipped with deep well turbines. Larger diameter Avells are used and generally larger discharges secured than from the shallow Avells. Such wells generally vary from 300 to 500 feet deep. In some parts of the area such as the valley trough and west side there is little available ground water in the surface materials and even deeper wells are required. These wells may vary from 600 to 2000 feet in depth in different areas. The water stands much closer to the ground surface in these wells than the depths at which it is encountered. Many of the deep wells formerly flowed. Such deep plants cost from !|^8,000 to $20,000 to install and equip. In order to reduce the cost of the water secured they are usually operated nearly continuously, enough land being served in different crops to utilize the discharge throughout most of the year. Very few dry holes are encountered in drilling in any part of the southern San Joaquin Valley. The valley fill varies in the coarseness of its texture but wells in almost all parts of the area will encounter water bearing strata at some depth. Usual well logs consist of alternating strata of sands and clays. The clay or sand strata in adjacent Avells frequently occur at different depths indicating that the materials have been deposited under irregular conditions such as those now in effect along the present surface streams. GROUND WATER AS A SOURCE OF IRRIGATION SUPPLY. The cost of water secured by i)umping is usually larger than the cost of water delivered l)y the canal systems in this area. Where canal service is available it is generally used in preference to dependence on pumping. IIoAvever, canal service in the southern San Joaquin Valley is dependent on the direct flow of the streams, no storage for irrigation having as yet been constructed on the tributary streams. In order to utilize the unregulated stream flow as fully as is feasible, canals have been constructed Avhich are able to secure stream flow only during relatively short diversion seasons. The service under such canals is 28 l)( ixifhnnil of I'lihiu' WoiLs. usually in excess of crop ueeds during: the diversion period in oi'der to build up th(^ jjround water for us(> in the later seasons. In many areas the divei'sions have brouiiht tlie «i'rouiid water sufHci(Mitly close to the surface so that sul)irri in the north. This occurs mainly during the winter montlis and is inadequate to furnish sufficient mois- ture for crops. The agricultural production of the entire area is almost wholly dependent on iri'igation. SOILS. As ill aii\- lai'ue area, much variation in soils occurs. Considered as a whole, the soils are good; for much of the areas the soils are of good texture and di'i)tli. free from alkali and suited to a wide variety of crops. Some lands are undei'lain at small depths with hardpan which affects moisture movement. Other areas are alkaline, some from natural causes and others from the results of irrigation. The results of surveys by the TI. S. Bureau of Soils have been published and are now available over the whole area. WATER SUPPLY. The only sources of ground water supph' entering this area as a whole are the surface run-otf of the tributary streams and rain falling on the overlvino- gronnd surface. The amount of rainfall is so small Gvuund Waicr Resources, SoidlKm Sun Joaquin Valley. 29 that it can be of only very limited, if any, aid as a direct source of ground Avater on the valley area. It is only in areas of high ground water that any moisture may reach the ground water from the direct penetration of the 5 to 10 inches of mean annual rainfall. In the adjacent foothills are areas receiving larger, but still small, precipitation where, due to the rougher topography, some local run-oft' occurs which is absorbed before it reaches definite channels. However, even in these areas the rainfall is relatively light, not exceeding 15 to {)(.'rhai)s 20 inches. Any absorption from such amounts of rainfall wouUl l)e very limited. It is very doul)tful if more than a very small percentage of the rainfall on such areas penetrates below the reach of plant roots. Rainfall is not regarded as a source of any material amount of ground water for the area as a w^hole. The main source of water supply for the southern Ran Joaquin Valley consists of the surface run-oft' of the streams draining the higher adjacent mountain areas. Such mountain areas are mainly granitic and no appreciable amount of absorption or of outward ground water movement can be expected. As the stream gaging stations are located within the areas of the older formations, they are above areas where loss from the stream channel would occur. The measured stream flow can be used with assurance that it represents all of the water supply from its drainage area above the points of measurement. Such stream flow records are available for all of the main streams. There ai-e a number of smaller and lower drainage areas for which only partial or no records are available. Various estimates of the average run-oft' of these areas have been made. Estimates based on the period of actual records on the measured streams and on estimates for those not measured were prepared in connection with bulletins 9 and 3 previously mentioned and in the investigations of the proposed Kings River Water Conservation District. These estimates have been extended to include the measured run-oft' for several more years. The inclusion of the records for the years since Imlletins 9 and 3 were prepared results in a reduction in the average run-off based on the earlier records due to the deficient run-off of recent years. The results are as follows: Estimated Total Mean Annual Run-off from Drainage Basins Tributary to the Southern San Joaquin Valley Based on Period of Direct Measurements. Estimated 7-un-off, • ,^ . „ . aci-e-feet, ' J'eriod of Drainage Basin mean seasunnl measurement West Sifle Strnam.s 10,000 Streams South of Caliente Creek 28,200 Caliente Creek 35,400 Kern Kiver T.'il.oOti 1S93-19''0 I'oso Creek 20,000 ]fl_in5r Other Small Areas North of Caliente Creek__ 11,300 '" Jiag (iuic'h 3,500 White Creek G,300 Fountain Springs . l.OOo Deer Creek IS.yuo 1'iH)_iq9- Tule River l;;2.00(i 1 iiii'l-iqy'- Frazier Valley 500 " "'' L:\vis Creek 1,500 VoUolil ('reek 4,000 K'aweali Jiiver -1I(J,(I00 rurj-] <)•>- ruitoiiuood I'reek 7,000 ' ' " ""' • 'uttunwood Creek to Kings River 7,700 Kings River 1,803,000 lN9')-l!)->-, Areas North of Kings River 7,700 Tntal 3,289,000 ;U) DrptiiiiiK )il of J'uhlic Works. USE OF SURFACE WATER SUPPLY. At the present time nearly all the tributary run-off of surface streams is utilized for irritration ; however, some loss occurs by out- flow thi'ouiili Fresno Slouuli. the only channel loadino; away from tile southern San rJoaiiuiii Valley, or liy evaporation from low areas in which surplus How accumulates or is stored. Kings River is the only stream that contributes to Fresno Slough. Under the recently existing conditions, the average annual amount of outflow from Kings River through Fresno Slough is estimated to have been about 850,000 acre-feet. This varies from practically nothing in years of small run-off to large amounts in years of excessive rainfall. A portion of the run-off of Kings River and the surplus run-off of Kern, Tule and Kaweah rivers collects in Tulare Lake. In past times, Tulare Lake has varied from dryness to a stage that would produce overflow to the north. At present the lake bed is largely reclaimed, the decrease in inflow due to diversions for irrigation making this possible. However, in years of surplus run-off", water in excess of that which can be used will collect in Tulare Lake. JMuch of this can be pumped out for use but owing to the shallowness of storage, evapora- tion losses will be relatively large. Under existing conditions the evaporation loss from Tulare Lake may average about 100,000 acre-feet per annum. There is also lo.ss by evaporation in Buena Yista Lake, into which part of the Kern River empties. This lake is also broad and shallow\ In excess years the spreading of the surplus flow on a wide area toward Tulare Lake results in an increased evaporation loss. The total of all of these losses of water pertinent to present conditions of use is only about 15 per cent of the total mean annual run-off. Future increase in development based on the u.se of the local streams of the southern San Joaquin Valley must depend on improvements in practice rather than on the recovery of water now^ lost. Mountain storage would reduce the volume of the present lo.sses but would not obviate all losses. Thus at the present time 85 per cent of the mean annual run-oft' of the streams is put to use and even with mountain storage much more can not be made available. This use of the existing supplies is probably more complete than that oii any other large area in the state. Mountain storage will result in making possible a much better ^ise of water than is now feasil)le without storage regulation. AREAS IRRIGATED. Lands of the southern San Joa(|uiii \'allcv are iri'igated by canals diveiting water by gravity from tlic .sui-face streams or from wells pumi)ing from the underground walei-s. Some lands use both sources of sui)ply. The area served by canals varies in different years with the volume oh" the stream floAv. The area irrigated fluctuates most widely on thos(> lands having water rights of later [)riority whose water supply is sul)ject to wider vaiiations from year to year. Tlie area served by pumps does not vary witli tlie annual I'un-oiV as does the canal-served areas. The following table gives the areas which are irrigated in a year of normal run-off' in the southern San Joaquin Valley at the present time. Grou7id Water Resources, Southern San Joaquin Valley. 31 These figures are based on data collected iu the preparation of this report and other investigations of the Department of Public Works. Usual area Area receiving Area receiving Total receiving both canal and only pump irrigated canal service pump service, service, area, Area only, acres acres acres acres Kings River area 300,000 335,000 100,000 735,000 West Side area 30,000 30,000 Tulare County areas 80,000 65,000 170.000 315,000 Kern County areas 190,000 10,000 90,000 290,000 Totals 570,000 410,000 390,000 1,370,000 The area now receiving only pump service is over 2J times that irrigated from wells in 1912, as shown by comparison with the area irrigated from wells in the report of the Conservation Commission of that year. These data show that a total area of 1,370,000 acres is now being irrigated in the southern San Joaquin Valley with a total mean annual run-off of 3,300,000 acre-feet. This is equivalent to the irriga- tion of an acre of crop for each 2.4 acre-feet of mean annual run-off. This represents a very complete adaptation of crop practice to existing conditions of run-off and an unusually complete development of the available supply. Complete utilization of the locally tributary stream flow could hardly result in the irrigation of over 1,650,000 acres or about one-half of the available irrigable area. The latest census figures on areas irrigated are those for 1919. These are shown in the following tables. The figures given include small areas outside of the floor of the San Joaquin Valley. Acreage Irrigated Classified by Streams, for 1919 and 1902, Taken from Table 7, Irrigation — California, Fourteenth Census of the United States. Area enterprises to ere Area included capable of Area irrigated, acres Per cent in enterprises irrigating in Drainage Basin 1919 1902 increase 1920, acres 1920, acres Kern River 200,641 116,189 72.7 432,481 299,665 Tulare Lake 70,134 204,860 147,444 Tule River 61,223 175,777 109,412 Kaweah River__ 149,932 356,703 299,474 Kings River ___ 552,601 596,091 7.3 1,052,406 895,263 Totals 1,034,531 2,222,227 1,751,258 Entire State 4,219,040 1,708,720 146.9 7,805,207 5,894,466 The acreage reported for each drainage basin in 1919 comprises all the irrigated land in that drainage basin, including that watered from springs and wells. The figures for 1902 are the only prior census in which the areas were .segregated by drainage basins. The indicated decrease since 1902 on Kings River is due to difference in classification. There has been an actual increase in the area irrigated as well as an improvement in the character of crops on Kings River since 1902. The total area irrigated in 1919 was nearly one-fourth the total of the state. It is interesting to note tbat the increase in area irrigated between 1902 and 1919 has been mueh less than for the .state as a whole because of the arrival at practically a complete utilization of the surface water supply in the southern San Joaquin Valley some time between these years. 32 Drpnrhiiciil of Public Worls. Data regarding the use of same report. The summary ground water in 1919 are also given in the data are as follows: Capacity Flowing ivclls Pumped wells Pumping plants ""f Capacity Capacity J'Jngine pumps J ver- gallons gullotis capacity gallons age Num- per Num- per Num- horse- per feet Dramage Basin ber minute ber minute btj power minute lift Kern River 17 13,850 441 219,674 384 0,676 223,600 47 Tulare Lake 24 8,253 1,100 434,565 906 12,841 1,330,434 59 Tule River 2 251 1,14G 493,272 974 11,329 995,319 4 5 Kaweali River- 3 17 2,13(! 842,0 85 1,734 21,932 876,254 41 Kings River 34 10,000 2,547 1,183,710 2,2S3 6,281 25,426 1,225,007 -■'■ Totals ___ 60 32,371 7,370 3,173,300 78,204 4.651,220 Entire State ___ ],415 297,187 25,401 10,008, 47(1 21,501 386,200 16,773,692 41 The southern San Joaquin Valley had pumping plants which repre- sented about one-third of this class of development in the entire state. Similar Hguri-s for the present date would probably show even a larger proportion ot* the state's ground water development to be in this area. VALUE OF AGRICULTURAL PRODUCTS. Complete statistics are not available on the value of the products from this irrigated area. As the crops grown have a relatively high value per acre and as the production is generally equal to or above the average for such crops, the total value is large. Statistics collected by the Tulare County Board of Trade show an average crop value' at the farm of the agricultural products of Tulare County of about $30,000,000 per year, or an average of nearly $100 per acre from all classes of crops. Tlie irrigated areas in these counties are probably more pro- ductive than other large areas in the state and represent a very important and essential part of the state's agricultural resources. GEOLOGY The present surface of the southern San Joaquin Valley has been formed by the deposit of material brought into the valley l)y the tribu- tary streams. The surface is divided by a ridge extending across the valley formed by the material deposited by King.s River. The amount of this material has been sufficient so that this ridge extends across the valley to meet the slope from the mountains to the west. The elevations on the ridge are higher than those in the Tulare Lake Basin to the south. The other streams have made similar Init le.s.s extensive deposits. Kern River has built a small ridge across the valley. Kern and Buena Vista lakes lying in the trough of the valley in the course of the Kern River formerly received part of the run-off of Kern River. Buena Vista Lake is now used as a reservoir, an embajikment having been built along its eastern side. This embankment has resulted in the reclaiiiatitin of Kern Lake. Tule and Kaweah rivers have not a .sufficiently large flow to have deposited delta.s extending acro.ss the valle\-. The total depth of the valley till is not known; borings to depths of over oOOO feet have not encountered bed rock. This fill has been tleposited in i)ast geologic times, partly when the valley was submerged and i».ir11y iindei- conditions simibir to thos(^ at present. The material Ground Waier Resources, Southern San Joaquin Valley. 33 varies in texture from erravels and eobbles near the point at which the streams debouch from their canyons and along their channels to rela- tively tine and impervious clays deposited in areas remote from the stream channels or under conditions of submergence. These circum- stances result in the ground water occurring under different conditions of pressure at various depths. Artesian wells were formerly obtainable over a larger part of the lower valley floor. From Porterville north, the valley All lies against the "Bedrock'* series on the east. From Deer Creek south to the southern end of the valley there is an area of Tertiary sediments between the recent valley All and the granites. The formations in the west are more irregu- lar, consisting of shales, sandstones and conglomerates. Tlie following general descrijition of the geology of the valley is quoted from Water Supply Paper 398 of the U. S. Geological Survey: "The valley as a whole is a great structural trough and appears to have lieen such a basin since well back in Tertiary time. Since it assumed its general trough-like form, gradual subsidence, perhaps inter- ruption In- periods of uplift, has continued and has been accompanied by deposition alternating at least along what is now its western border with intervals of erosion. This interrupted but on the whole continuous deposition seems to have l)een marine during the early and middle Tertiary ; but during tlie later Tel'tiary and Pleistocene, when presumably the valley had been at least roughly outlined by the growth of the Coast Ranges, fresh-water and terrestrial conditions became more and more predominant, until the relations of land and sea, of rivers and lakes, of coast line and interior, of mountain and valley, as they exist now, were gradually evolved. As these condi- tions developed, the ancestors of the present rivers probably brought to the salt and fresh water bodies that occupied the present site of the valley and its borders, or, in the latest phases of the development, to the land surface itself, the clays, sands, gravels, and alluvium that subsequently consolidated into the shales, sandstones, and conglom- erates of the late Tertiary and Pleistocene series, just as the present rivers are supplying tlie alluvium that is even now accumulating over the valley floor. "The very latest of these accumulations are the sand and silt and gravel beds x^eneti-ated by the driller in his explorations for water throughout the valley. They are like the' early folded sandstones, shales, and conglomerates exposed along the flanks of the valley, except that they are generally finer, and are not yet consolidated or disturbed. The gi-eater part, perhaps all of them, accumulated as stream wash on the valley surface or in interior lakes like the present Tulare Lake, but a proportion of the older sediment that is greater as we delve farther back into the geologic past aceunuilated in the sea or in salt bays having free connections with the sea. It is these very latest geologic dejjosits, saturated below the ground water level by the fresh water supplied chiefly by the Sierra streams, that constitute the reservoirs drawn upon by tlie wells, whether flowing or pumped, throughout the valley. "The ehemicai composition of the ground waters, as well as their occurrence and accessibility, is related to the geology. Where the 3 — 4707C 34 Department of Puhlic Worka. valle.y alhiviuiii is derived from tlm C'retaeeons and Tertiary beds of the coast ranges, rich in f»ypsuiii and other readily sohihle minerals, the o-round waters contain larji'e quantities of the salts. Where, on the other hand, the alluvium is derived from the grranites and metamorphic rocks of the Sierra, wliose potassium, sodium, and calciinu compounds are in the form of diffictdtly s()lul)le silicates, the ground waters uiuler ordinary conditions contain very little of these salts." The Kinjsj.s River ridge is considered to separate the ground water of the San Joaquin Valley into two areas, that to the south heing, prac- ticall>', if not entirely, a closetl basin. Tlie ground water contours on Map No. 1 show a similar ridge or division in the ground water to that of the ground surface. The same nature of direction of slope of the pressure levels of artesian wells is also indicated by the available data. While available records do not indicate the pressure levels from wells sufficiently deep to represent the full valley cross section, those from all depths from which the ground water has as yet been used indicate a similar character and direction of the' ground Avatei- slojie. It appears logical to assiune that any outward northward ground water movement from the area south of the Kings River ridge that maj'' occur is of such small amount that it may be neglected in a consideration of the ground water supply and that the area under discussion in this report is for practical purposes a closed basin. QUALITY OF GROUND WATERS. Over much the larger portion of the southern San Joaquin Vallej^ the quality of the ground water is good. For waters secured from the formations derived from the ('oast Range or from the older materials on the east side, the ((uality is variable. In some areas waters vary in (juality at different depths. A detailed discussion of the quality of the ground waters is included in AVater Supply Paper 398 of the U. S. Geological Survey based on analyses made in 1910. Analyses were nuide in Kern County in 1920 in connection with the investiga- tions of the Division of Engineering and Irrigation. Results of analyses made by private investigations have also been available. In order to supplement available data and make them more complete, about 30 samples, mainly from deep wells in the valley trough and west side areas, were analyzed in the preparation of this report. Almost without exception waters from the recent valley fill on the east side of the valley are of good quality. These materials are derived from the granites and schists of the Sierras. The surface run-off from these same areas is relatively free from mineral constituents. Occasional!}^ water from a shallow well in an area of alkali concen- tration may show high alkali content; in general east side waters from all depths can be used for irrigation Avithout concern regarding their quality. In the southern portion, however, the older Tertiary forma- tions extend into the valley sufficiently far so that some wells receive their supply through such materials. This water contains more impuri- ties and sometimes is not .suitable for irrigation. These waters are characteristically high in calcium sulfate or gypsum. _ Water contain- ing a larger amount of such salts can be used without harm than waters containing the sodium salts. However, in some instances harmful results occur from irrigation with these waters. In the area east of Ground Water Resources, Southern San Joaquin Valley. 35 Bakt'i'sfield along Ihc Mesa where sudi waters are encountered, it has been found that tlie (|nality of the water is improved if the upper strata are shut off. Conditions are more variabh> in the vaHey trougli and west side area than on tlie east side. In Water Supply Paper 398 the axial and west side waters were distinguished as to quality, the west side waters being characteristically high in sulfates and the axial or trough waters, while lower in sulfates, were higher in bicarbonates and chlorides. At the time of the field work (1910) on which this paper is based, deep wells were not available on the west side area north of Tulare Lake nor in the western part of Tulare Lake, so that the data apply to the shallow west side wells. Deep wells are now in use on the west side area extending from Mendota to Tulare Lake. These wells range from 1200 to 1600 feet in depth in the northern portion of the area and increase to 1800 and 2000 feet in depth within the bed of Tulare Lake. The use of such wells is recent and adds to the data of Water Supply Paper 398. In the area west of the vallej^ trough, the waters from all deep wells sampled contained less sulfate than that found in the shallow wells. The amount of the sulfate was higher than in the axial or trough wells, which may indicate some mingling of water from different depths. The materials encountered at lower depths in such wells consist of granitic sands containing mica similar to that secured in east side wells. The character of the material and the quality of the water indicate that the water in these deeper wells may be derived from east side sources. These wells are perforated only below depths' of 500 to 600 feet, indicating that the high sulfate water was probably considered to extend to that depth by the well drillers. That these conditions extend almost to the west edge of the valley is shown by a sample from a deep well on the Chaney Ranch in Sec. T). T. 15 S., R. 13, which contained no more sulfate than wells near Mendota. The waters from the northern part of the west side area contain amounts of sodium, bicarl)onate and chloride which inakes their con- tinued use of doubtful value. Several wells have been in use for a number of years but no definite injury from the use of these waters has been observed. The samples collected show a larger amount of sodium chloride or common salt in the wells in the noi'thern part of the area than in the southern. Samples from the southern half of the area, except from localities of heavy draft, showed water of suitable quality. Water from deep wells in the northern and western portion of Tulare Lake shoAved a \evy low sulfate content, the sulfate being )uuch lower than that in the deep wells in the west side area. The bicarbonate content was larger and the chloride similar to that of adjacent west side Avater. Those waters are moi-e nearly like those found in th(> valley ti-ough along Fi-esiio Slough Ihan the west side waters. The alkali content of tliese waters is largcn- than is desirable; however, as they are used on lands that receive irrigation from surface sources in sea.sons of favorable run-off, proba])ility of their injury is minimized. Along Fresno Slough, deep wells are in use by I)oth the James and Stinson Irrigation districts as a part of their water suply. Additional deep wells are also used by individuals. The water from these wells 36 Department of I'nhlic Works. shows fairl}- large amounts of liicarliouate and chloride with little sulfate. The continued use of these waters alone as a source of supply would probably eventually result in soil injury. All use is, however, as a partial supply, other water being secured either from canals or from other wells. South of Tulare Lake the waters from deep wells were found to be suitable for irrigation use, except in a portion of the lower and western part of the area. This area is inai-kextends on the north to the San Joaquin River and on the south to tlu; Kaweah River areas and Tulare Lake. It is bounded on the east l)y the Sierra foothills. On the west it extends beyond the valley trough as far as pumping has been practiced. The boundaries are fairly definite except in the vicinity of Tulare Lake and Avest of tlie valley trough. Records of ground Avater fluctuation over this area are available for varying periods in the different parts. Detail records for the past four years are' available in the Alta, Fresno and Consolidated districts. Less extensive records are available for the other parts. Also various scattered records have been secured in earlier Acars. The ground water contours shoAvn on Map No. 1 indicate the direction of slope of the ground Avater. The maximum movement of ground Avater is in the direction at right angles to the ground water contours. Map No. 1 shoAvs that a rather narrow area at the north drains toAvard the San Joaquin River. In the upper iiortion of Kings River AAdiere the river occupies a deep channel Map No. 1 sIioaa's a slope toAvard the river channel from both sides. Westerly from Kingsburg the ground Avater contours show a change. The contours here shoAV a slope away from the river as though the river Avere running on a ground Avater ridge. This indicates that in this section AA^ater percolates from the riA'ei" chaiuiel and spreads outAvard into adjacent areas. Map No. 1 shoAvs that this conditio]! folloAvs both channels of Kings River after it divides in the Aacinity of Summit Lake. The ground Avater contours shoA\- a slope both to the north and to the south from this diAnde, simibar lo the sl()])e of tlie ground surface. For the purpose of discussing the available ground Avater, it may be considered that the Kings River area is a closed basin. The extent of any outAvard ground Avalei* movement is so small that for practical ])nri>oses the l)j)sin can be considered as closed. Outward movement )o Ihe west is impr()l)able : the materials are rather fine, the slope flat and the Coast Range Mountains are in the way. Deeper ground water nu)vement to the north luis been discussed in Chapter T under Geology with the conclusion that it is either absent or very limited in amount. Some movement southward into the Tulare Lake area may occur but this is within the general basin area. Movement to the south of Tulare Lake does not occur as a reverse ground water slope from the south toAvard the lake is encountered. Therefore it is assumed that the sup])ly and draft of the ground water in the Kings River area as a Avhole can be treated Avithout alloAvance for material outAvard movement. The ground water supply of the Kings River area is derived almost 38 Department of PuUic Works. Power consumed by agriculture. o (0 S o a E o o o Q. 918 1919 1920 1921 1922 1923 1924 192J Number of consumers of power by agriculture. 1500 1000 500 /y Z' A / ^ ^ ^ / f^ — / Oj f/ / if\C^ / <: ^'^ ^ ^ 1a fres^^ o»&^l^ ^ ?^ / 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 FIG. 1. Growth in use of power by agriculture for pumping in Dinuba, Fresno and Selma Districts of San Joaquin Light and Power Corporation. L Ground Water Resources, Southern San Joaquin Valley. 39 entirely from the run-off of Kings River. The run-off of adjacent small drainage areas is included in the discussions but its amount is relatively very small. Additions to the ground ^vater occur mainly through' percolation after diversion for irrigation rather than by losses from the stream channel itself. GROWTH OF PUMPING FROM GROUND WATER. The increase in the use of ground water in the Kings River area has been very rapid in recent years. Such pumping constitutes the entire .supply for about one-sixth of the area now irrigated and the partial supply for an additional two-fifths of the area. Nearly 60 per cent of the area irrigated receives some ground water supplies. Of the areas lying to the north of Kings River the Fresno Irrigation District has 30,500 acres whose irrigation is .supplied entirely by pumping from the ground water. Much the larger part of the remaining 163,400 acres under canal service is equipped more or less completely with auxiliary well service. It is estimated that there are 3500 pumping plants in this district. In the Consolidated Irrigation District 44,000 acres are reported as receiving their entire irrigation supply by pumping from wells. The 81,500 acres additional which receive canal service are also largely supplied with supplemental pumping from wells. About 30 to 40 per cent of the areas in the Laguua and Riverdale Irrigation districts were provided with supplies secured by pumping in 1924. Manj' additional plants have been installed since 1924. In the areas on the south side of the river, in the Alta Irrigation District nearly all of the 81,500 acres irrigated receives both canal and pump supplies. In the canal areas in Kings County little pumping has been practiced until recently; 75 plants were reported in 1925 in the Last Chajice Canal area and 23 in the Lemoore Irrigation District. In the lower areas, along the northerly channels of Kings River, pumping by canal organizations as well as by individuals is practiced. The Stinson and James Irrigation districts secure part of their supply by pumping from wells into their canals. To the south, there has been a rapid increase in pumping from deep wells in the northern part of Tulare Lake. A good indication of the increase in pumping in the upper part of the Kings River area is furnished by the records of the San Joaquin Light and Power Corporation for its Dinuba, Selma and Fresno dis- tribution districts wdiich correspond approximately with the areas of the Alta, Consolidated and Fresno Irrigation districts. These rec- ords are summarized in Fig. 1 which shows the inimber of consumers of agricultural power and the power used by years. Development in the Alta District began somewhat earlier than that in the other two areas; pumping in the Consolidated District or Selma area although beginning later has increased more rapidly. Fig. 1 shows a larger proportional increase in power consumption in 1924 than in th'e num- ber of consumers. This reflects the unusually long period of pumping in 1924 due to the small flow in Kings River. In 1925 the increase in number of consumers was sufficient to maintain nearly as large a power consumption as in 1924 although the canal supply Avas much greater. 40 Departnicvl of Piihlic WorA'.s. Increases in the imniber of consumers in 1926 are reported to be larger than in the preceding years. Tliese figures apply only to the consumers served by this company and do not include plants using other forms of power. It is difficult to estimate the present draft on the ground water in the Kings River areas due to its variation from year to year. For the entire area there is probably a present gross draft of about 500.000 acre-feet per year. This is equivalent to nearly 30 per cent of the mean annual run-off of Kings River. The net draft on the ground water is less tlian this as some of the water pumped returns to the groujid Avater by percolation from the areas irrigated. The availability of ground Avater in this area prevented serious crop injury in 1924 Avh(^n the i-un-off of Kings River Avas the ininimum that has been recorded. The ground water ])asiiis underlying this area thus serve as an excellent storage reservoir that fills during times of excess run-off and may be drawn upon heavily in times of shortage in surface supply. This condition is of very great value to the Kings River area and is largely responsible for the high characti^r of the present irrigation development in ranch of the area. METHODS OF ANALYSIS OF GROUND WATER CONDITIONS. The conditions of canal and ground watei- use vary so widely in the (liflFerenf parts of the Kings Rivei- area that details must be discussed by S(M'tio7is. B(M'ause the replenishmeiit to the ground water supplies comes largely from percolation from the canals and irrigated lands, the areas covered by the large canal systems represent fairly distinct ground Avater areas and th.> conditions of supply and use can be best discussed for the area covei-ed by each of such large s.ysteras. For the smaller systems intermingling of ground Avater requires discussion by groups. The general method of .studying the ground Avater conditions in these areas has been the same. This consists in general in a compari- son of the volume of ground water supply against the volume of its use Avith the resulting effect on the elevation of the ground Avater table. The most important element of ground water supply is the diversions from Kings River bj-rmght into the area by canals. Losses to the ground Avater occur both by seepage from the distribution canals and by ]>ercolation from th(» lands in-igated. Additional supplies may come by ground Avater movement into the area from higher hmds. The use of the ground Avater supply is measured l)y the draft by pumping from Avells. The ground Avater may be depleted also by underground flow toAvard loAver areas or drainage channels. The balance between the elements of supply and depletion Avill be reflected in the fluctuations in elevation of the ground Avater plane. When the elements of supply exceed the elements of use or depletion an accumulation of ground Avater Avill occur Avith a rise in the elevation of the Avater table. When the depletion exceeds the supply a loAvering Avill result. Therefore the fluctuations record the balance betA\een the supply and depletion. From these data conclusions can be reached as to the extent of draft that can be supporfpd by the ground Avater supply Avithout a continued or permanent lowering of the ground water table. Ground Water Rcsunrccs, Southrrn San Joaquin Valley. 41 The use of ground wdtvv j-ecjuircs fiuetuations in its elevation. A ground Avater supply represents a form of storage which must be accumulated in the soil at times of surplus so as to be available for use in times of need. Fluctuations in the elevation of the ground Avater are a normal process. A regular range of iiuetuation indicates a definite source of supplj'. Several feet of lowering within a season does not necessarily indicate overdraft. Tf. however, at similai- periods during the season the ground water is progres.sively lower from year to year under conditions of average supply, draft in exces.s of the supply would be indicated. The ground water elevation at the same time in different years when compared to the conditions of supply and use for tlie same years furnishes a basis for estimating tlie draft which can be supported by the average supply. The water delivered into a given area and the acreage of crops irrigated were obtained from the records of the canal systems for the years covered by the ground water records. The fluctuations of the ground water were obtained from the readings of the observation wells. Any ground water movement into or out of the area is relatively constant unless a wide fluctuation in the ground water elevation occurs. For several of the areas, ground water records for the years 1922 to date are available. This period includes the very dry season of 1924, the somewhat above normal season of 1922 and the somewhat below normal years of 1923 and 1925. These seasons give a relatively wide range of conditions of canal supply and ground water use. The analysis presented for tbe different areas represents directly only the ••onditions din-ing the i)a)-tiL'ubii' years of actual record. Should chaniies in tlie conditions occur in tlie future the resulting conclusions mav require similar modification. The fluctuation records of tbe observation wells show certain com- mon characteristics. The ground water rises during the period of canal supply ; it falls during the late summer months when canal supply is small and pumping heavy. Tn the fall when pumping becomes rela- tively small in amount, the rate of ground water lowering decreases. The water table may either lower or rise during the winter months dependent on local conditions uf ground water movement and use. In examining the ground water fluctuations it was found that Decem- ber 1 represented the end of the period of use by pumping and the beginning of th(» winter sea? on. Tn many areas the ground water starts to rise at about this date. These conditions continue until about March 1 of the following year when the decrease in rainfall and the increase in use results usually in a lowering of the ground water unless water is being delivered in the canals. For these reasons the year has been divided into two parts in the study of those areas for which com- plete records are availa])le — the season of canal diversions and pump- ing for irrigation extending from March 1 to December. 1.; and ihe winter season from Decem])er 1 to March 1. ':':. ' :.. For the winter season the ground water fluctuations were found to have no consistent relationship to the amount of the canal diversion during the preceding season. The amount of the diversions during the summer affects the fluctuations during that period but has little effect on the fluctuations during the following winter. It was found that the winter fluctuations vary, usually consistently, with the amount of 42 Department of Public Works. rainfall during the winter months. This relationship is considered to be indirect, as direct penetration of moisture from the rainfall to the ground Avater probal)ly does not occur except perhaps to a limited extent at times of heavy precipitation in areas where the ground Avater is within a few feet of the ground surface. Other factors such as winter pumping and local run-off vary Avith the rainfall. In Avinters of small precipitation some pumping is practiced. In years of large rainfall such pumping is reduced and any locally tributary run-off is increased. The net effect of all factors results in the ground Avater fluctuating in proportion to the rainfall during these three winter months. For i)uri)0ses of discussion the Kings River area has been divided into several separate areas representing differences in conditions of canal diversion, extent of pumping or length of period covered by the ground Avater records. The available information regarding each area is presented Avith such tentative conclusions as the available data appears to Avarrant. It is considered that the available data furnished ade- quate support for the general conclusions presented. Additional records in the coming years Avill probably result in some modification of any detail numerical conclusions that might be reached at this time regard- ing the draft that can be supported in any area. GROUND WATER IN THE FRESNO IRRIGATION DISTRICT. This district includes an area of 240,664 acres, of AA'hich 163,377 acres are reported as served by canals and 30,384 acres as served exclusively by pumps. The canals serAdng this area Avere built over 50 years ago. The early priority of its Avater rights enables this dis- trict to secure a more dependable Avater supply than many other areas on Kings River. These conditions make the study of its ground water of particular interest as representing conditions of more complete AA'ater supply. The Fresno Irrigation District is served by two canals. The Fresno Canal served about two-thirds of the total area in the loAver or western part of the district and the Gould and Enterprise canals the higher or eastern portion. The Fresno District began observations on about 100 Avells in September, 1921, mainly under the Fresno Canal, and the Fresno City Water Corporation on about 25 wells, mainly under the Gould Canal, in November, 1923. There are no irrigated- areas above tlie Fresno District, so that it receives no ground Avater supplies from such sources. The locally tributary drainage area has only a limited run-oft', estimated as an average of about 8000 acre-feet per year. Such run-off is very irregular in occurrence and is neglipible in (piantity in years of small rainfall. The amount estimated is only about 2 per cent of the average annual diversion of the Fresno District. Prior to the construction of canals, ground Avater occurred at depths of about 60 feet. As a result of irrigation, the ground A\-ater rose until a considerable area, largely .south of Fresno, became damaged by Avater logging and alkali so that farms formerly productive in Adnes and trees Avere useful only for bermuda or salt grass pasture. Evi- dences of such damage are still observable in this area. Efforts toAvard drainage were made, and investigations and experi- ments conducted by various agencies. These earlier attempts Avere Ground Water Resources, Southern San Joaquin Valley. 43 mainly with opon ditch or tile drains for small areas. No attempt to drain the general area was made, although plans for such works were discussed. In recent years pumping for irrigation has increased throughout the district to such an extent that much drainage has heen provided indirectly. The result has been to control the ground water until at present drainage is not a serious problem in this district. The existing pum])i ng. together with control of the canal diversions, is sufficient to control ground water conditions. Any material rise of the ground water with resulting water logging of land is not to be expected under existing conditions of M-ater supply and a normal increase in irrigated area. Any local area in Avhich such a rise may occur can be controlled by additional local pumping. AVhile ranch of the practice regarding the control of the ground water by pumping will be subject to develop- ment and adjustment in the future, it is considered that existing experience fully justifies the conclusion that pumping can control the ground Avater and tliat the demands of pumping for irrigation will result in such control. Pumping for drainage only is not probable as all water pumped can be coordinated with the irrigation demand resulting in dual usefulness. Pumping for irrigation has been very largely a development of the last ten years as shown in the previous discussion of the growth of pumping. The draft in 1923 appears to have been about three times as large as that in 1913 ; in 1924 the pumping was over twice as large as in 1923, due to the deficiency in canal supply. Most of the increase from 1914 to 1923 appears to have occurred prior to 1920. There may be some question as to whether the present draft has been in effect long enough to result in stabilized ground water conditions particulai'ly in the outlying areas. The conditions for securing M'ater by pumping from wells are par- ticularly favorable in practically all parts of the Fresno District. Dis- charges of from 1 to 2 second-feet can be secured from wells of less than 150 feet depth in the larger part of the area. Wells of greater depth recently installed by the district have produced 4 to 5 second-feet. The drawdowns under such rates of discharge are relatively less than those in areas of closer textured material so that the pumping lifts are relatively small. Bulletin 217 of the Office of Experiment Stations, U. S. Department of Agriculture, described ground water conditions southwest of Fresno. The field work was done mainly from 1904 to 1908. A comparison of the original records of this field work for Avell No. 1 with well No. 16 of the Fresno District shows a generally lower elevation of the ground water in recent years. The results are shown in Fig. 2. Twenty-one wells were observed at the Kearney Vineyard by the College of Agriculture, Universitv of California, during 1914, 1915 and 1916, and for 1920, 1921 and 1922. Tlie average diversions and the rainfall in the earlier years were slightly larger than in the latter three years. The average depth to ground water on October 1 was 5.8 feet for the first three years and 8.0 feet for the latter years. The city of Fresno is excluded from the Fresno Irrigation District although some canals cros.s the city. The Fresno City Water Corpora- tion secures its water supply by pumping from wells within the city, the 44 Department of Puhlic Works. present draft bein^ al)()\it 2().()(){) acre-feet per year. The y:i'()inui water is noAv lowei- than formerly, as discussed hiter in detail. In ,sonie parts of the district Avhere the lands had gone l)ai'k to pastni'aue, due to the rise of the i,^round water, plantings ai'e ho'mg made. The general impi'ession gained from field ol)servation is that the new plantings are encroaching on the area formerly water logged and alkaline rather than the reverse. This also indicates that ground water conditions in such areas are improving. It is not i)()ssible to specify any single item as the cause of tiie general gi'ound watei' changes that may be occurring. Among ]irobable Ground surface a O JAN. FEB. MAR. APR. MAY JUN. JUL. AUG. SEP. OCT. NOV DEC. LEGEND. Well No. 1 of Baker Tract. 1907 — 1M8 vVell No. 16 of Fresno Irngation District. 1921—1926 FIG. 2. Comparison of ground water- levels 1907-1926 in Fresno irrigation District. causes would be more careful use of water on \ho land, a better main- tained canal system, more regular delivery methods and the increase in pumping draft. AVhile all of these factors may affect the result, the increased pumi)ing draft is regarded as the most important single factor. AVhile there may be some doubt regarding the relative effect of these different factors it is considered that the available data fully support the conclusion that groinid water control has been established in this district. A recurrence of an injurious rise of the ground water is not to be expected. Ground Water Kcsonrces, Sauthern San Joaquin Valley. 45 GROUND WATER FLUCTUATIONS FROM DECEMBER 1 TO MARCH 1. The ground water fluctuations from December 1 to March 1 for the entire area under the Fresno Canal are shown in the following table: Average prounil water fluctuation from December 1 ■ Diversion in acre-feet to March 1 in feel Rainfall from per acre of combined ° +— rrise; December 1 to March t canal and pump service Season — :=r.loweriii(/. in inches area 1921-1922 +1.2 8.12 2.02 I!l22-1923 + .2 4.04 1.93 1923-1924 — .(; 1.09 2.12 1924-1925 + .4 3.99 .96 192.S-192B -t.04 ' :!.26 2.4 Canal diversions during the winter months are usually small. In 1924-25 about 35,000 acre-feet were diverted by the Fresno Canal in these months; in the other years shown in the table the diversions were less than 10,000 aere-feet, T\\q mean precipitation at Fresno for these three months is 4.45 inches. In Fig. 3, the ground water fluctuations during these winter months have l)oen plotted against the rainfall for the same months for the sea- sons covered by tlie records. The results are shown for the Fresno and Gould Canal areas as a whole and also for selected smaller areas under the Fresno Canal. In general a consistent relationship is shown. The preceding talile shows that the ground water fluctuations during the winter are not directly related to the amount of diversion during the preceding summer. For all lands under the Fresno Canal the results for the different years fall quite consistently on a straight line relationship. The results for 1924-25 are probably affected by the larger canal diversions during that winter. For the area under the Gould Canal, the ground water records do not include the seasons prior to 1923. A consistent relation- sliip is indicated by the records of the three seasons shown on Fig. 3. For the entire areas under the Fresno and the Gould canals, an aver- age rise of 0.3 and 0.1 feet, respectively, is indicated by Fig. 3 in winters of normal precipitation. In such years the additions to the ground water from the run-off' of adjacent areas and winter canal diversions appear to exceed slightly the pumping during this period and such outward ground water movement into lower areas as may occur. In seasons of large pi-ecipitation some penetration of rainfall within the area to tlie ground water may occur althougli the amount of siK'li penetration witli ))r('S(Mi1 deptlis to ground water is proliably small. For the smaller areas uiuh'r the Fresno Canal differences in the winter fluctuations arc shown in Fig. 3. The Dry Creek Canal serves lands west of Fresno in the lowei' portion of tlu' district. The Fancher (!reek ('anal serves lands south of Fresno. Both areas are distant from any large stream channels having continuous flow. The elements of .sup]il}' appear to exceed tlie elements of use for the Dry Creek Canal area and a small rise in winters of normal rainfall is indicated. For the Fanchei' Creek Canal, tlie elements of supply are sulificiently large to result in a rise in all winters except those of very small rainfall. The Ilerndon Canal serves lands along the San Joacpiin Kiver in the western pai-t of the disti'ict. Tlic gi'ound water slopes awa,y from this 4G Department of Pnhlic Works. DRY CREEK CANAL. ■J c O 4-3.0 +2.0 +1.0 0.0 ^3.0 +2.0 +1.0 0.0 -1.0 0.0 -1.0 -2.0 0.0 -1.0 -2.0 i»^"" -^ 1924-25_. 1922-23 --^ 1923-24 • **" ' 1925-26 • 4 6 FANCHER CREEK CANAL. 4 6 HERNDON CANAL. 2 4 6 8 AREA UNDER FRESNO CANAL. Exclusive of Mil! and Fancher canals. 4 6 8 TOTAL FRESNO CANAL AREA. 4 6 TOTAL GOULD CANAL AREA. +1.0 Rainfall inches. 10 ^^^ ^^^ 1921-22 -1923-24 1925-26 924-25. •1922-2: 10 _f^ iq?4.-;b.l 1 *1921-22 1925-5 ^1922-2; 6 1923-24 10 1925-2 1924-25 •1Q91.99 6j^ J 71922-23 1923-24 10 10 FIG. 3. Relation of change in level of ground water during December, January, and February, to rainfall during the same months, in Fresno Irrigation District. Ground Water Resources, Southern San Joaquin Valley. 47 area on all sides as shown by ^Nlap No. 1. The ground water lowers in all winters the outward -movement even in years of larj^e rainfall appears to exceed tlie elements of supply. The area under the Fresno Canal exclusive of the Mill and Fancher Creek canals consists of an area in the southeastern part of tlie dis- trict below the area under the Gould Canal and adjacent to but above the Consolidated Irrigation District. The ground water has lowered in all winters covered by the records. Outward movement appears to exceed movement into the area from higher lands. GROUND WATER FLUCTUATIONS MARCH 1 TO DECEMBER 1. For the main canal delivery and crop growth season, the ground water fluctuations vary with the extent of the canal supply. The records of the Fresno District include the water delivered to main laterals and the area served, both by canals and by pumping under each lateral. The ground water fluctuations have been averaged for the same areas. Water delivered into any area is used mainly to supply the moisture consumed by the crops and evaporation from the soil within the area. Some outward ground water niovement may occur, also inflow from higher areas may be received. Any difference in the balance of items of supply and items of use will be reflected in the ground water fluctuations. The areas reported as irrigated are the total areas of the farms receiv- ing service ; not all of the area of each farm may be actually cropped. However, the development in this district is relatively intensive and the proportion of unused land on the developed farms is relatively small. There are, however, farms on which no service is received, the lands being undeveloped. These lands are excluded from the crop area. Ground water fluctuations affect the gross area ; crop use applies only to the area actually growing crops. If only a portion of any area was irrigated, the resulting ground water fluctuations from any rate of delivery per acre of crop would be changed. For the six canal areas for which comparisons are presented the areas are as follows : Canal Gross area Herndon r)5,944 Drv Creek 49,988 Mill Creek 110,403 Faiioher Creek 50.120 Kntire Fresno Canal 168,G22 Gould Canal* 73,341 * Includes the Enterprise Canal. The four years covei'cd by the ground water records include 192-1:, in which the canal sui)pl_\- was only aliout one-half normal. The remain- ing three years varied somewhat in the amount of the diversion. Due to the early priority of the rights of this district the diversions vary less widely than the run-off of Kings River. The ground water fluctuations and the average diversion per acre of cropped area are shown for the areas under the Fresno and the' Gouhl canals in the folhnving table. The fluctuations arc for Ihe Area in Acres Area Area Unde- receiving receiving veloped Per cent canal service pump service area developed 41,839 5,713 8,392 85 25,809 4,186 19,993 60 71,009 10,638 28,756 74 37,036 8,794 4,290 85 113,990 21,482 33,150 80 49,387 8,902 15,052 80 48 Department of Fublic Works. HERNDOfJ CANAL. FANCHEH CREEK CANAL. E V o o O ID 2 u c 1_ u *-» ro $ 13 C 3 O > c u a c n .c O H2.0 + 1.0 0.0 -1.0 -2.0 -3.0 -4.0 -5.0 + 1.0 0.0 -1.0 -2.0 -3.0 -4.0 -5.0 -+1.0 0.0 -1.0 -2.0 -3.0 -4.0 -5.0 /•I 923 1922 •/ / 192 / 5 • / 1924 3 4 DRY CREEK- CANAL. 1 192 •1925 2/ > /i92: / / 1924.' f 12 3 4 /IILL CANAL. 1922 /■" J25 y \ / / / i • 1924 +2.0 + 1.0 0.0 -1.0 -2.0 -3.0 -4.0 n^z^ \ f 19227 / / • / 1924 ENTIRE AREA UNDER FRESNO CANAL. +2.0 + 1.0 0.0 -1.0 -2.0 -3.0 -^.0 /l925 1922, /■ / 1923 / / 1924, ' GOULD CANAL. +2.0 + 1.0 0.0 -1.0 -2.0 -3.0 -4.0 1925 / / / J 1 /I /l924 /I FIG. 4. level of District. Canal diversion in acre-feet per acre. Relation of volume of water diverted by canals to change in ground water in areas under canals in Fresno Irrigation Season 1922 1923 1924 Diversion in acre-feet per acre of total crop area 1.93 2.12 .9G i;'2r> 2.3 Diversion in acre-feet per acre of total crop area Averaoe fiiictitation of the (jround water in feet 1.91 1.57 .SI l.'J -t-1.1 Ground V^'ater liesoiirces, Sauthern San Joaquin Valley. 49 period March 1 to December 1 which includes nearly all of the canal diversions and the pumping for irrigation. Fresno Canal Area Gould Canal Area Average fluctuation of the (/round water in feet + 0.15 — 0.15 —3.95 + 1.0 Total for four year period — 2.95 Tile ground water lowering for this four-year period has been less than that in almost any other area in the southern San Joa ear should result in a rise of one foot if the balance for the full year is to be obtained. The combinations of ground water fluctuations for both the winter and sununer periods indicate the following : Estimated acre- feet per acre required to Winter fluctuation inointt'iu around water Canal area in normal years, feet for entire year Herndon : — 4 2.25 Dry Creek -f-l.S 2.15 Mill CveeM. -t-0.3 2.2 Fancher -|-0.4 1.85 Whole Fresno -fO.3 2.0 Could +0.1 1.G5* * Based on 2 years record only. Ground Water Resourccfi, Southern Son Joaquin Valley. 51 For tlu' wliok' vcjir tli«n-«' is less cHrt'oreiK'f between tlie different areas than for the period Mareli 1 to Deeeinher 1 only. The winter rise nnder tlie Dry Creek Canal reduces the delivery required during the reinaindei- oi" the season. For the Ilerndon Canal the lowerinis: of 0.4 feet in the three winter months would be at the rate of 1.6 feet per year. If this lowering is assumed to be due to outward ground water movement, a consuniptive use of only 1.6 acre-feet per acre would be indicated by Fig. i for this area. As this area is largeh' in trees and vines this result is consistent with the results for the Gould Canal. The estimated rates of consumptive use shown in the preceding table are based on the indications of the records of the last four years. During this period a material change has occurred in the extent of pumping and in the depth to ground water over much of the area of the Fresno Irrigation District. The conditions of use of moisture may not have become sufficiently .stabilized nnder these changed conditions for the results based on the records for these years to represent the numerical values for consumptive use that may be found in coming years when conditions may have become less variable. The estimates shown are presented as an illustration of the method of analysis eonsidered applicable in the study of ground water utilization and as an illustration of the apparent consistency of the results secured even in such years of varying conditions as those covered by the records in this area. The consumptive use for any area represents the amount of water per acre of irrigated crops that needs to be brought into the area to supply the moisture actually consumed by such crops. The canal supply may be less than the consumptive use in some years provided excess sui)ply is available in other years to equalize such deficiencies and that ground water storage may nuike the surplus supply of excess years available in years of deficient supply. Any shortage in the average supply l)elow tlie amounts required for consumptive use will residt in a reduced crop production. These requirements for consump- tive use differ from those for ordinary diversion in which only the requirenu'nts of surface application are considered without recovery of lasses to the ground water by jnimping. In such supplies for surface ai)idication alone, the requirement is more usually expressed in terms of tlie maximum diversion in any year. Some shortages in such maxi- mum requirements can occur in occasional years without serious injury. Any shortage in the average supply for the requirements for consumptive use will result in crop injury or in gradual lowering of the ground water if ground water storage is drawn upon to replace .such shortages. *o^ k Drainage Factor. The amount of water nmde available by a lowering of the ground water depends on the proportion of the soil volume that is filled with wafer which is yielded by sudi lowering. This proportion may be termed the drainage factoi-. If is less than the total pore space of the soil material as the entire wafer contained will not be secured by a ground water lowering. The lowering of the ground water that tJimi DapatimenI of Public M^irls. WELL E8. Above Gould CanaL WELL 68. South of Fresno. »1 Tl^ „tm^- WELL 38. Under Gould CanaL WELL 31. West of Fresno. ■J o u WELL 44. Under Gould Canal near San Joaquin River. WELL 87. Southwest part of district. WELL 69. Northeast of Fresno. Q WELL 28. Near Kerman. WELL 85. Southeast of Fresno. WELL 41. Northwest part of dislrid. zaioco:>-2-'Oa-i- >o ->u.5<£-)-><'')02Q LEGEND. 1920 — 1921 -^ 1922 FIG. 5. Hydrographs of typical wells in Fresno Irrigation District. Ground Water Bcsources, Soidlirrn Sun Joaquin Valley. 53 resulted from tlie shoi-tajLic in canal supply furnished a basis for estimating the drainage factor for this area. S"uch estimate is based on the assumption that the defieieney in canal supply in 1024 was leplaced by the water represented by the ground water loweriiig. This assumption gives values of the drainage factor larger than the actual value as some shortage in the moisture secured by the crops occurred in 1924. Foi- the two-year pei-iod covering 1922 and 1923 the ground water in the area under the Fresno Canal remained at the same average elevation. In 1924 the ground water lowei'ed an average of 3.95 feet. The canal diversions in 1922 and 1923 averaged 274,000 acre-feet. Tn 1924 only 130.000 acre-feet were secured. For the gross area under the Fresno Canal of 168.600 acve-feet, if the difference in canal supply of 144,000 acre-feet is considered to be replaced by the drainage of 066.(^00 acre-feet of soil volume, a drainage factor of 22 per cent is indicated. A similar comparison for 1924 and 1925 gave the same ^•alue foi- the drainage factor. Under the Gould Canal the records for 1924 and 1925 gave an indicated value of 20 per cent for the drainage factor. These indicated values of the drainage factor are relatively large. They exceed the probable actual values as some shortage in crop use of moisture occurred in 192-1. Plowever the materials in this area are relatively open as indicated by the usually large discharges with small drawdown that are secured from wells. The indicated value for the area under the Oould Canal is larger relatively than that for the Fresno Canal, as the materials under the Gould Canal are of less open character. Hydrographs of Typical Wells. Hydrographs of typical wells are shown in Fig. 5. AVell 58 is just above the Gould Canal. Tjowering occurs during the summer months with a rise in the winter. Well 38 is about 2 miles southwest of Clovis in the irrigated area ; it rises during the irrigation season and lowers in the winter. Ovei' one-half the lowering in 1924 was recovered in 1925. Well 44 is near the San Joaquin River north of Fresno in an area of limited local irrigation. Less fluctuations with the canal ]utnips arc distributed, and is a much heavier I'ate of ]tuiiipin;j: di'aft than lias heeii found to be supported elsewhere in the valley. It is considered that the conditions are particnlai'ly favorable in Fresno for such pumpincr. The drainage factor is large, indicating open material. Relatively large discharges are secured from relatively shallow wells without excessive drawdown also indicating free move- ment of ground water. Fresno is surrounded by irrigated areas receiving canal service and is crossed by canals supplying some direct see]iage. Noiie of the wells within the city are more than two miles from irrigated areas. These favorable conditions do not occur in some of th(^ other areas having heavy pumping drafts and the results in Fresno are not considered to furnish a criterion by which the results 1o be expected in such other areas can be predicted. GROUND WATER IN THE CONSOLIDATED IRRIGATION DISTRICT. The same cliaracter of records are available and the same method of discussion has been follow^ed for the Consolidated Irrigation District as for the Fresno Irrigation District. The Consolidated District receives water by diversion fi-oin Kings Kiver through its own canals and also through the Lone Tree Canal from the Fresno District. The Consolidated Disti-ici also delivers water to the Island No. 3 District. The canal supply considered in the following discussion is the net supply of the area within the district boundaries. Cround water is readily obtained throughout the district in wells oi' shalloAV depth. As the canal supply is available mainly only during a short season, pumping both as the entire source of supply and to sup])lement canal service has been extensively used. Of the gross area of 149.888 acres in this district, 81,500 acres are re])orted as receiving canal service and 44,000 acres as 1>eing supplied entirely by pumps. The season of delivery under the canals is usually short, the water rigid of this district supplying less water in late sum- mer months than that of the Fresno district. In conseriuerice. nearly all land I'cceiving canal service secures supplemental supplies for puni[)ing. The upper end of the area served by the Consolidated District near SJanger is adjaccTit to the upper end of the Fresno District and Kings l^iver. The district extends to the southwest, being bounded by Kings l\i\-er along the east. As shoAvn on Map No. 1 the ground water in the poftion of the district adjacent to Kings I?iver slopes toward the river, the i-einaindei- has a slope in a general southwesterly direction. The gi'ound water fluctuations vary within the district due to these factors of location. They also vary, depending on the relative areas of canal and pump service. In the western portion of the district there is nearly as large an ai'ea supplied entirely by pumps as there is supplied by canals: in the remainder of the district there is over three times as large an area under canal service as served by pumps alone. Satis- factory supplies can be secured from relatively shallow wells in. all parts of the district. Ground Waicr Ersourcrs, Southern San Joaquin Valley. 57 GROUND WATER FLUCTUATIONS DECEMBER 1 TO MARCH 1. Tlio ground wator rtiu-tuatioiis for tlie ontiro district for each winter for which records are available are shown in the following table: Divprsion in arrc- Average yround water feet per acre of fliiclndtion from Dec. 1 h'nhifnll frcna combined canal and to Mar. 1 of the folloic- Dec. I to Mar. 1, Hca.fon pump service ing ic inter, in feet in inches 1922 2.05 — 0.1 4.04 1923 1.7.T —0.6 1.09 ri24 .20 —0.05 3.99 l;j2r) 1.64 —0.4 3.26 In order to indicate the eflPect of the general ground water conditions on the ground water fluctuations during the winter months, the area of tlie district was divided inlo four parts representing approximately equal areas exi ending across the district from the northeast toward the southwest. These areas do not represent lands served by separate canals, as the distribution system extends in general across their boundaries. Tile ground water fluctuations from December 1 to ^larch 1 for each of tlie.se four areas are shown in Fig. 6. Tlie greater tendency toward lowering in the upper portion of the district and the gain even in years of below normal rainfall in the lower areas are shown by these results. The rainfall for these months at Fresno was used for these comparisons. 'I'he average rainfall is 4.4') inches. The amount of rainfall required to maintain the ground water during these months appears to he as follows : Flucluation s Tnrh.es rainfoll that would- Dercmber 1 to March t occur xcith required to m.ainlnin vormn.l rnin- Arra. fjroiind water '""• Frr.t. 1 (1 — .:? 2 7 — .4 ?, 4 4 2. .5 +.4 AVliole di.strict 4.5 If no rainfall occurred, the ground Avater in areas 1 and 2 would apparently lower an average of about 1.25 feet during the winter months. The lowering under the same conditions in areas 3 and 4 Avould be about 0.5 foot. This lowering Avould be the result of draft and ground water movement. If the draft is assumed to be uniform in both areas a draining out from the upper area of about 0.35 foot depth of ground water during these three months would be indicated. This would be ('(puvalent to a draininu' out of 1.4 feet depth of ground Avater ])er year or about one-third acre-foot of Avater -per acre. The (hflference in the fluctuations in the.se areas indicates that some ontAvard movement of gi'ound water occurs from the higher to the lower areas. GROUND WATER FLUCTUATIONS MARCH 1 TO DECEMBER 1. The average ground water fluctuations for the entire area of the Consolidated District together Avitli the diversions are sliOAvn in the folloAving table for the years covered by the available record. The k 58 Department of Puhlic Works. ground water fluctuations are those from March 1 to December 1. The canal delivery is also received during this period : Season 1922 _ 1923 _ 1924 _ 1925 _ nit-e^rsion in ncre-feet per acre of total crop area 2.05 1.75 0.20 1.64 Avr.ruae fluctuation of the (/round water in feet + 0.45 — 0.15 — 3.15 + 0.55 Total for four-year period — 2.30 -1-1.0 -2.0 AREA 1. AREA 4 -(■1.0 -1.0 o ai 0.0 -1.0 AREA 2. ^•iq? 1924-25* |.?4 ''' •1922-23 ^5-26 ■n.o ENTIRE DISTRICT. Ol c JZ a u > < ■n.o -1.0 AREA 3. Areas 1,2,3 and 4 extend across the district in a southeasterly and north westerly direction from Northeast to Southwest. Rainfall in inches. FIG. 6. Relation of change in level of ground water during December, January, and February, to the rainfall during the same months, in the Consolidated Irrigation District. The available canal delivery records enable the ground water fluctua- tions and delivery of water to be compared for three areas in the district. One area consists of lands in the upper portion of the district, Ground Woier h'csouncs. Southern San Joaquin Valley. 59 one of a larger area in the soutlieastern part of the district extending along Kings River and the third is the western half of the district. The groiuul water Huctuations fi'oiu ^Nlarch 1 to Ueceiiiher 1 are I>lotted against the delivery of water per acre of total crop served l)y both canals and i)unips in Fig. 7 for each of the four years covered by tlie records. These comparisons are made on a similar basis to • those previously discussed for certain areas in the Fresno District. In general a fair consistency is sliown between the (piantity of water delivered per acre of crop and the resulting ground water fluctuations. E u o I) Q u rs E 8 UPPER END OF DISTRICT. +2.0 +1.0 -1.0 -2.0 -3.0 / 192 5» /• /i9; 1922 13 / / J 24 1.0 2.0 3.0 4.0 SOUTHEAST PART OF DISTRICT. +2.0 + 1.0 -1.0 -2.0 -3.0 -4.0 /.1 922 192*5 J A 1923 1 / /l92 4 1.0 2.0 3.0 4.0 3 ? at o SOUTHWEST PART OF DISTRICT ? Under Fowler Switch Canal. c o a c ^^iJ -ri922 a 1923/ J -1.0 ~7 -2.0 / / -3.0 /l92^ ENTIRE DISTRICT. +1.0 -1.0 -2.0 -3.0 -4.0 1 )25«y 1 •1922 /19 23 / ' / ^1924 1.0 2.0 3.0 4.0 1.0 2.0 3.0 4.0 Canal diversion in acre-feet per acre. FIG. 7. Relation of volume of water diverted by canals to change in level of ground water, in areas under canals, in Consolidated Irrigation District. The results for 1925 are less consistent with those for 1922 and 1923. In 1925 the general gi-ound water was lower and losses by outward movement and from low areas usually wet were reduced. For the upper area, in order to maintain the ground water, a delivery of about 2.25 acre-feet per acre appears to be required. For the area along the river with higher ground water as in 1922 and 15)23, a requirement of slightly over 2 acre-feet per acre is indicated ; for the conditions in 1925 less than 2 acre-feet appears to be needed. For (iO Df'parlmrnI of Puhlic Vi'orks. WELL 7. Npar Kinns River. WELL 18. Near Fowler. WELL 25. West of Selma. WELL 20. East cl Selma. WELL 13. NortlTwest part of district. WELL 42. Near Kingsburg. Z[DCCCt>z-'Ca->->o 2^5 < S^--*- "O i.Q WELL 3?. Southwest part ot district. .< UJ < 0. 2 O- 3 D. Ul O O UJ -> u? 2 < y> o 2 o LEGEND. 1922 .-- ---.— -^ 1924 1923 *■ •- 1925 1926 FIG. 8. Hydrographs of typical wells in Consolidated Irrigation District. Ground Walcr Ecsourccs, ISoutheni ISan Joaquin Valley. 61 iiverage conditions liable to occur in the future 2 acre-feet would appear probable. For the western part of the district a delivery into the area of 1.4 acre-feet per acre would appear to be sufficient to maintain the ground water. Tlu'se indications vary rather widely. The variations are relatively consistent, however, when the local conditions are considered. Outward i!!OV(Miient Avould be expected to occur from tiie two upper areas Avhich would increase the delivery rcfiuired to maintain the s:round water. Such movement into the lower area api)arently occui-s. For the whole district the average requirement for delivery into the district appears to be about 1.75 acre-feet per acre of area irrigated. The difference in the indicated rfquirement for the upper and lower area would eorre- sr)ond to a grouiul water movement into the lower and western ai'ea of about 0.33 acre-foot per acre which is in agreement with the indicated movement based on the fluctuations during the winter months. The variations in evaporation from moist areas and reduction in out- ward movement due to the lowering of the ground water during the period covered by the ground water records prevent the making of an estimate of the drainage factor on the basis used in the Fresno Irri- gation District. The probable drainage factor for llie Consolidated District area would be expected to be as large as that for the Fresno District, as the soil materials are fully as coarse in texture. If a value of the drainage factor of 20 per cent is assumed, for 1922 liie total canal supply received in the Consolidated District minus the water represented by the rise of the ground water would be about 24-r),U00 acre-feet Similarly for 1925 the total canal supply received in the distri(?t minus the water represented by the ground water rise would be about 190,000 acre-feet. If the same area of crop consumed the same amount of actual moisture in these two years, the indicated difference in outward movement of ground water and loss of mois- ture by evaporation from ponds and moist areas would be 55,000 acre feet. This would represent a reduction in ground water losses due to the lowering of the ground water between 1922 and 1925. Additional I'criods of record should be secured before dependence should be placed in the amount of this indicated dift'erence. These results however are sufficient to indicate that a smaller canal supply will meet the crop requii'ements and nuiintain the ground water under the ground water conditions obtaining in 1925 than would be required under the con- ditions of 1922. Hydrographs of Typical Wells. lI\drographs of typical wells are shown in Fig 8. Well 7 is near Kings River south of Sanger; a ra])id rise during the period of canal delivery and a similarly rapid lowering beginning in August is shown. l*art of the lowering in 1924 was recovered in 1925. AVell 20 is 4 miles e^ist of Selma and about the same distance from King.s Kiver. Little recovery in 1925 is shown. Well 42 is near Kingsburg and Kings River; some recovery in 1925 occurred. Well 18 near Fowler shows little effect of canal service and a small lowering in 1924. Well 25, 2 miles west of Selma, shows the cft'ect of use in tlie canals with a lowering in 1924 that was not recovered ill 1925. Well ];? in the northwest corner of the district shows little ()2 Department of Public Works. iiioiitlily fluctiKitioii mid little lowcriiiu' occuri'cd cxeopt in lf)24. Well :}8 ill the southwest part of the distriet siiows the ett'eet of the pumping in that area. Lowering has occurred in each year since 1923. GROUND WATER IN LAGUNA IRRIGATION DISTRICT. The pumping plants in the Laguna Irrigation District were can- vassed hy the district during the winter of 1924-25. A total of 108 plants were reported, of which nearly one-half had been installed in 192-1. Open bottom, well point and perforated wells are used, about two-thirds of the plants being well points with from one to three wells per plant. All wells reported are relatively shallow, many not exceed- ing oO feet in depth. No deep or artesian wells are reported and the conditions for obtaining such Avells are not known. Judged by condi- tions to the west in the Riverdale District and the results with wells near Conejo to the east, wells of good yield, 600 to 800 feet deep, should be obtainable in the Laguna Distriet. The depth to water in 1924 varied from 6 to 15 feet ; the conditions in 1924 i-esulted in a lower ground water than normal. Drawdown wlien operating averaged about 20 feet. The average discharge is about 0.8 second-feet. The plants installed at the time of this canvas.s had sufficient capacity to irrigate alwut 30 per cent of the area in the district. A material increase in the number of plants has occurred since 1924. Ground water records were begun in this area in August, 1925. The records now available are not sutticient to permit a detail analysis of the ground water supply to be made. Available data support the con- clusion that relatively inexpensive plants can be installed in this dis- triet. which can be (\\pected to give discharges of al)out one second-foot with relatively small lifts. Under existing conditions of canal supply which result in a short season of delivery, such pumping plants should assist in controlling the uround water so that it does not rise to such iieiglits as to become injurious as well as to sui)ply supplemental irrigation. GROUND WATER IN RIVERDALE IRRIGATION DISTRICT. The records available for the Riverdale Irrigation District consist of a single series of measurements in 1921 and in 1924. ami continuous readings begun in 1925. A comparison of 17 wells observed both in 1921 and in 1924 shows an average lowering of 6 feet. In 1921 thirty-three wells were reported. In 1924 three times this number were iii use. A large part of the increase occurred in 1924. The shallow wells ari- either of open bottom, well point or perforated type. The average dei>th to water was 13 feet with an average draw- down of 21 feet. The average discharge was one second-foot. The depth of open bottom wells varied from 100 to 200 feet, being greater in the eastern part of the district. Well i)oint wells varied from 40 to 150 feet in deptli. those in the eastern part of the area are of less depth than those in the western part. The perforated wells are gen- erally from 80 to 140 feet in depth. Ground Water Resources, Southern San Joaquin Valley. 63 In addition to tlie shalloAv wells, 7 deep or arteoiaii wulls were reported. Tlieso are from SOO to looO feet deep and have an average discharge of over 2 second-feet. Tliere were snflfieient punipinu' i)lants in this distiiet in 1f)24 to sup|)ly about 40 per cent of the area of the district. Tiiero has been a materia! increase in the use of s>'ronnd water since 1924. The extent of di'Vt'lopinent of shidi(»\\- wclis is suftifient to demonstrate the feasi- bility of securing' i>rountl water supplies from relatively inex})ensive plants in practically any ])art of the district. The presence of deeper strata in the western portion of the district is also demonstrated. While no deeper wells were reported in the eastern portion of the district, it is probable that such wells could be secured in this area also. With less expensive shallow sH]ii)]ii's available the desirability of attempting' to secure deeper wells may l)e (luestionable. The Riverdale District receives its main canal supply during a rela- tively short season, t'se is heavy during such periods with a resulting ri.se of the ground water. Pumping from shallow wells is beneficial both from the usefulness of the water pumped and also because of the resulting lowering of the ground water and drainage. GROUND WATER SUPPLIES IN KINGS RIVER AREAS NOT DIRECTLY SERVED BY CANALS. There is an area of about 180.000 acres lying lietween the Fresno and Consolidated Irrigation districts and the areas irrigated by diver- sion from Murphy and Fresno sloughs that is not irrigated. In the past the ground water has been at or near the surface in much of this area. The ground water slopes from the Fresno and Consolidated (bstricts into this area. Surface overflow or ground water movement has resulted in the rise of the ground water to within a few feet of the ground surface. ^luch of the land is now alkaline. Definite infor- mation regarding its original condition is not available but nnich of it appears to have been of jioor quality prior to irrigation. This area has been regarded as a source of ground water supply and some development has been made by the James Irrigation District. All extensive developments planned in this area contemplate the con- veyance of the water secured to otlier areas for use. There are some areas now securing water by pumping for use on the overlying land, but these are relatively small in extent and adjacent to the boundaries of the canal irrigated areas. It has l)een generally assumed that where the ground water was within 6 to 8 feet of tiie surface loss from the ground water would occur due to capillary rise of moisture ^\ithin the root zone of plants or by evaporation fi-om the soil surface. Available inf(u-nuition indi- cates that formerly nuich of this area had ground water within less than (j feet of the surface and there are accounts of difficulties with miring teams and otliei' incidents tliat indicate that water practically .<-;tood on the surface at times. Old roads were built on fills to avoid such dil'ti(;ulties. Actual records of ground water in this area are not extensive. How- ever no records indicate ground water in much of this area within 6 (i4 Department of I'ublic IVor/.-.?. WELLS IN FRESNO IRRIGATION DISTRICT. +4.0 WELLS ALONG McMULLIN GRADE. Not pumped. T3 C o c +4.0 +2.0 ID O 0.0 -2.0 -4.0 -6.0 -8.0 -10.0 1921 PL'MPED WELLS OF lAMES IRRIGATION DISTRICT. 1922 1923 1924 1925 FIG. 9. Change In level of ground water, since November, 1921, In shallow wells of James Irrigation District and wells in adjacent areas in the Fresno Irrigation District. Grounfl M'atcr h'rsources, SoiiHicrn San Joaquiu Valley. 65 feet of the surface in reeent years. AVIumi the wells nf the James Dis- trict were drilled in the northern |>art of this area in lf*2(>. the averaije (lei)th of {ground wafer in the wells was nine feet. This was prior to any draft in this aif.i and followinu' a period of average stream flow. This raises the (piestion of what was tlie source of the water that for- merly reached this ai'ea in sufficient quantity to cause water-logging and now has diminished so that lowering occurred without any local draft. li-rigation in the Fresno ;ii'ea hci^an ahout fifty years ago and increased gradually for man\- years. A^'ailable infornuition indicates that some surface waste probably occurred in these earlier years although no records of its amounts are available. In more recent years the increase in the area irrigated and the closer management of the canals has i-esulted in the reduction and practical elimination of such waste. Also in recent years pumping within the upper irrigation districts has increased rapidly. Such pumping would tend to intercept move- numt of ground water into this area. It is considered that the factors affecting the ground water prior to 1920 would be nuiinly the reduction in surface waste as pumping pi'ior to that time was not as extensive as at present. If this eonclusion is correct, ground water movement into this area was not sufficient Uy itself to maintain the ground water at or near the ground surface. '1 here is an additional ai'ca of similar general character in the south- ern pai't of tliis area between Kings River and Murphy Slough on the south and the Consolidated Irrigation District to the north in which some canal diversions occur. The direct diversions into this area make it difficult to segregate the effect of decreased diversions during recent years of below normal stream fiow and any effects of changed ground water conditions to the northeast. The James Irrigation District has two lines of wells operating in this area. One extends mainly in a north and south line into the area south- west of Kerman, the other extends along McIMullin grade to Dubois. The wells vary from 150 to 300 feet in depth. The average discharge is about 2' second-feet jier well. The total annual draft on these wells has varied from 6700 acre-feet in 1921 to 20.000 acre-feet in 1924. No other adjacent wells were observed prior to 1925. The James District wells lia\'e been I'cad wiicn not operating during the winter season. Some lowei'ing has resulted. There was an average lowering for tlie four years J 922 to 1925 of about 8 feet in the 17 wells extending to the north, of about 4.5 feet in the 14 wells along the ^IcMullin Grade which were pumped and 1.5 feet for the 10 wells which were not ])Umped prior- to 1926. In Fig. it is shown a comparison of the fluctuations of these wells with wells in adjacent areas in the Fresno District, the dates used being those <'orrespon(ling to the dates for which readings on the James wells are available. The grouj) of Fresno District wells, near Dubois, repre- sents the area neai'est to tiie .lames wells, the other is in line with the gi-ound water slope to the east and nearer Fresno. All wells rose dur- ing the winter of 1921-22. Over 8 inches of rain occurred in December, January and February, of this season. The James wells lowered more 5 — I707G 66 Deparfninit of Public Works. during; ]J)22 and 1!)28 than tho wells in the Fresno District. In 1924 the wells in tiie Fresno Uistriet lowei-ed inoie than those of the James Distriet. In 1!*25 the wells of the Fr(»snn District rose, those of the ■James District loweretl. Of the James District wells, those not nsed lowered less than those from which i)uinpinji- occurred. The comparisons shown in Fig. 9 are considered to indicate that there is little direct response in the James wells to ground water fluctuations in the Fresno District. The James welLs, near Dubois, being closer to the Fresno District and not pumped would be expected to reflect fluctuations in the Fresno District more definitely than the pumped wells of the James District. P]xcept for 1922 which wa.s eft'ected by the heavy rainfall of the preceding winter, the unpumped James wells have lowered with little variation due to seasons or fluctuations in the Fresno District. The pumped wells have also lowered continuously at an increasing rate during the past three years. The increased rate of lowering is probably due to the increased pumping from these wells rather than any effect of conditions in dis- tant areas. Observations are not available on which to base an estimate of the area affected by the James wells. The wells are located so that they would be expected to intercept the ground water movement into an area of about 40,000 acres. The total draft for the four years, 1922 to 1925. has been 61.400 acre-feet, or at an average rate of about one and one- half acre-foot per acre, if the area affected is 40.000 acres. The total lowering at the wells has averaged about 5^ feet for the same period. The average lowering over the whole area would be less than this amount. This draft is larger than would be made available from the lowering within this area and some ground water movement into the area is indicated. There is no other extensive development in this area at present. Pumping is contemplated in the southern portion of the area near .^^ur})hy Slough. Test wells about 500 feet deep operated during part of 1926 showed discharges as large as 5 second-feet. It is planned to use the water so developed in an exchange of water between the Foothill Irrigation District and the Alurphy S^lough Association. GROUND WATER IN FOOTHILL IRRIGATION DISTRICT. About 20,000 acres of llu' 56.000 acres in this district are now sup- plieil by local wells within the area. The discharge averages less than one-fourth second-foot per well and the water table has lowered materially in recent years. No sy.stenuitic records of ground water fluctuations have been maintained, but both general observations and the opinions of land owners support the conclusion that the local sources of ground watei' supply are inadequate to support the existing draft. The present planted area consists of about one-half vines and one- half trees, citrus representing nearly three-fourths of the latter plant- ings. Tile water requirements are less than for other types of crops. The wells are generally from 75 to 200 feet in depth to the under- lying rock. The lift has varied from about 12 to 14 feet before pump- ing to a present average of SO to 90 feet. I (jlrouiul l\(;/(7' h'csoiiices, ^ioiillnni Sail .Imuniin Valley. 67 The plottiiifi: of llir depths to water reported in 11)25 on the topo- •rra])lii»' maps of tliis area indicates that the present oronnd water is iclativcly liat having' iitth- shi|)e eitlier toward llie liills or towartl the Alta ("anal on the west. The ireneral jrronnd water elevations appear to he alxmt 2') feet lower lliaii those to llie west of. lint adjacent to. the Alta Canal. It is generally conceded that i)resent development exceeds the ground water supply and that outside sources of supply must be obtained if the existing area is to be permanently maintained. GROUND WATER IN THE ALTA IRRIGATION DISTRICT. The Alta Irrigation District includes 129,o00 acres of which 81,600 acres are reported as irrigated from the canals. While the larger part of the cropped area also secures supplemental water by pumping from wells, a relatively small area de])ends entirely on pumping. Some delivery of water from canals is also made to areas of pasturage in the southwestern part of the district. The water rights of the Alta Iri'igation District result in the district receiving its main water supply in the early summer months. No supply Ls usually i-eceived tluring Augu.st and September, a secondary supply is secured in OctolxM- and November. 'i'he main area of the Alta District is highly developed, principally in \'ines and trees. The southwestern portion of the district is used more largely for pasturage. Ground water supplies for pumping are available throughout the district at relatively shallow depths as shown on ^lap No. 2. Adeijuate yields are obtainable from shallow^ wells. The ground water conditions in the- diflferent parts of the district vary. The ground water and canal delivery records have been sepa- rated for six different areas. The areas along Kings River represent the parts of the district within two to four miles of Kings River, whose ground water drains more directly toward Kings River, as shown on ^lap No. 1 . The area north of Dinuba represents lands between the Kings River area and Smith IMountain. The central area consists of lands, Hiainly south of Dinuba, in the center of the district. The southeastern area consists of lands under several latei'al canals lying east of Dinuba. The Button and Travel- areas consist of the lands served by the dis- trict's canals of these names. The same general method of ground water discussion has been fol- I(er acre of Hnftnntwn from Dei-. 1 I'ti.iiit'ill tnnii combined canal and to .]far. I ut the /o^ok;- r)e<:. 1 to Mar. Season punip service infi winter, in }eet 1, in inches 1''21 1.S7 +0.45 8.12 1hich only 3 feet were recovered in 1925. Tender the lower ground water of 1924—25 and 1925-26 a much smaller rainfall will apparently maintain the ground water in this area during these months than that needed for the conditions of the preceding years. The lower ground water elevation results in a snudlei- grouiul water slope toward Kings Kiver with apparently a rcductinn in the rate of outward movement of ground water. The area noi'th of Dinuba shows similar characteristics to the Kings l^iver area. The total ground water lowering in 1924 was about 15 feet, of which al)out .S feet was recovered in 1925. The Central area gives results which are consisteut for all years. The total lowering in 1924 was about 6 feet, of which about 1 foot was recovered in 1925. The change in ground water elevati *-* ra s ■o c 3 o ^ ^'1925-26 i3-24 2 4 6 8 1 CENTRAL AREA. +2.0 + 1.0 o 1921-22 »" 0.0 > S 19' !4-25 , *1922 23 -1.0 c A /19 23-24 !5-26 -2.0 a c 8 10 AREA NORTH OF DirJUBA. 1925 -26 • 1921-22 ^ 23-24 1922-23 8 10 ENTIRE DISTRICT. +2.0 +1.0 0.0 -1.0 -2.0 192 4-25 • li 21-22 - 1925 y -26y- ^22- 23 /s 23-24 2 4 inches. 8 10 FIG. 10. Relation of change in level of ground water during December, January, and February, to the rainfall during the same months, in the Alta Irrigation District. are fairly consistent. The same areas are used as for tlie winter fluctuations. The ground water lowering in the entire Alta District in 1924 was larger than that in Ihe Fresno or ('i,'ns()lidated districts. The average tH'li\-ery per acre required 1o maintain the ground water is not mate- 70 I)i ixnhiinil of Public Worls. lially (liffcn-f'iit liowevt'i*. 'riic i'ollowinu- table gives the estimated .supply iv(|uire(l for each of tluse ai-i^as to meet crop ncM^ds and maintain the jm'ouikI watei- under cxistinir crop conditions. Tlie results are based on the relationships shown in Fig. 11. ENTIRE DISTRICT. CENTRAL AREA. AREA ALONG KINGS RIVER. u .a E V u V O +4.0 +2.0 -2.0 -4.0 -6.0 -8.0 -10.0 / 1925* / 11923 / '1922 / / / / 1924 + 4.0 +2.0 -2.0 -4.0 -6.0 -8.0 I 1p25« 1 " / f 1923/ / • 1922 J / A / 1924 1.0 2.0 3.0 4.0 +4.0 +2.0 -2.0 -4.0 -6.0 -8.0 -10.0 1923* / 1925* / / 1*922 / / / / / / 1924 1.0 2.0 3.0 4.0 1.0 2.0 3.0 4.0 o ig E 8 3 O V ai c q c O AREA NORTH OF DINUBA. +4.0 +2.0 -2.0 -4.0 -6.0 -8.0 -10.0 -12.0 -14.0 -16.0 1925 / .1923 'l922 / / / / / / / / 1924 +2.0 -2.0 -4.0 -6.0 BUTTON CANAL AREA. -2.0 -4.0 -6.0 1.0 2 in 'S 2"V f 7 1922 1924 TRAVER CANAL AREA. 1923 1925 ■ • 1922. ^ ^ 1924 SOUTHEASTERN AREA. 1.0 2.0 3.0 4.0 1.0 2.0 3.0 4.0 5.0 1.0 2.C Acre feet per FIG. 11. Relation of volume of water applied in irrigation to change in level of ground water during the period March 1 to December 1, in areas in Alta Irrigation District. Kn\)i)lii required lo iiKiivlain fjround water March 1 to December 1, Area acre-feet per acre Along KInKS River 1.9 North of Dinuba 1.8 Central 1.8 Southeastern 1.4 P.utton Canal 1.1 'I'raver Canal 3.5 Entire di.striet l.y Estimated Nit})i)l!j required to uiaintain f/rouJtd water for entire year, acre-feet per acre 2.25 1.9 1.75 1.4 .9 3.4 1.95 Ground ^Vaicr h'rsnurccs. Southern Suu Joatjuin Vallej/. 71 As llic t'r()[)s in tlir Alt;i Dislrict nw iiuiiiily 1 i-ccs and vines, liic con- suMiptive nso of inoistuiH' wonUl he expci-tod to be similar to that found for areas of these ero{)s in the PVesno District, except as the require- ment of any area may l)e affected by ground water movement. Tlie Centra! area is pi-obably moi'e lu^arly free from the intiuence of eitlier irround water inflow or outflow than an.v other i)art of the Alta Dis- trict, inflow apparently sliuiitlx- exceeding' outflow with a probable approximate balance. Tiie larger re(|uirement along Kings River is considered to be due to outward gi'ound water drainage. AVhile the •sandier soils in this area residt in larger ai>plications of irrigation, such larger use wouhl result in a rise of the watei' table were it not for sucli outward drainage. Sonu' outward movement apparently occurs from the area north of Dinuba. Little supply is to be expected in this area from the run-off of the adjacent hill areas, as this is probably intercepted by ])umping on higher lands in the Foothill District. The indicated requirement for the southeastern area is less than would be expected. There is some uncertainty regarding the division of use under the East P>ranch Canal as between the areas north of Dinuba and this area that may effect this result. Less loweriiig occurred in the southeastern area in 1924 than north of Dinuba. Sand Creek passes through this area and some ground water suppl\- From above may be received. For both the Button and Traver canals the coiulitions are not similai* to those for the other areas in that only about 20 ])er cent of the gross area is actually irrigated, although some water may be delivered to additional land for stock watering or occasional pasture irrigation. The figures given appl.y only to the present character and extent of use. Th(> Button Canal sei'ves a long strip of land along the south boundaiy of the district nortli of Cottonwood Creek. About r)()()0 acres out of a gross area of 28,500 acres are classified as irrigated. A delivery of about one acre-foot per acre ])lus inflow of ground water aj^pears sufficient to maintain the ground water under existing conditions. For the present area irrigated this would indicate a ground water inflow of only 8000 to 4000 acre-feet. For the irrigation of additional lands under this canal, a supply at a i-afe similar to that indicated for other areas would be expected. For the Traver canal 5150 acres are reported irrigated in a gross area of 10,600 acres. The irriuated land is located mainly at the north end of the area. All water delivered has been assumed to be delivered to this irrigated area although some delivei-y for pasturage use is made to the remaining lands. In the past high ground water conditions in the lower i)art of this ai'ca have resulted in 1he loss of moisture by evai)oi'ation. The deductions for this area ar(> o)dy ai^piicable under the existing conditions. The amount of water represented by a Huctuation of ground water can l)e estimated from the available records. If the change in the ground water level in 1!)24 aiul 1925 is assumed to represent a volume of water equal to the diffei-enc(> in canal supj)ly in these two years, a draiiuige factor of about 10 per cent is indicated for the upper hard- pan lands and 20 per cent for the lower areas. As some shortage in use by the crops occurred in 192-1, these indicated values probably exceed the actual draiiuige factoi-. The average di-ainage factor for the 72 Departinciil of Public Works. WELL 1. Centerville Bottoms. WELL 93. Near Dinuba. 10 ^ \ ■ 1 ! ♦-♦ 192 LI 9 ^ ^ ^ 1,, i o 6i a Q WELL 150. In Button Canal area. WELL 26. Norlli ol Dinuba zmccK >-z-ioi-t->o "-2<5->-'<<«OZQ 2(ri[r(t>-z-'Oi>-i->o u.5< 54-'«ti'50zO 1921--0. 1922 --I- LEGEND. -o — 1923 — .. -^ _ ; 924 — A- 1925 ♦• FIG. 12. Hydrographs of typical wells in Alta Irrigation District. Ground Wafer J\(s<)iircrs, Souflirrii Son Joaquin VnJliif. 73 cntiit' district is prohiililv ahoiit \'2.') per cent. Tin- jfrouiul water rose more in l!)2r) in proportion to tlic canal siipi)ly I'ct't'ivcd tlian would have been ex]>ected from 11h' records of the preeedinj; years. The iii'ound water in 192.") was an avt'i-a^c of i> feet lower than in 1922 for all of the Alta District. A canal supply of 105,000 acre-feet in 1922 resulted in maintaining the ground water witiu)ut a rise or lowering. A canal supply of 156,000 acre-feet in 1925 resulted in an average rise of the ground water of l.H feet. For a drainage factor of 12.5 per cent this would i-ei)resent 26,000 acre-feet of water placed in ground water storage and a remaining use of 180,000 acre-feet. Apparently the lower ground water in 1925 has resulted in a reduction of outward ground water movement and evaporation from areas of formerly high ground water of about 35,000 aere-feet so that a smaller canal supply will re.'-tilt in a rise of the ground water under the conditions of 1925 than was required in 1})22. Additional periods of record .should be secured before dependence is placed on the numerical amount of the indicated difference. Tliese results, however, are sufficient to indicate that a smaller canal supply will maintain the ground water under the ground water conditions obtaining in 1925 than would be required under the conditions of 1922. The canal supply in 1925 less the indicated accumulation of ground water storage was at the rate of 1.6 acre-feet I)ei' aci'e of cropped area. Hydrographs of Typical Wells. IIydrogra))hs of typical wells are shown in Fig. 12. Well 1 is in ('(>ntei"vilh' bottoms near the head of the Alta ('anal. Very little lowering has occun-ed. Well 30 is near Kings Rivei*, just north of Reedle>'. iia])id lowei-ing after the end of canal diversion is shown. Part of the lowering in 192-1- Mas recovered in 1925. Well 102 is six miles south of Keedley and 2 miles from Kings Kiver. Less wide fluctu- ations are shown than in well 30. Well 2() is 5 miles northeast of Reedley and away from the river. A lowering of 18 feet occui-i'cd in 1924, of which only 4 feet was recov- ered in 1925. Well 93, 2 miles south of Dinuba, is in the Central area. The ground water prior to 1924 rose close to the ground surface. Well 99. in the southeast ])ai't of the district, shows less effect from canal delivery with about 10 feet lowering in 1924. Well 150 is in the Button Canal area, near the eastern boundary of the district. There is little irrigation in this area and little monthly fluctuation is shown. (Jradual lowering has continued during the period of record. Well 152 in the Traver area shows the effect of canal delivery in 1922 and 1923 and of its absence in 1924 and 1925. The ground water rose to within 3 feet of the ground surface in 1922 and 1923. GROUND WATER IN AREA UNDER KINGS COUNTY CANALS. The term Kings Count.v (yaiuds is generally used to describe the }*eople's Last Chance and Lemoore canals, which serve adjacent areas on the south side of Kings River in Kings County. These canals serve an area having a relatively old irrigation development. Th(» crops are diversified and include trees, vines, alfalfa, grain and pasture. Much 74 Department of J^uhJic Works. of the area lias had a rolatively liii-li water table and a larger portion of the land is used for pasturage on this aecouiit than in some of the other Kings River areas. Ground water records are not as extensive under these canals as for the three upper districts. Some scattered records are available for earlier years. .More extensive records were begun in the Lemoore area in 1924 and in the Last Chance and People's Canal areas in 1925. The diversions by these canals are larger in proportion to the area irrigated than the practice on Kings River as a whole. Judged by the resulting ground water conditions, the diversions have exceeded the crop moisture requirements. This has resulted in a rise of the ground Avater to the extent necessary for excess soil evapora- tion to balance the surplus sujiply. Little outward movement of ground water appears to occur as the adjacent areas in the direction of the ground water slope as shown on Map No. 1 do not have available shallow ground water supplies. The depth of ground water and the closeness of the material also increase from the upper toward the lower portions of the area itself. Lemoore Canal Area. The Lemoore Canal serves the most westerly part of this area. Ground water slopes into the Lenioore area from the Last Chance area on the east. Some surface waste occurs at times into the channels of the South P^rk of Kings River on the west, but there is little indication of ground water moxemeiit into such channels. The ground water fluctuations reflect the variations in tiie canal supply as shown in Fig. 18. The ground w'ater in the ditferent parts of the area follows a similar variation; that in the southern part of the area averages about one foot lower than the ground water in the central and northern i)ortions. in some areas the ground water rose to within 4 feet of the surface. The divei-sions in ^\)2y> were 9o.0()0 acre-feet. For the gross area of 52, 300 acres the diversion averaged 1.82 acre-feet per acre. This supply resulted in a net average rise of the ground water of 0.2 foot; appar- ently the diversions in 1925 wci-c adequate to supjily the crop needs and any lo.sscs by soil evaporation that may have occurred due to Jiigh ground water. While all of the gross area is classed as irrigated in the crop survey of this area, a con.siderable area of pasturage receives only partial service and the average use on the remaining area would be above the figure given. Based on the one year's records for 1925 a diversion into this area of 1.8 acre-feet per acre of gross area will apparently supply crop needs and maintain the ground water under exi.sting con- ditions including the incomplete irrigation of present areas of pasture. A rate of diversion in excess of crop needs would be expected to result in a rise of the ground water until the excess soil moisture evaporation balanced the excess in supply. Present pumping in this area is not as extensive as under many other Kings River canals. Twenty-three pumping plants Avere operated in 1925, having an average capacity of one second-foot. These wells are u-sually 40 to 100 feet deep. One well, 1517 feet deep, had a discharge of 3.2 second-feet. Ground Wafer Eesources, Southern San Joaquin Valley. 75 Last Chance Area. Tills area lies bt'tweeii the Li'iiioore and People's Canal area. The irross an'a is ;5;118(> aeres, all of which is classified as more or less com- pletely irrigated. The proportion of pasture is less than that in either of the adjacent canals. Seventy-five pnmping plants are reported as operated in 1925; tiie larger part of these were installed in 1!)2-1:. The wells are relatively shallow, varying usnally from 40 to 100 feet in depth. The average discharge is somewhat less than one second-foot. The depths to ground water in this area increase from north to south. The fluctuations reflect the canal supply. Ground water slopes into the area from the People's Ditch area on the east and out from the area to the Lemoore area on the west. The ground water fluctuates with the o V a i C 3 O a o a. V TJ V at J O JAN. FEB. MAR. APR. MAY JUN. JUL. AUG. SEP. OCT. NOV. DEC. Legend. t//Ay/ A Canal diversion in acre-feet. Average depth to ground water in feet FIG. 13. Relation between canal diversions and change In level of ground water in Lemoore Irrigation District, in 1925. canal deliver\', as shown in Fig. 14. In 1925 the ground water rose within 4 feet of the surface in some wells. For the whole area the ground water was 1.1 feet higher at the end of 1925 than at the heginiiing. The total diversion was 63.740 acre-feet, or 1.92 acre-feet per acre of gross area. Deducting the probable amount of water represented by the rise in the ground water, the one year's records for 1925 indicate a use of water by the crops of 1.65 acre-feet per acre of gross area. Hates of diversion in excess of crop use w^ould be expected to result in a rise of the ground water until evaporation from the .soil balanced the excess supply. People's Ditch Area. The gross area under this canal is 65,600 acres ; about 40 per cent of this area is pasturage, the remainder being a])out e(iually divided between orchard and vines, alfalfa and grain. 76 Department of Piihlic Worls. Oronnd water rcfords were not be^im in tliis area until August, 1925. The depth to ground water for the re::iaiuder of 1925 varied froiii 9 to 11 feet. As these depths are greater than those for tlie same months in the adjacent Last Chance area, it is pro])able that the water in the People's Diteh area was also lower during the summer months than in the Last Chance area. The number of existing pumping plants in this area is not known, although little development has taken place. General conditions are similar to those in the atl.jacent Last Chance area and shallow wells giving a discharge of al)out one second-foot should be obtained. GROUND WATER IN VALLEY TROUGH AREAS ALONG CHANNELS OF KINGS RIVER. NORTH SIDE Tills area includes the lands along Fresno Slougli. It includes the Stinson, Crescent, James and Tranquillity irrigation districts and the 4 ■J o IS i ■o c 3 O b a q a •> O o c n> O JAN. FEB. MAR. APR. MAY JUN. JUL. AUG. SEP. OCT. NOV. DEC. Legend. Y//A///\ Canal diversion in acre-feet * ' * Depth to ground water in feet. FIG. 14. Relation of canal diversion to change in level of ground water in area served by Last Chance Canal, in 1925. Cuthl)ert-I^urrell area. Pumping is practiced by both the Stinson and James districts as well as In- individuals. Cuthbert- Burrell Area. For the Cuthbert-liurrell area, ground water records for about 30 wells are available since August, 1922. The ground water contours shown on ^Fap No. 1 indicate that ground water may move into this area from several sources. The direction of ground water slope from the western part of the Consolidated Irrigation District is toward this ai-ca. Water diverted by the Liberty niid P>ig Mill Iv'acc <'ana]s iniulil nl^o rc;tcb the ui'oimd water in tliis Ground Water Resource.^, Southern San Joaquin Valley. 77 area. Oonoral irrouiul water in the ^Furpliy Slouf;h area inehuling the Lai^'ima and Ixivcfdalc In-iiralion districts slopes partially toward this area. In 192.'} an average lowerinu: of 0.6 foot oecurred; in 1924 the lower- ing was 8.25 feet. In 192.') the flow of Kings River was ahout 80 per cent of normal ; in 1924 ahout 25 per eent of normal. In 1925 with about 70 per eent of normal run-off an average lowering of 2.4 feet oecurred. These amounts of lowering appear to he due to the deficiency in run-off of these seasons. Stinson Irrigation District. This district has 6 wells 800 to 1000 feet deep, which were formerly artesian, and IH wells mainly 500 to 600 feet deep. These are used during the portions of the season when Kings River is not available. The district contains about 11,000 acres. The district was organized in 1921. The artesian wells were drilled prior to organization: the sjiallow wells have been installed by the district. In 1925 the total pumping draft was 9924 acre-feet. The average discharge per well for both the deep and shallow wells was ahoiit 2 second-feet. Sufficient records are not as yet available foi- these wells to enable an estimate to be made of the rate of draft which they can maintain without gronnd water de])letion. The cpiality of these waters has been previously discnssed. It is desirabl(> that other water should also be used on the same lands in order that harmful effects may be avoided. Crescent Irrigation District. This district has not installed pumping plants as a part of its water supply. There is only limited development by individuals in this area. One well 1130 feet deep furnishes a good yield. Ground water con- ditions appear to be generally similar to those in the Stinson District. James Irrigation District. This district operates wells 900 to 1200 feet deep located within the district as well as securing water from Kings River and from shallow v.'ells to the east. The deep wells are perforated below the 700-foot level. One well, 1850 feet deep, encountered gas and salt in the lower portion in such (|uantities that 240 feet in the bottom of the well was plugged off. A second well, 4570 feet deep, has been abandoned because of the gas and brine produced. Tests on a num])er of these wells were made in September, 1918. The ])ressure level was from 9 to 10 feet above the ground surface and si()[)ed from the souHieast toward the northwest, following the general direction of the local drainage. The rate of slope averaged 1.1 feet per mile. Thirty-four deep wells were operated by the James District in 1921. In other years the number has varied with the water suj^ply secured 78 Department of Pubiiv Works. from other sources and the erop needs. The average results for 1921 to 1924 urc as follows: Averaf/e Mean Average Number of discharge operating operating loells per well, lift, all wells. lift for J/ wells Year operated second-feet feet operated each season X!»21 34 2.08 28.6 19.6 1922 11 2.08 25.0 23.6 1923 14 1.89 32.6 30.5 1924 24 1.54 39.3 37.8 Two I'esults are shov/n for the averafro lift. One is tlie averaii'o of all wells observed in eiich season, the number of records being less than the number of plants operated, as the water stood below the pump liowls in sonu' wells and could not be observed. The last column gives the avcrauc of four wells observed in each of the four years. The total draft in 1924 was 11,80U acre-feet. The four wells continuously read show a lowering of 18 feet in foui* years. Summary. Xearl.\' all the ground water development in this area is from deep \vells, shallow wells being used oidy in the Cuthbert-Burrell area. The term deep well is used for those wells itenetrating strata of impervious material replenished from more distant sources, rather than from streams oi' irrigation adjacent to the well. Water in such deep wells is under pi-essure. Such wells in this area were artesian in the past and may How at present in periods of small draft. The relationship of shallow ground waters to local conditions of canal or stream supply is usually direct and positive, as indicated by the preceding discussions for other areas. The relationship of deep wells is indirect and more difficult to trace, particularly in quantitative terms. Ground water contours for deep wells indicate the direction of slope. However, fluctuations of deep wells reflect mainly changes in pressure head rather than depth of lowering of ground water and com- parisons of draft and depletion can not be directly made. Water from deep wells is obtainable generally on all of this area as well as along Kings River to the east. The depth generally increases toward the west. Wells within the Consolidated District penetrate heavy clays and enter water-bearing strata at 'SOO to 400 feet, which is under pi'e.ssure and in some cases formerly flowed. Wells recently drilled west of the Consolidated District, near Cando, reached similar strata at depths of about 500 feet. Wells formerly artesian were secured in the Riverdale area at depths of from 800 to 1200 feet. The ai'tesian wells in the James District are from 900 to 1200 feet in depth. The details of the valley formation even to the depths penetrated by these wells are not known. There appears to be a sufficiently continu- (nis im])ervious strata over mucli of this area to retain the pressure of the ground water in the underlying sti-ata. This impervious strata may have been deposited when the valley was sul)merged and may conform to the topography of the valle\- at that time. This suj)i)Osition might account for the less depth at which such impervious strata are pene- trated nearer the eastern side of the vallev. I Ground Water Resources, Southern San Joaquin Valley. 79 No outeroi)s of tlic watcr-bearinp: strata from which such deep wells draw liavo liccn found or rocogni/cd. It is ])rol)al)le that they do out- crop under more recent alluvium near the eastern side of the valley, or that the upper edges of the im|»ei-vious strata have been eroded expos- ing the underlying pervious strata to sources of absorption. The extent of such absorbing areas and tlie amounts absorbed are unknown. There is no information to indicate any source of absorption within the older formations of tiie upper stream courses and any water so absorbed must apparently be obtained below the points of measurements of the streams and so be accounted for in the recoi-ds of visible water supply. As previously discussed the available data do not indicate any material outward ground water movement from the area as a whole. If such deeper water-bearing strata have no outlet and are filled with water under pressure no movement of water through such strata would occur under natural conditions. For such conditions the static head should equal the elevation of the source of supply. As the static levels in the deep wells have a slope some movement is indicated. Such movement, however, is probably relatively small. The natural conditions are changed when wells are drilled into such deeper strata and pumping occurs. The discharge creates velocities toward the wells which require a lowering of pressure to overcome the friction of the water movement. Such lessening of pressure may be marked during pumping with quick recovery when pumping ceases. Strata under pressure may recover their static level more (piickly than surface strata, where actual filling in of the area depleted is required. It is more difficult to secure observations on deep ground water than on shallow sources. Deep welLs are necessarily expensive and in conse- quence are operated more nearly continuously. Idle wells for observa- tional use are not usually available. Operating wells reflect the influence of their own drawdown rather than static levels. In the Kings River area deep wells are relatively sensitive to draft. The stopping of flow in wells at a distance of over two miles when other wells are pumped has been observed. Such lowering is the result of lessened pressure due to the friction head required to produce the dis- charge of the i)umped well. These conditions together with the eflfect of the present pumping from deep wells indicate that the amount of draft obtainable from deep wells in this area without excessive lowering is probably not as large as that obtainable in areas having favorable shallow ground water supplies. GROUND WATER IN WEST SIDE AREA FROM TULARE LAKE TO MENDOTA. This area covers the portion of the valley extending for about 50 miles along the west side of the north and south channels of Kings River. The width below the 300-foot contour varies generally from 6 to 8 miles, and includes a gross area of 250,000 acres. No canal service is received within this area, the canals on the west side of the stream channels being within the area classed as the Yalley Trough. Present development is entirely from deep wells. 80 Department of Public Works. Within the IMondota IrriLiatioii District in the northern portion of the urea 27 wells supplied 13, ()(>() acivs in IDlM. These wells yield 2 to :{ second-feet each. Tlie\' are l"rom 1200 to IHOO feet deep and are per- Icrated only heh.w depths of 600 to 800 feet. The Boston Land Co., irrigates ahout lo.OOO acres near Westhaven. of wiiich ahout one-half is in trees and vines, and onedialf in annual cro])s. Inclnding other developments, such as those of tlu' Kin.iis County Development Co., west of Wheatville and near Murray, the total area now heing supplied l»y ])umps exceeds 80.000 acres or ahout one-eiiihth of the lirass area. It is tlifficult to secui-e readings on the ti:round water, as practically all wells are operated nearly continuously. No attempt has heen made (»n Map No. 1 to draw ground water contours for this area. In Water Supply l*aper 898 general ground water contours are shown. These were hased on the shallow wells then availahle in 1907 and show a slope from the west towai'd the east as would he expected for waters derived from the west. Such scattered records as are availahle indicate that the deep ground water prohahlx' had some slope from the west to the east, particnlarly in the southei-n portion of the area. Present records indicate varying amounts of change. Cnder j)uiuping contlitions, the slope appears to he from the east to the west. The availahle records do not fully show the amount of lowering that has occun-ed. Such records as are avail- ahle indicate a matei-ial lowering in some j)oitions of the area, the low- ering heing larger in the areas of heavier draft. The (luality of the water in this area has l)een discussed in Chapter II. The water from shallow wells is not availahle in sufficient (piantity to furnish a good irrigation supi)ly : hy perforating only the deeper strata it is not used. The quality of the deeper water varies. These variations are not regular, hut the water tends to he hetter in the southern part of the area than in the northern part. The incompleteness of the availahle data makes any discussion of the ground water supply of this area unsatisfactory. The large cost of wells and the uncertainties of the supply, hoth as to quality and quan- tity, make development in this area hazardous. With only one-eighth of the gross area developed, lowering appears to he occurring. What- ever source of replenishment this ai'ea may have it is relatively distant. In other area.s remote from sources of ground water supply, the ground water has been found to he sensitive to heavy draft. There is no reason to expect different results in this ai'ea. Development in this area should he undei'takcTi only hy those understanding the conditions and ahle to afford th(^ I'isks involve(l. GROUND WATER IN TULARE LAKE AREA. This area covers the bed of Tulare Lake and adjacent low areas. It lies south of the area under the Kings County canals and Avest of the outer Kaweah and Tule areas. Oii the southwest the hills api)roach the lake area. The division between this area and the one to the south is made at the so-called Sand Ridge in township 24 south. The area of the Corcoran Irrigation District is included, although this is only partly within the area of Tulare Lake. Ground \Wi((r licaovrces, Southern San Joaquin Valley. 81 Tulare Lake receives tlic surplus run-off of the Kern, Tule and Kaweali rivers and such portions of the surplus run-off of Kings River as Hows south. The area sulimerged varies widely. Hefore reclamation of Ihe lake Ix'd began, at hiuh water stages ahoul ."iOO s(juare miles were suhmerged. Keclanuition has heeu gradually extended by the construc- tion of levees enclosing additional ai'cas until nearly all of the lake bed i« now more or less completely reclaimed. The last large inflow into the lake occurred in li)16. The larger part of the reclamation work has been accomplished since that date. The surface soil of the lake bed is underlaid generally by a tight clay which prevents percolation into or out of the lake. The lake has l)een dry in recent yeai's. due to the less tlian normal run-off that has occurred. Over most of this area, ground water is obtainable only from deep wells. In Water Supply Paper 398 the ground water conditions in the eastern portion of the area Avere discussed. It was found that water from depths varying from 100 feet near Corcoran to 500 feet about 8 miles to the west was too highly alkaline to be suitable for use for irri- gation. Water from wells from 1200 to 1800 feet deep near Corcoran was found to be suitable for irrigation. Deeper wells in the main lake area were not available at the time Water Supply Paper 398 was [)repared In discussing the change in quality of water from shallow wells between the delta areas to the east and the lake area, a line of division was shown between the areas in which the two types of water occur. The line passed through Lemoore, Corcoran and Angiola. This has come to be known locally as the '"Mendenhall fault" — Mr. W. C. Men- denhall being the principal author of Water Suppl.y Paper 398. This division was not descrilxnl as a fault in 'the sense of being a line of movement but was the location of a change in quality of ground water. The difference was explained as being due to the difference in the nature of deposit of the materials, those to the west being lake deposits containing alkalis, due to the evaporation from the lake; and those to the east being delta deposits not subject to such factors. Deeper water from wells considered to come from depths below those resulting from lake conditions did not show such differences in quality. Wells less than 500 feet in depth are regarded as shallow wells in this area. Until recently this shallow water has not been used to any extent. In those areas in which such water could he secured its quality frequently made its use undesirable. Ground water development was by deeper wells u]> to 2000 feet in de))th from which both the quantity and (puility were much better. The use of such deeper puini)ed water and of some canal supi)ly in the Corcoran District has resulted in the establishment of a new source of supply for the shal- low water table and some I'eccnt wells are now drawing on this source. Such shallow wells are sui)i)lied by the |)ercolation lo.sses from other uses. The available records do not show the extent of fluctuation that has occurred from the present draft on these wells. The amount of draft that can be supported would be expected to be G— 4707C 82 Department of Public Works. limited to the amount of the percolation losses from other uses. As the canal supply is iri'cguiar and the deep wells are used on only a portion of the district area, the extent of draft which can be sup- ported by the shallow ground water can not be expected to provide a permanent sup{)ly for a large area of additional land. To such extent as the shallow supply can support a pumping draft it repre- sents a desirable reuse of other sources. Deep wells have l)een used in the area of the Corcoran Irrigation District for considerable periods. Such wells were formerly artesian. Wells several miles to the east of this area also Howed until recently. As mo.st of the deep wells are operated nearly continuously it is difficult to secure readings representing the standing level of the deeper ground water. General data indicate that the levels, while pumi)ing, have lowered 30 to 50 feet in recent years. Kecent develop- ment has been in the northern and eastern portion of the area. in the northern portion of Tulare Lake wells of about 1800 feet deptli are used. These wells arc usiuilly perforatf^d below 600 feet depth and yield 2 to 3 second-feet. Such wells frequently contain gas. Analyses of Avater from four wells showed low sulphate content, indicating that their source is not irom west side materials. The amount of bicarbonate and chloride was larger than desirable. Wells in the .southwestern portion of the lake have not encountered water in suftieient amount for irrigation. Wells are not in use in the southern portion. Some deep wells are in use in the southeastern part of the area. The Alpaugh Irrigation District conveys its main supply into its district from wells in the area to the south. Pumping of deep welLs sontli of Corcoran has been practiced longer than in other parts of the area. Wells 1300 to 2000 feet in depth are used giving disdiavges of about 3 second-feet. Ground water in this area now stands 30 to 60 f'^et ])elow the surface in some wells which formerly flowed when not pumping. Present ground water is from 100 to 120 feet below the ground while pumping. The larger part of this lowering has occurred during the last four vears. Qround Vi,'ater Resources, Houlhern San Joaquin Valley. 83 CHAPTER IV. GROUND WATER IN TULARE COUNTY AREAS. This area includes the lands dependent on Kaweah and Tide rivers and Deer and AVhite creeks. It is the same area covered by Bulletin ;] of the Division of Enj,aneering and Irrigation published in 1922. The following discussion is based on the data collected in the prep- aration of Bulletin 3 and records that have been secured since its completion. The earlier observations include those begun in 1917 by the Lindsay-Strathmore Irrigation District over most of the Kaweah River area. These were extended to cover the whole count}^ by this office beginning in 1920. Later observations of ground water over the whole area were made by the Division of Engineering and Irri- gation in the fall of 1922 and 1924. Arrangements were made with ^Fr. C. H. Holley of Exeter, California, for the use of certain ground water records which he had secured in the course of his private practice over a large part of the territory covered by the Tulare County investigations of this office. These observations began in 3 916 and have been continued to date, and have been made available for use in the preparation of this report. The conclusions stated in this report are based on the author's study of all of the records available to date in this area. About 550 welLs were included in the earlier investigations and aliout 800 wells are being measured by Mr. Holley, the records covering periods beginning in 1917 to 1920 for different parts of the area. The available records are considered to furnish an adecjuate basis on whicli to determine the effect of pumping in this area. The obligation of this office to all of those who have assisted in making available ground water records is gratefully acknowledged. Good yields are obtained from wells of relatively shallow depth in almost all parts of the Tulare County area. The depths are greater in the higher parts of the area adjacent to the foothills. As shown by the statistics of irrigation, ground water development has been active in nearly all parts of the area. In many instances the ability to secure satisfactory rates of discharge from wells has been accepted as an indication of an extensive and permanent source of supply. The ability to pump water from underlying materials depends on the coarseness of such materials and the ease with which they yield water. Sucli water may be drawn from the accumulations of long periods of time. A good discharge from a Avell does not of itself indicate any regular source of supply. Without adequate sources of supply, heavy pumping can only result in the gradual lowering of the ground water. The ground water conditions in the dilferent parts of Tulare County vary widclx' and a discussion of general or average conditions lias little value. The direction of slope and elevation of the ground water are shown on Map No. 1; the depth to ground water on Map No. 2 ; and the lowering from 1920 to 1925 on Map No. 3. in the discus- sion the area has been divided into smaller areas representing differ- ences in the conditions of ground water use and supply. These areas 84 Department of Public Works. are the same as tliose used in Bulletin 3, the later records enabling the results of Bulletin o to be brought down to date. GROUND WATER IN KAWEAH RIVER AREAS. The conditions of water supply and use on the Kaweah River areas were discussed in det;iil in Bulletin No. 3, covering data available to the end of 3921. The run-olf of the Kaweah Iliver at Three Rivers for the period 1890 to 1921 was estimated as an average of 438,000 acre-feet per year. The run-off for each year since 1921 has been as follows: 1921-22 461,000 acre-feet 1922-23 363,000 acre-feet 1923-24 102,000 acre-feet 1924-25 325,000 acre-feet The addition of these four years to the period 1890 to 1921 results in an estimated mean annual run-off for the period 1890 to 1925 of 427,000 acre-feet. In addition there is some rim-off, estimated as an average of 13,000 acre-feet per year, from the drainage area below Three Rivers, giving a total mean annual run-off of 440,000 acre-feet. Kaweah River is divided at ]\IeKay Point into the St. Johns and Kaweah channels. Divei-sions are made from both channels. Water entering the Kaweah Channel in excess of the diversions therefrom may reach Tulare Lake either through Cross Creek or by way of Elk Bayou and Tule River. Water flowing through St. Johns River without l)eing diverted enters Cross Creek and may finally reach Tulare Lake. The records of flow leaving the Kaweah Delta were analyzed in Bulletin 3 with the conclusion that such outflow under existing conditions of use would have averaged 55,000 acre-feet for the period 1890 to 1921. Practically no outflow has occurred since 1922. The estimated mean annual outflow for the period 1890 to 1925 becomes 50,000 aci'e-feet when the years since 1921 are included. Not all of .such outflow would reach Tulare Lake as there are diversions on both channels between Tulare Lake and what is considered as the outer edge of Kaweah River Delta. Several canals divert from both the St. Johns aiul the Kaweah channels. An analysis of tlie diversion records in Bulletin 3 indi- cated a usual total simultaneous diversion of about 1900 second-feet. Sustained lun-off in excess of this amount was found to produce out- flow from the delta. Les,ser amounts of run-off produce outflow except in the main sunnner months. The areas served by tlie different canals are, in .some cases, over- lapping and it is not i)Ossible to separate the areas served and the ground water supply for each oan;d. The area irrigated varies in different years with the extent of the stream flow. The usual area found to be irrigated by canals alone in 1921 was about 102,000 acres with an additional area of about 26,000 acres which received some canal irrigation and seemed a supplemental supply by pumping. Similar data for 1925 have not l)ecn secured. There has not been mueh change in the total area of about 128,000 acres receiving some canal .service except as the run-off' has varied in each season. How- Ground Water liesources, Southern San Joaquin Valley. 85 ever, there lias 1>ihii a material increase in the proportion of this area which has been provided with facilities for piimpintr to supplement llie canal suj){)ly. This increase in supplemental pumjiing is the result of the small run-olf of recent years as well as the general tendency toward more comi>lete utilization of the land. Including lands receivint;' only pumping service it was estimated that the total area irrigated in 1920 wdiich was dependent on Kaweah River for its water sui)])Iy was 175,000 acres. The increase in this area since 1920 has not been large, although no complete statistics are available. Ground Water. Fairly complete records of the fluctuations of the ground water on the Kaweah Delta are available since early in 1917. These records cover all of the delta except the westerly portions lying beyond the areas served by canals. Records covering the Avesterly portion of the area were begun in 1920. The extent of the stream flow entering and leaving the Kaweah Delta has been discu.ssed. The surface stream flow of Kaweah River is considered to ])e the only source of w^ater supply of material extent now reaching this area. Similarly the surface outflow is considered to be tlie only wMtev leaving this area of material amount. The basis for this latter conclusion was discussed in detail in Bulletin 3. The ground water slopes in the adjacent Kings River areas indicate that outward ground water movement from the Kaw'eah River northward under the Kings River Ridge does not occur wdthin the depths reached by existing wells. The ground water in the Kaweah Delta during the winter months of minimum use was found to rise by an amount which varies with the extent of the winter stream flow. If material outflow oecui-red, lowering of the ground water would result in such months of minimum su])])ly. The material encountered in wells liecomes flnei- ln\v;ii'd the oulei' edges of the delta. The finer texture of the surface strata on the western portion of the delta would limit, if not entirely prevent, any movement in these strata. There have becm no visible natural outlets foi' ground w^ater move- ment into Tulare Lake as the lake becomes dry in years of deficient stream flow. All of these factors combine to support the conclusion that all of the run-off of Kaweah River absorbed within the Kaweah River Delta is available for use in the delta. The Kaweah River area has been divided for purposes of discus- sion. The divisions are based on conditions of use and supply. The main area of the delta includes the area within which canal service is received, although only a portion of the total area actually receives such service. There are some canals which divert from Kaweah River and serve lands mairdy above Venice Hills. The areas so served are segregated from the main canal area below Venice Hills. There is also an area considered to 1h^ a part of the Kaweah Delta which does not receive canal service. This is the outer or western pr)rtion of the delta. The area between the Lindsay-Strathmore lii'igation Dislrict and Klk Baxon. whih^ not originally a part of the Kaweah Delta. ,ma\- now receive urouiid water from the delta, due 86 Department of J'nhHc Worhs. to the lowering' of the wain- 1al)l(' within the area with a reversal of the natural j^round water slope as shown on Map No. 1. The general conditions for each of these four areas for 1921 are as follows: Summary of Areas Irrigated and Pumping Draft for Kaweah River Areas in 1921. Areas servctl onlv by canals are not included. Total Averaf/e rstiniatrd draft net draft in acre- Areas Irrigated from feet, per acre. Gross By By ground For area For area, candl and pumping water. irri- gross Area acres pumping only acre-feet gated area Main area of Kaweah Delta covered by canaLs diverting , „„„ , ^ „ ,- forlandsbelow Venice Hills 190,000 18,900 37.400 So. 000 1.5 0.4o Area covered by canals divert- ing mainly for lands above Venice Hills 60,000 6,900 9,700 27.000 1.6 0.4.) Area of lower Kaweab Delta outside of areas covei'd by canals 9.5,000 100 14,900 31,000 2.1 0.30 Area west of Lindsay-Stratli- more Irrigation District toward which ground water slopes from the Kaweah Delta 20,000 7,300 19,0fi0 2.6 O.S.'i Totals 365,000 25,900 69,300 162,000 1.7 0.45 The heaviest puiiipin,i;' draft occurs in the ai'ea west of the Ijind- say-Strathmore District, where the sources of supply are the most indir(H*t. The followinji' tahle suniiuarj/es the average ground water fluctua- tions for each of these areas for the period covered hy the available records. The fluctuations for the lower delta area have been esti- mated for the tlrst three years shown: Summary of Average Fluctuations of Ground Water, In Feet, in Kaweah Delta Areas 1917-1925. Avcraoc Fluctuation for Period Total inn- J91S' 1919- 1920- 1921- 1922- fU>',- or Area 19 IS 1919 1920 1921 1922 192'i l»2.' Mean Main area nf Kawi'ali Delta covered by canals diverting for lands below . . , Venice Hills- —2.5 —2.1 —0.1 —0.8 -|-1.3 —7.0 —0.6— 11. S -Areas covered by canals diverting for lands mainly above Venice „„_ „„. ,«,«. Hills —0.9 — 0.9 — 0.2 —0.8 — 0.25 — 6.3o —1.0 —10.4 Area of lower Kaweah Delta outside of areas , un- covered by canals —3.2 —2.7 —1.3 —1.8 — 0.2o —3.0 —3.. — li).9.. Area west of I>ind- s a y - Slrathmorc Irrigation District toward w h i c h g r o u n d water slopes from the „ „„ „„ „, „. . Kaweah River-__ —2.2 -2.1 —0.8 —1.3 —0.9 -9.3 -.3.4 -20.0 Mean —2.2 — 2.0 —0.4 — 1.0 -|-0.o —6.0 —1.6 —12.7 Total run-off of acre^fe^et ^-^!!!- 237,000 281,500 377,500 373,500 475,000 232,000 32.5,000 318,000 Rainfall at Visalia, ,,o<. c en inio o -?« inches 8.07 8.85 9.32 8.56 11.26 6. 89 10.38 8.78 ^^draft,^'Vcr^e"-f2et-^ 124,000 133,000 142,000 162,000 170,000 200,000 210,000 168,000 Ground Water Rcsovrces, Southern San Joaquin Valley. 87 The seasons used end Noveinl)er 1. The fluetnations for 1923 and 392-1 are combined, as readings were not secured in 1923. The run- off, rainfall and draft for the two years are the annual average in each case. The figures presentcMl in tlie preceding table represent the general I'esults since 1917, hut of themselves alone furnish little basis for conclusions regarding the relative draft and supply. The entire period of eight years contains but one year. 1922, in which the run- off equalled the mean and this year only exceeded the mean by less than 10 per cent. The grouiid water depletion that has occurred varied in the four diffeivnt parts of the area as well a.s within the areas themselves. For the eight years the ground water for the whole Kaweah Delta has averaged to lower 1.6 feet per year. The average run-off retained in the delta for the same period has been 78,000 acre-feet per year below the normal. The average lowering per year over the gross area of 365,000 acres would represent a depletion of 77,000 acre-feet per year of ground water storage if an average drainage factor of 12.5 per cent is assumed. For 1925 a shortage in the supply retained within the delta of 65.000 acre-feet resulted in an average lowering of 1.6 feet. This lowering with a 12.5 i)er cent drainage factor represents 73,000 acre-feet for the gross area considered. This indicates that for the area as a whole the average water supply retained will about support the present acreage. The increase in pumping plants in recent years has been largely for supplemental pumping on lands receiving canal irrigation. Dnt to the lowering of the ground water natural subirrigation no lunger occurs and artificial subirrigation or pump- ing is now required. Sucli pumpi)ig has not increased the actual draft on the gdoimd water as comjiared with past use with high water table, to the same extent as pumping for new areas would increase the draft. The areas within which the ground water rose in 1922 and 1925 are shown on Map No. 3. Any area showing a rise in 1925 would be expected to fully maintain its ground water during a series of normal years. The ai'ca showing a rise in 1922 would also be expected to similarly nuiintain its ground water except for the marginal parts of the ^rea. The conclusion would appear justified that with average run-oft' in the Kaweah River the Avater supply will support the existing development if it can be distributed so as to reach all parts of the area. Any material increase in area will be expected to result in a deficiency in supi)ly even in a period of normal years with resulting gradual ground water lowering. This statement concerning average conditions should not be interpreted to mean that the ground water will be maintained in all parts of the delta with present development and noi-mal run-off, as the present distribution of use is such that many parts of the area do not receive the supply needed locally even in normal years. The occurrence of a series of normal years can be exjxcted 1o restore the ground water within the area receiving direct canal service. Sucli areas would be expected to recover the full low- ( ring of the ])a.st eight years Avith resulting conditions of high water 88 Department of Public Works. table before reeoNeiy is shown in the outer oJ' more heavily pumped areas. Such local conditions can best be discussed by individual areas. The results in the Kaweah Delta appear to furnish an answer to the question of whether greater or k^ss lowering of the ground water will occur at the outer edges of a delta than near its apex under con- ditions of pumping di'aft which exceed the supply. The ground water in a delta occurs on a slope from the apex toward the outer edges. The argument has been made that with heavy pumping resulting in ground water depletion, the ground water would be drained out from the apex more rapidly than from the edges so that there would be les« lowering in the outer areas. This argument does not find support in the Kaweali Delta records. The maximum low- ering has occurred in those areas near the outer and lower edges of the delta wherever heavy pumping has been practiced with little local canal service while areas near the upper portion of the delta where replenishment occurs by percolation from the stream channel and canal use have shown only a small lowering. MAIN AREA OF KAWEAH DELTA COVERED BY CANALS DIVERTING FOR LANDS BELOW VENICE HILLS. This area represents about one-half of the gross area of the Kaweaii Delta. It includes nearly all of the areas receiving canal service and over half of the area receiving pumping supplies. Due to the distribution of the diversions from the KawH>ah River over this area, it shows a mort^ (piick recovery of its ground water than areas not so supplied. Within the area the relative proportions irrigated l)y canals and by pumping varies so tiiat differences in the response to the stream flow are quite marked. Increase in pumping since 1921 has been mainly to supplement canal use rather than as an entire source of suj)p]v. The number of plants increased 20 per cent from 1924 to 1925. Map No. 8 shows the total ground water lowering that has occurred from 1920 to 1925. Occasional areas having favorable priority of canal rights and receiving good supplies even in dry years, show no lowering even during this period of less than normal run-oft'. In general the line of five-foot lowering encloses the areas receiving canal service of regular character Pumping in such areas is less extensively developed and canal use more nearly meets crop needs. Any portion of the Kaweah Delta which has not lowered more than 5 feet during the past 5 years of below nornud run-oft' would be expected to fully maintain its ground water under existing con- ditions of development in years of normal supply. The lines of 10 feet or larger lowering of the ground water during tiiis period represents the outer portions of the area where a small percentage of the gross area receives canal service, or where the late priority of the canal results in wider variations in the supplies I'eceived in dift'erent years. The diversions of such canals as the I'ackwood and Tulare Irrigation District tiuctuate widely in differ- ent years. Deficiencies in canal supplies are overcome by larger amounts of piunping. Wide fluctuations of the ground water in such Qround Wafer Ersfnircm. S^ottfJur)} San Joaquin Valley. 89 areas are to be expected. Lowering: in years of ])elo\v normal run-off may not indicate an overdraft if it is balanced ii.\' the rise in the years of above normal run-off. There has only l)een one year of normal sui)i)ly in the period 1920 to 1925. In 1922 the ground water rose over practically this entire area, the ris^e being as large as 6 feet in the area of largest previous lowering near Tulare. p]ven with this gain in 1922. the total change for tlie past 5 years in this local area has been a lowering of 15 to 20 feet. The supply in 1922 was less than 10 per cent above normal for the whole river; the diversions of the Tulare Irrigation District exceeded its average by more than this amount, however. The diver- sions by the Tulare District in 1922 were larger than the total diver- sions for the three years 1928 to 1925. Ilydrographs of typical wells are shown in Fig. 15. Well L-2 is located about 4 miles east of Yisalia along upper Deep Creek in an area which receives adequate canal service. The ground water in 1925 was as high as in 1921. A quick response to the divereion of water into Deep Creek and adjacent canals is shown. The ground water is fully maintained in this area under existing conditions. In years of more than normal run-off the ground water may rise suffi- ciently close to the surface to cause injury. Wells M-22 and M-IG show the contrast between areas receiving regular canal service and those receiving service only in years of large run-oft'. Well ]\r-22 is located 3 miles east of Tulare in an area served by the Farmers Ditcli. The run-oft' in 1922 which was only about 10 per cent above normal nearly restored the accumulated lowering from 1917 to 1921. The ground water held its elevation in 1925. In this area no lowering of the ground water over a series of years is to be anticipated under a continuation of present conditions. Well M-16 is located four and a half miles west of Well ]\I-22, in the I)umping area west of Tulare. Lowering is shown in all years except 1922. In 1922 the Tulare Irrigation District secured sufficient diver- sion for the irrigation of some lands in tins vicinity. The lowering of 1920 and 1921 was more than recovered in 1922. The lack of canal supply and the heavy pumpinir resulting in a lowering of about 20 feet in the 3 years froln 1922 to 1925. Well ]\I-16 illustrates the dependence of the ground water on direct local supplies. The ground water less than 5 miles to the east, as illustrated l)y Well M-22 has shown a total lowering of only 8 feet from 1922 to 1925, during which the run-oft' of Kaweah Kiver has averaged only 60 per cent of normal. The supply received around Well ^1-22 has not enabled Well M-16 to maintain its level. AVell i\I-16 is only maintained when canal water is brought into its own area. The future fluctua- tions of Well ]\I-16 will depend on the amount of canal water that may be diverted into its vicinity. Well N-11 is about 7 miles west of Tulare, near the end of Pack- wood Creek and at the west edge of most of the pumping in this vicinity. The ground water held its own in 1922. In other years it lowered. A larger lowering occui-red in 1925 in proportion to the run-oft' in Kaweah Kiver than in j)revious years. This reflects the greater tendency to lower in this area with the increased draft of recent years. The canal diversions into this area are limited and it m Department of Public Works. WELL L-2. Along upper Deep Creek. WELL N-n. Near end ol Packwood Creek. 20 25 30 35 40 >^^' :^ ^ .192? isgo ' — — . « 1922 B- o-o p Ja2^ "-^i ____ "^^ ^ -♦ WELL M-22. Three miles east ol Tulare, u (0 5 10 ■D C 2 Ol 15 20 2 5 10 o 15 20 a v O 25 30 35 40 45 WELL M-16. One nfiile west of Tulare. z mococ >:2-Joo.i->o ll.5<5-,->0 robably reflects the effect of th(» increase in draft. Of the total diversions only part reaches the lands within the district, the con- veyance losses being heavy. Apparently an annual diversion of about 45,000 acre-feet is needed to maintain the ground water Avithin this district. Improvements in conveyance will reduce the diversion required. The records seem to justify the conclusion that in years of normal or above normal run-off", present development will not result in a ground water depletion for the main area of the Kaweah Delta cov- ered by canals diverting for lands below Venice Hills as a whole. The average rise in the ground water in 1922 within this area of 1.3 feet will about account for the excess supply of that year. In normal years the ground water in the ai-eas undei- the canals having earlier rights will rise and in a series of wet yeai's will pro})ably again approach nearer to the surface than may be desirable. For the outer areas, the extent to which the ground water may reeover losses in dry years by the gains in wet years will depend on the extent to M'hich actual diversion into such areas occurs. The whole showing of the ground water records in this area emphasizes the necessity for bringing surface supplies into each part of the area if the ground water is to be maintained. The sup])()rt of the ground water in all n.arginal portions of this area depends on the diversions into such 92 Department of Public Works. areas rather than the filling of the delta as a whole. The ground water may rise in the npper portions of the delta until drainage is needed without causing a rise in the outi-r ai'eas not receiving canal supplies. Only 55 per cent of the gross acreage in the main Kaweah area is now irrigated. The preceding conclusions api)ly only for this extent of development. If all or any considerable part of the remaining 85,000 acres not irrigated should be placed under irrigation the present relations of the supply and draft would be changed and the conclusions stated would no longer apply. AREAS COVERED BY CANALS DIVERTING FOR LANDS MAINLY ABOVE VENICE HILLS. The area considered under this heading is shown on Map No. 1. The division lines are not definite, but the area includes the lands whose ground water appears to be derived from the Kaweah River above Venice HilLs or from canals diverting from the upper portions, of the river. Near botli the St. Johns and Kaweah channels some areas are sub- iri'igatcd. Little pumping for local use is practiced on these lower laiuls. The pumping plants of tlu' Lindsay-Strathmore Irrigation District are located in this area; the water ]iu!nped is used within the district near Lindsay and Strathmorc. For the M'hole area, the area receiving pump service increased 25 per cent from 1921 to 1924. The number of pumping plants increased 10 per cent from 1924 to 1925. The ground water contours on .Mnp No. 1 show a slope of the ground water into the nortliem })art of this area from above Venice Hills between Ihe hills and Cottonwood Creek. For the four years, 1917 to 1921, an average lowering of 'A.6 feet occurred. A lowering of from 1 to 4 feet occurred in 1922 and ;5 to 5 feet from 1922 to 1924. Kecords for 1925 in tliis area ai-e less complete. A lowering of over 10 feet from 1920 to 1925 has occurred in parts of this area. The present draft appears to exceed tlu* supi)ly now reaching this portion of the area and continued lowering is to he anticipated. Well li-54. Fig. 16. is north of tlie main Kaweah Delta in an area of scattered pumping. A continued gradual lowering is shown. No gain was shown in 1922. Tliis well appears to be located sufficiently far away from streams or canals so that it is but slightly affected by the character of the season. The slower rate of lowering appears to be due to the small draft in its vicinity rather than to a dependable ground water supply. On the south side of the river the larger pumping area is in the soutlieastern part of township IS south, range 25 ea.st. Some irriga- tion from c?inals is i-eceiveil. Yukohl (*reek also crosses the area. From 1917 to 1921 an average lowering of 13 feet occurred under an area of 3000 acres of the heavier pumping. The drop in 1921 for tlie same area averaged nearly 4 feet. From 1920 to 1925 a total lowering of about 15 feet occurred. Tlie development is relatively complete in this area, 2460 acres of the gro.ss area of 3000 acres being Ground Water Resources, Southern San Joaquin Valley. 93 irrisratod in 1921. Tlio present rate of draft exceeds present sources of sujjply and continued loweiing is to be anticipated. AREA WEST OF LI NDSAY-STRATH MORE IRRIGATION DISTRICT TOWARD WHICH GROUND WATER SLOPES FROM THE KAWEAH DELTA. This area covers the portion of the cone of depression brought about by local pumping which lias a slope from the Kaweah Delta as shown on INIap No. 1. The portion sloping from the Tule River areas has been separately discussed. The area in the Lindsay-Strathmore District is not included. The present direction of tiic ground water slope as shown on Map No. 1 in this area is the reverse of that existing prior to pumping. The pumping has resulted in such extensive lowering that the ground water slopes into the area from all directions. Prom 1920 to 1925 the average lowering has ])een 20 feet. There has been a relatively small increase in the development during this period. Lowering has occurred in all years. The pumping occurs mainly in the northern end near Exeter and in the southern portion west of Lindsay. The northern portion is nearer areas using Kaweah Ixiver water and the lowering has not been as large as in the southern portion. Well K-8, Fig. 16. is located between the two main areas of pump- ing at the north and at the soutli ends of this area. Continual lowering is shown, amounting to 11 feet from 1920 to 1925. This is a less amount of lowering than that in the areas of heavier pumping to the north or to the south. Well K-8 is about 3 miles east of Outside Creek. The ground water held its level in 1922. Well R-28 is Avithin the Lindsay-Strathmore Irrigation District. Its fluctuation reflects the history of the water siipply of this area. Pumping occurred in 1917 with a resulting heavy lowering. The use of district water in 1918, 1919, and 1920 resulted in a recovery of nearly all the lowering in 1917. Further pumping since 1920 has resulted in a total lowering of about 40 feet. This well illustrates the inability of the local ground water to support pumping draft. For the Avhole area, from November 1 to February 1, of the seasons 1917 to 1921, the ground water rose an average of about 3 feet, or at the rate of 1 foot per mouth. This rise appears to be larger than that for the remainder of the year, as rates of draft of 1 acre-foot per acre of gross area have resulted in lowering of 2 feet per year. The total lowering to date exceeds 80 feet in some parts of this area. The gi'eatest lowering has occnri'ed within five miles of areas along Outsidt» Creek that have lowered less than 5 feet in the deficient years from 1!)21 to 1925. Even with this excessive lowering ground water movements do not appear to have been established which will supply the jircsent draft. The average lowering in 1925 was greater than that ill ciliicr 1!»18 or 1919, although the stream flow was larger in 1925 than in cilher 1918 or 1919. The more rapid lowering in recent years may lie partially the result of resuming pumjiing fi'om wells in the Lindsay- St i-athmoif Oisti'ict to the east, wliicli were not operated in 1917 and 19 IS. D4 Department of Public Works. WELL B-54. North of canal area in scattered pumping. WELL 0-3. In pumping area ttiree miles southwest of Goshen. 20 25 30 35 40 • QO' } ..J92I. .- — m L». I2i^ «> ^-*. 192i ♦■> "^ .. 192'' >♦ ■^ J925__ ♦ WELL K-8. Tliree miles south of Exeter. C WELL D-10. Near Cross Creek away from canals and pumps. 10 15 tl?25^ 20 1921 T954 92? WELL N-21. Formerly artesian. WELL R-23. Two miles southeast of Lindsay. z CD oc cc > z ^ CJ a-' !-■ > d < 2 -, r> 3 u o o _ z; -. < 1/3 O Z Q 5 10 15 20 25 30 o^ \ •1 922 \ \ o ■"X ^ _ 192 L 1 •1 924 192 ) WELL 0-10. Two miles east of Corcoran. z CO c oc z -J o ft- t- > o increase in the use of ground -svater in recent years. Well O-IO is a shallow well 2 miles east of Corcoran. Little fluctua- tion occurred from 1920 to 1922. Some increase in the rate of lower- ing' is shown since 1922. Shallow wells have not been used very largely for irrigation in this area, although some use is now being made of such wells to the west. With the increase in development since 1922, the recurrence of years of normal run-off will be expected to result in lowering over this entire area. Only continued lowering can be anticipated in this area as its distance from direct sources of replenishment prevents its receiving a sufficient supply to maintain the present draft. Any further increase in use can only be expected to increase the rate of lowering and shorten the time when the increased lift will result in ]uimi)ing being no longer profitable. GROUND WATER IN AREA IN LINDSAY-STRATH MORE IRRIGATION DISTRICT. This district includes about lil.OOO acres near the eastern edge of the valley lii'tween Kaweah and Tulc rivers, it is too far from the :ircas irrigated fioiu citlK r sti-eam to have received ground water from such sources. The locally tributary drainage area has a very limited I'un-ofi'. Pumpinu' for citrus orchards began about twenty years ago. Such pumping resulted in a lowering of the gi-ound water. By 1915 ■ he water secured from some wells had become too alkaline for use without injury to the trees. Outside soiu'ces of supply were sought, the irrigation disti-ict organized and a system securing Avater by pumi)ing from ai'cas along Kaweah Hiver constructed. The substitu- tion of the new source of supply for local pumping resulted in recovery of the ground water in some wells. In recent years some piim|)iug from wells within the district has been resumed. The lesulting ground water conditions vary in different parts of the dis- trict (\\ie to local factors of use. The experience in this area fully demonstrates tlic iiia(lc(piacy of its local sources of ground water within the district to luaiulai;! tlie draft re(|uircd for the area now deve!op''d. GROUND WATER IN AREAS DEPENDENT ON TULE RIVER FOR THEIR WATER SUPPLY. The area de])endent on Tule Hi\-er for such water supply as it may receive extentLs on th.e north to the center of the cone of ground water depn^ssion produced by the pumping west of Lindsay and to the Kaweah Kivei- areas; to the west to the area considered to represent I Ground Water lifsonrccf!, ^nufhrm San Joaquin Valley. 97 flic ireneral iiiin^U'd fjround waters of the San Joaciuiii Valley trouf^h ; to file soutli to the Deer Creek area and to tlie east to the line of eontaet of the granite and the valh'v till or to the area eonsidered to be dependent on Lewis Creek. A portion of this area is served by canals diverting from Tule Kiver. Such replenisliment as the leniainder of the area may receive is indirect by general ground water movement. The boundaries of the area are indefinite and there is l>rol)a))ly little effect from Tule River on the ground water of the outer portions of the area. In 1921 63,700 acres were found to be irrigated within this area. Of this area al)out 2800 acres depended entirely on canal service for their water supply: and 14,000 acres received both canal and pumping service; the remaining area depended entirely on pumping. There has been little change in the area served by canals since 1921, except as this varies from year to year with the extent of the run-off. For the whole area, there was little change from 1921 to 1924 in the area served l)y pumps. Some decrease in area occurred particularly in the irrigation of pasture. In 1925 an increase of about 4500 acres occurred due mainlv to the irrigation of additional areas of cotton. Run-off of Tule River. The run-off of Tule River was discussed in detail in Bulletin 3. The sum of the run-off of the main Tule River and the South Fork for the period 1890 to 1921 was estimated to be an average of 137,000 acre- feet per year. The discharge for the years since 1920 has been as follows : 1920-21 90,500 acre-feet 1921-22 141,600 acre-feet 1922-23 102,200 acre-feet 1923-24 26,600 acre-feet 1924-25 87,000 acre-feet The records for the South Fork are not complete for these years. Missing records have been estimated by comparison with the main Tule River. The addition of the last four years to the period 1890 to 1921 results in an estimated mean annual run-off for the period from 1890 to 1925 of 132,000 acre-feet. Diversions by Canals. Available canal diversion records were discussed in Bulletin 3. ContinuoiLs records of the diversions are not maintained. Except in years of large stream flow, practically all run-off is diverted. There has been no outflow in Tule River since 1921. It is estimated that outflow occurred in eleven of the last 36 years, the average amount being 15,000 acre-feet per year for the entire period. As there has been no outflow during the years covered by the ground water observations, the run-off of Tule River represents the water supply available for this period. The available data does not permit the diversions to be estimated for different parts of the area served by canals so that it is treated as a whole. 7—47076 98 Deparimeni of Pithlic Works. Ground Water Fluctuations. 'riic averai;*' .uroiuid \va1i*i' Hiict ualioiis I'lif tin- whole area art* sliown ill the following tal)lt' : Gronnd water finvtiialinnF! in feet Per cent nf f/ro.ss area Xoi\ 1920 Nov. 1921 Xov. 1922 Nov. 192', Nov. 1920 irrUialcd to to to to to nivisionof (iriu in 1921 Xov. 1921 Xov. 1922 Xov. 192) Xov. 1925 Xov. 192i) North Tule 44 — 3.0 — 0.7 — 11.4 — 4.0 — 10.1 Main Tule ;!,s — 1.5 +1.j — 7.7 — 0.!) — 9.0 South Tule 12 — 1.75 — 0.15 — 4.2 — l.ti — S.O Outer Tule 24 —1.8 — 1.2 — 5.!i — 3.0 — 11.9 M-liole Area 31 — l.S — 0.25 — 7.1 — 2.3 — 11.45 Itun-off of Tule River in acre-feet 90,500 141,600 64,400 87,000 The above table shows wide variations in the fluctuations for the (litt'erent areas and years. These variations retleet the conditions in eacli area. It is necessary to discuss the o round water conditions .separately for such divisions of the area. GROUND WATER IN MAIN TULE RIVER AREA INCLUDING THE AREAS WITHIN WHICH SOME LANDS RECEIVE CANAL IRRIGATION FROM TULE RIVER. This area includes all lands i-eceiving any irrigation from Tule River except those below the junction of Elk Bayou and Tule River. In some years excess flow in Tule River may reach areas adjacent to Tulare Lake: this has not occurred in the years covered by the ground water records. The principal irrigation from Tule River occurs in the upper por- tion of the area from Porterville to Woodville. The canals in the lower portion of the area receive only irregular service. The data have been divided into three areas representiuu' the upper, middle and lower portions. In 1921 the areas irrigated were canvassed and data on the pump- inu' draft secured with the following results: Area irrigated entirely Estimated Per cent Estima ted draft. Gross or i)artly gross of gross acre- fret ner a eve of area, hy pumyinfj. draft. area gross h^igated acres acres acre-feet irvic/nted liven area Upper lands ea.st of west line of Range 27 East 26,200 8,365 20.900 32 0.80 2.5 Lands in Range 26 East 28,800 11,167 21,100 39 .75 1.9 Lands west of Range 26 East 21,800 76,800 6,623 10,400 30 34 .50 0.7 1.6 Totals 26.155 52,400 2T0 Additional area receiving only canal service 2,805 28,960 38 In the upper area orchards, mainly citrus, were the more extensive crop, Avith alfalfa grown on the next largest area. In the middle area there were less trees l)ut more vines, with a larger area in alfalfa than in any other crop. Alfalfa and pasture jiredoininated in the western portion. In 1924 the total area receiving puiu]) service had increased Ground Water Resources, Southern San Joaquin Valley. 99 ()iil\ slightly, Ihc increase's and decivases in dilfiuvnt parts of the area nearly balancing. In 1925 there was an increase of al)out 1700 acres. Tlie Hnetnations of the <;ronnd water I'or the five years, 1921 to 1925, are as follows : Average fluctuations of the f/round water in feet Year Upp&r portion Middle portion Western portion 1921 — .35 —1.20 —3.30 1H22 — .2 +2.0 -fl.25 1923-1924 — 6.7 —9.0 —7.5 1925 +2.3 — 2.2 — 2.G Totals — 4.95 —10.4 — 12.15 In the upper area Tuh^ River and Porter Slough as well as the diversions by canals result in a more direct recharge of the ground water with a consequent smaller lowering. Even with the below normal run-off of 1925, the ground water rose over nearly all of this area. The records indicate that with normal run-off' this upper area as a whole will maintain its ground water with present development. However, while this statement is considered to be correct for the area as a whole, it will not apply to all parts of the area. Heavy pumping in local areas not receiving canal supply would be expected to result in progressive lowering. In the middle ai'ea the increa.se in the area supplied by pumping since 1921 resulted in a greater lowering in 1925 than in 1921 with about the same run-off in Tule River. A sufHcient proportion of the larger run-off in 1922 reached these lands to result in a rise over nearly the entire area. The low^ering in 1923 and 1924 exceeded that in other portions of the Main Tule area. The lands receiving canal service are distri])uted over nearly all of this area. The present rate of pumping draft is larger than in the upper area. The available records do not cover years of normal run-off under present rates of draft, so that the effect of normal run-off is difficult to predict. The lowering in 1925 probably reju-esents a ground water depletion of about 12,000 acre-feet. Tlie run-off in 1925 was about 50,000 acre-feet below normal. This area should receive one-fourth or more of the dif- ference between the run-oft' in 1925 and the normal run-off so that the ground water would be expected to be maintained in a normal year. It would appear that the present draft can be supported by this area without continued ground water low^ering, the gains of normal or w^et years balancing the losses of dry years. However, any material increase in draft w^mld probably result in progres.sivc lowering par- ticularly in the portions not receiving direct canal service. In the western area, the tluetuations in different years are less con- sistent. Less lowering occurred in 1925 than in 1921. A rise occurred in 1922. Diversions into this area have been very small in the years shown except in 1922. Th(> increased lift has tended to decrease the draft which prol)ably explains the decreased lowering in 1925 as com- pared to 1921. Judged by 1922, normal I'un-off should maintain the ground water in this area. TIk^ maintenance of the ground water will be dependent on the actual How of the river and diversion by canals wdthin the area rather than by general ground water movement into the area. In 1921 with very little stream flow or diversion within this area, the draft can be accounted for by the ground water lower- 100 Department of Public Works. WELL T-10. Two miles south of Woodville In edge of canal area. WELL T-3. One mile northeast of Well T-19. WELL T-19. On Tule River near Woodville. u n t 3 ■a c o E o 15 WELL U-50. On lower Tule River. a. o a 20 25 30 35 40 *m. '♦n ''■ ^ 3 — ». ^ J^i "■ / ^*« 19 22. & 192 4 y^D .(l92 > — — ♦ WELL S-2A. South of Tule River in canal area. 5 10 15 20 25 . ^o _- — o- 192 n^ 7 ^'^ — ♦( N- *^ 1922 *^ 1 ^■>. .-^' WELL X-23. South of Tule River outside of canal area. 30 35 40 45 50 -o-^ 1920 1 LI92L„ r-^c 1 1 1922 t 4 — . » -♦- — * a 192' -^ - ♦-^ -♦s .Jp ♦ WELL S-22. Four miles northwest ot Porterville. 1917 LEGEND. 1918 1919 1920 1921 1922 WELL S-6. Near Porter Slough. z iDii:a:>:z-idt^i-i>o FIG. 17. Hydrographs of typical wells in Main Tule River Area. Ground Water Resources, Southern San Joaquin Valley. 101 ing. The same is true in 1925. In 1922 only 10 per cent of the run- off of Tule River would need to reach this area in order to supply the draft and account for the jjround water rise that occurred. These general comparisons indicate that no large item for movement of ground water into the area is required in order to account for the tiuetuations. Such movement, if it occurs, would occur slowly and would represent only a limited quantity per year. These results are another illustration of the dependence of ground water on direct and local sources of supply rather than on distant movements. Ilydrographs of typical wells are shown in Fig. 17. Well S-6 is near Porter Slougli and canal irrigation in the area west of Porter- ville. It recovered tlu' lowering of 1924 in 1925. In years of normal run-off this well would be expected to fully maintain its level. "Well T-19 is the same as Well 1331 of the Lindsay-Strathmore Irrigation District, so that records since 1917 are available. It is located on Tule River in the middle portion of tlie ^Main Tule area. In 1917 normal run-off resulted in a high ground water level in this well. Lowering occurred in the following dry years to 1922 when nearly all of the loss was recovered. Larger lowering occurred in 1923 and 1924 with some net loss in 1925 and 1926. In April, 1925, a short flow occurred in Tule River at this well which resulted in a marked rise. The amount of this flow was not sufficient, however, to maintain this gain and there was a small net lowering in 1925. With normal run-off this well would be expected to recover its former levels. AVell U-5() Ls along Tule River in the lower portion of the Main Tule River area. It recovered in 1922 but has lowered continuously since. Recovery is to be expected in any years in which flow in Tule River reaches this portion of the river. Over a series of years of average run-oft' this well would be expected to maintain its level. AVell S-22 is located in the northern part of the upper portion of the ]\Iain Tule area. Canal irrigation is received to the east of this well. Lowering has occurred in each year covered by the records. The normal run-off in 1922 resulted in small lowering. This well shonld hold its level in years of above normal supply but would not be expected to gain sufficiently in such years to balance the lowering in subnormal years and a continual lowering is to be anticipated. Well T-3 is 1 mile northeast of AVell T-19. Continuous lowering has occurred except in "1922. The rise shown by AVell T-]9 in April. 1925, did not reach AVell T-3. Unless pumping draft is too greatly increased, this well would be expected to maintain its levels over a series of normal vears. AVelLs S-24, X-23 and T-10 are all located south of Tule River and illustrate the dift'erence in lowering that results from varying con- ditions of canal supply. AVell S-24 is about 1 mile south of the river and under the Poplar Ditch. It rose in 1922 and showed a relatively small lowering in 1923 and 1924. The supply in the Poplar Ditch in 1925 resulted in a rise over 1924. No permanent lowering is to be expected in this well. AVell X-23 is three miles southeast of Poplar and away from canal irrigated lands. It did not gain in either 1922 or 1925 and has lowered 15 feet in the five years from 1920 to 1925. Continued lowering in this well is to be expected even in years of 102 Department of Public Works. normal run-off. Well T-10 is in the southern portion of the area receiving canal service south of Woodville. A small gain was shown in 1922. No recovery occurred in 1925. In normal years this well would probably maintain its level, although the increase in pumping since 1922 may have changed the conditions tlien existing. Over a series of years having average run-off in Tule River this well would be expected to show some continued lowering. GROUND WATER IN AREA ON NORTH OF TULE RIVER DELTA. The area toward which the ground water now slopes from Tule River, as shown on Map No. 1, differs from that toward which the ground water sloped prior to pumping due to the cone of depression that has been caused by the pumping draft. The development began prior to 1912. A total of 10,530 acres out of a gross area of 23,700 acres were irrigated in 1921. This represents a development of nearly one-half the gross area. The area irrigated increased to 11,900 acres in 1924. As there are no direct stream supplies or canal use in this area, such a large proportion of development would be expected to result in rapid depletion of the ground water. Ground water observations were begun in this area in 1917 by the Lindsay-Strathmore Irrigation District. The average results for all years of observation are shown in the following table : Season endinu Nov. 1 of 1917 Mean lowering of the ground water 4.0 Mean rise of ground water from Nov. 1 to Feb. 1 of year listed l.S 1.9 2.7 3.4 1.5 Riin-off of rule River, totn.l acre-feet 120,100 50,900 76,400 111,800 90,500 141,600 64.400 87,000 Rainfall at Portervillc, inches 11.65 1918 3.9 8.12 1919 3 5 10.25 1920 _ 3.1 10.67 1921 3.0 9,49 1922 .7 13.32 1923 8.36 1924 11.4 5.27 1925 4.0 12.00 Total or mean 34.2 10.06 (long time mean) A tendency toward a larger recovery during the winter season was shown in the earlier years. The observations since 1921 have not been sufficiently frequent to determine the amount of winter recovery except for 1924-25, in which fifteen wells recovered an average of 1.5 feet. Although the ground water slope into tliis area was steeper in the winter of 1924-25 than in the earlier winters, there does not appear to be any greater recovery due to such steeper gradient. As the winter of 1924-25 was one of irregular rainfall with more pump- ing than is usually practiced, further records are required before positive conclusions can be drawn. The lowering in 1925 was larger than in 1918, 1919, or 1921, although the run-ott' was similar or larger in 1925 than in these earlier years. The only year having normal run-oft', 1922, showed a lowering. The larger rainfall in 1922 probably reduced the pumping draft. These records and comparisons indicate that a general average lower- ing of about 4 feet per year can be anticipated in this area and that « Ground Waiir RcsDurce!^, Southern San Joaquin Valley. 103 tlie lowering- will tend to be more uniform from year to year than the run-olf of Tule River. Well P-15. Fig'. ]8, is located in the southwestern portion of this cii'ea, about 5 miles from Outside Creek on the Kaweah Delta and one and one-half miles from AVell T-3, Fig. 17. in the Tule River area. It is more favorably situated in relation to these sources of supply than the average for this area. ]\[aterial lowering has occurred in all years since 1917, excejit 1922. While some recovery may occur in years of excess run-off, such recoveiy can not be expected to equal the lowering in years of less than normal supply and progressive lowering under existing conditions is to be expected at this well. Well Q-13 is located ne^ir the nortli side of this area and about in the center of the cone of depression. Only records for ]924 to 1926 are available. These show a material lowering in each of these years. GROUND WATER IN SOUTH TULE AREA. This area includes 7000 acres lying south of the area reached by canals diverting from Tule River and north of the area that may be affected by Deer Creek. Only 860 acres or 12 per cent of the area was irrigated in 1921. In 1924 the area irrigated had increased to 1130 acres. Practically all the development is in the eastern portion of the area and consists of citrus orchards. The ground water has lowered less in the last five years than in any other outer area adjacent to Tule River. The amount of the low'ering increases from the north to the south The gross draft in 1921 was estimated as 2780 acre-feet or an aver- age of 3.35 acre-feet per acre irrigated. Some of this probably returned to the ground water. If the net draft is assumed to be 2 acre-feet per acre or 1720 acre-feet per year, the average lowering over the gross area would supply the full draft without any inflow if the drainage factor is 15 per cent. Continued lowering in this area is to be anticipated. Unless the area irrigated is increased, how^ever, the average rate of lowering to be expected will require a relatively long period before the costs of pumping become excessive for the present crop. The smaller rate of lowering appears to be due more to the small proportion of the area which is developed than to any direct source of ground water supply. Well Y-3, Fig. 18, is located in the center of this area and west of the pumping area. The lowering shows a tendency to increase in amount; with a similar amount of run-off in Tule River in 1921 and 1925, a lowering of two feet occurred in 1925 as compared "vnth no lowering in 1921. 'o GROUND WATER IN OUTER TULE RIVER AREA. This area lies southwesterly from the area which receives irrigation from canals diverting from Tule River. The data have been divided so as to .show the results in the eastern and western portions sep- arately, this division being made on the west line of range 25 east. The eastern portion covers the part of the Tule River Delta from Pixley to Tipton, extending eastward to the area covered by canals. 104 Deparimeni of Puhlic M^orks. WELL U-44. In pumping area between Tipton and Pixley. WELL 0-30. In pumping area southwest of Tipton. 50 55 60 65 70 75 "> <^Pn ^C -— h-1^ ^^^0 1922' ♦s Ss 1924' "^-s 1925 »1 )26 35 40 45 50 55 60 -*, ►^^ .— — 92( -•- -0 \ — J921 1 "0 -^ "' 1922* .11924 1 WELL P-15. At south edge o( north Tuie area. o IS "t in ■o c 3 o X a. u O WELL V-12. North of Aluaugh. formeily artesian. 5 10 15 20 25 30 35 ^ \ ^ \ ^ l i if > O O D 3 UJ (J O u T ^ < W O Z O 25 30 35 40 WELL V-8. West of Pixley at edge of pumping area. .—>• ; 22i ♦-* 1920 , — ~o \ 19^22« 4 192 i WELL 0-13. In north Tule area. 60 65 70 1926 Y^ WELL Y-3. In south Tule area. ^33 1917-«- 1918~*- 1919-0- LEGEND. .,- 1920 — 1-- — ■ -"- 1921 — -^^ — - 1922-'-i-- ► - 1924 -.i- :- 1925--*-. -■ 1926 FIG. 18. Hydrographs of typical wells in Outer Tule River Area. Ground Wafer Resources, ^onlhern San Joaquin Valley. 105 Tlic wosterii portion includes the area which may receive its ground water supply from Tulo River sources, l)ut which is situated relatively distant from any channel or canals supplied by Tule River. The western boundary of the area i.s the division between ground water derived from Tule River and that derived from general mingled sources and is necessarily indefinite. The canvass of pumping in these two areas in 192] gave the follow- ing results: Per Estimated draft , Estunufcd cent acre- feet pi") acre 'I'otal area Gross gross of gross of of irrigated, area, draft, area gross irrigated aci'es acres aere-feet irrigated area area Eastern portion 12,366 40,400 31,660 31 .80 2.5-'. Western portion 10,988 56,300 20,480 20 .35 1.85 Totals 23,354 96,700 52,140 24 .55 2.25 In 1921 the development in the eastern portion consisted largely of alfalfa with a marked increase of vines in the preceding year. In the western portion alfalfa and pasture were the main crops with only small areas of orchards or vines. In 192-1 the area irrigated had decreased about 10 per cent from the area in 1921, due mainly to the decrease in the area of pasture. In 1925 the area increased so as to .slightly exceed that of 1921. The average fluctuations of the gi'ound water during the five years, 1921 to 1925, have been as follows : Average lowering of the ground ivater in feet Year Eastern portion Western portion 1921 2.25 1.55 1922 1.4 1.0 1923-24 6.0 5.85 3925 3.5 2.1 Totals 13.15 10.50 As in the case of other Tule River areas, a larger lowering occurred in 1925 than in 1921, although the run-off of Tule River was practi- cally the same in these two years. Lowering occurred in 1922 with a run-off slightly above normal. The rate of draft on the eastern portion of the area in 1921 was similar to that on the upper area receiving canal service, the lowering was six times as large as in the canal areas. In the western portion the rate of draft was less than half of that in the upper canal-served area, the lowering was over four times as large as in the canal area. These comparisons show the greater sensitiveness to draft of outlying areas not directly supplied by surface flow and demonstrate the ranch smaller rate of draft which such distant areas can maintain without continued lowering of the ground water. In 1921, information was secured from the owners of fifteen wells covering the fluctuations in the preceding 5 to 15 years. The lowering \aried from 14 to 29 fci^t and averaged 21 feet. The larger number of tlie wells were in the western portion of the area. For Ave of the wells in the eastern portion of the area tlu' lowering varied from 17 to 25 feet. Ilydrographs of typical wells in this area are shown in Fig. 18. Well U-44 is located in the pnmjiing area extending from Tipton to 106 Department of Puhlic WorJis. Pixley. Continued lowering i.s shown. The lowering has been fairly uniform per year, being about the same in 1922 with above average run-otf in Tule River as in the other years of less than average run-off. AVell V-8 is about 4 miles southwest of Well T-ll and Avest of the main pumping area. Less find nation is shown. Well V-12 is two miles south of AVell V-8. It was fonneily artesian, but stood over 30 feet below the ground surface in November, 1925. From 1920 to 1922 littl(> actual lowci-ing occurred, the cycle of fluctu- ation corresponding to that usually sliown by wells in i)ressure strata with a reduction of pressure during the summer season of draft and a winter recovery. Conditions of increased draft since 1922 have resulted in a lowering of about -W feet from 1922 to 1925. Well O-;}0 is southwest from Ti])ton in the ])umping area. This is a shallow well and shows coutiuued lowering, although the amount of such lowering is less than in tlic deeper well, A^-12. The W'clls in the western portion of this area "were formerly largely artesian. Wells which formerly flowed have not flowed for several years, some sliglit flow may occur during the wi)iter months of mini- nuim pumping draft. The present estimated draft iu tliis whole area is about 48,000 acre- feet per year or about 35 per cent of the mean annual run-off of Tule River. The ground water slopes from the main Tule River area, but the rate of slope and character of the material are not such as to indicate the movement of any such large proportion of the Tule River supply into this area. The extent of use and the ground water fluctu- ations indicate that lunirly all the Tuli> River supply is retained and used within the nuiin Tule River area. The ground water lowering from 1921 to 1925 represents the drain- age of a soil volume of 1,140.000 acre-feet. The total net draft at 2.0 area-feet per acre for the same five-\'ear period w'ould be about 235,000 acre-feet. If the drainage factor is assumed to be 12.5 per cent based on data from other similar areas, the ground water lowering would account for 140,000 acre-feet, leaving a total of 95,000 acre-feet or 19,000 acre-feet per year to he supplied by ground w^ater movement into the area. While such a comparison is necessarily open to uncer- tainty in its numerical items, the general result appears reasonable. It is doubtful if a ground water movement of more than 20,000 acre- feet per year into this area occurs. This is less than half the average draft for the past live years. The ground water in this area is only indirectly affected by the annual variations in the run-off of Tule River. More lowering has occurred in dry years than in seasons of larsrer run-off. However, the years of larger run-off' are also years of larger local rainfall. Increased rainfall tends to decrease the draft due to the smaller amount of irrigation applied. The ground water is at too great a depth for direct penetration of rainfall to the water table to occur. The continuation of the present pumping draft in this area can only be expected to result in an average ground water lowering of about 2 feet per year, even with average rainfall and run-off. In dry years larger lowering is to be expected ; even in Avet years some lowering is to be anticipated. Ground Water licsources. Southern San Joaquin Valley. 107 GROUND WATER IN DEER CREEK AREA. This area includes those lands whicli appear to be dependent on the run-off of Deer Creek for such surface and ground waters as may be available. It lies between the Tule River and White Creek areas, and extends from the foothills to the general minoled ground water of the San Joa(iuin Valley. Like other areas its boundaries are not definite and some mingling of the ground water from adjacent sources may occur in the outer portions. The estimated mean annual run-oft' of Deer Creek is 19,000 acre-feet as previously discussed. This with the run-off of such lower hill areas as are tributary to this area, estimated as not to exceed 1000 acre-feet, gives a mean annual water supply of 20,000 acre-feet. There is some direct use of Deer Creek for irrigation, but much the larger portion of the run-off reaches the ground water. Including the area irrigated in the Terra Bella Irrigation District, a total of 15,500 acres were found to be irrigated in 1921. The area irrigated in the Terra Bella District increased from 3840 acres in 1921 to 4680 in 1925. The area irrigated in 1924, including that served by the Terra Bella District, is estimated to be 19,000 acres, or an increase of about 20 per cent since 1921. The area irrigated in 1924 represents only 18 per cent of the gross area of 106,000 acres. The delivery in the Terra Bella District has averaged 1.5 acre-feet per acre cropped. The use on citrus orchards has varied from 1.75 to 2.0 acre-feet per acre. Under individual pumping plants where the wells were able to supply larger quantities, the average amount pumped was found to be about 3.0 acre-feet per acre in 1921. The following table shows the relation of the lowering to the run-off of Deer Creek. Observations of the ground water were not made in 1923, so that it is necessary to combine the seasons of 1923 and 1924. The run-off of Deer Creek is taken from measurements by the Terra Bella Irrigation District: Average Run-off lowering of the of Deer creek. Period ground loater in feet total acre feet November, 1920, to November, 1921 1.9 11,440 November, 1921, to November, 1922 .95 16,480 November, 1922, to November, 1924 4.6 *9,360 November, 1924, to November. 1925 2.4 *iI'Soa Entire period November, 1920, to November, 1925_- 9.85 *12,780 * Mean annual run-off for the period. The lowering for 1921. 1922 and 1923-24 is inversely proportional to the run-off of Deer Creek. The effect of the increasing draft is >,hown by a comparison of 1922 with 1925. Although there was a larger run-off in 1925 than in 1922, an average lowering of 2.4 feet occurred in 1925 as compared with 0.95 feet in 1922. The averag_e lowering in 1923 and 1924 was ])raetically the same as that in 1925, {dthough the run-off in 1925 was nearly twice as large as the average for 1923 and 1924. As the run-off in 1925 was nearly normal, an average lowering of a1)ont 2.5 feet per year can be expected under l)resent conditions of draft in this area, even in \ears of average run- oft'. Onlv a small area along the upper course of Deer Creek rose in 1925. ■ 108 Department of Puhlic Works. WELL V-3. At west end of Ocer Creek area away from pumping. WELL X-1. Adiacent lo valley welts of Terra Bella Irrigation District. 35 40 c 45 0) o (S 50 3 n 55 •a c 3 o E o 35 1. u 40 45 o 50 a u 55 WELL W-14. At Earhmart. 1 — ♦ ♦— r*- r — — 1 """■* ~"?92r ^1920" — -' 1922* *s V 1924 -igff V, ^♦-1 »-'' ^^« "^ 1925 i WELL X-36. In Sec, 3. T. 23 S.. R. 26 E.. M. D. B. & M. Area of small pumpmg draft. — — ■~^< — — — , ♦ - — * 1920 - J — 19^1 *• 1£ 22 1 >■■ , ►ii 25 A 192 \ -^- ~- 19 26 30 35 40 45 50 WELL X-10. In Sec. 27, T. 22 S.. R. 26 E.. M. D. B. & fVI. In area of local pumping west of Terra Bella District wells. • »^ ~,. 1 1920 -. /J W' ^ 1922 • 1924 WELL Y-32. In Terra Bella Irrigation District. WELL Y-22. North of Deer Creek in upper part of area. ZBiiroc>;z-JOo.>- >o ->u.5<2->-'o 0'*' ->u.5< S-j-'<<'>020 LEGEND. 1920 — » . — 1924 1921 — o '— 1925- 1922 --' -— 1926 FIG. 19. Hydrographs of typical wells in Deer Creek Area. Ground Water Resources, Southern San Joaquin Valley. 109 Tlio total draft for the whole area was estimated to be 35,000 aere- feet in 1921. This was obtained by a canvass of each individual pumping plant in which data on its discharge and period of operation wei'c obtained as detinitely as the variable tield conditions would permit. This includes the draft by the Terra Bella District. The draft of the Terra Bella District increased from 5816 acres in 1921 to 6843 acre-feet in 1925. The draft by individual plants in 1925 is estimated to have increased to about 85,000 acre-feet. The estimated draft in 1921 was over twice tlie run-otf for that year and over 50 per cent in excess of the estimated mean annual run-off available for these areas. In 1925 the draft liad increased to twice the mean annual run-off. Hydrographs of typical wells are shown in Fig. 19. Well V-3 is at the western end of the area and remote from pumping draft. Little effect of draft or of variations in replenishment is shown. AVell \V_14 at Earlimart is of similar depth. It reflects the heavy pumping draft in this area. Lowei-ing in each year occurred amounting to a total of 17 feet for the five-year period. Well X-36 is near the course of Deer Creek in the center of the area between the area of pumping l\v the Terra Bella Irrigation District and the area between Earlimart and Pixley. A steady lowering is shown which has not varied mate- rially with the run-off of the different years. Well Y-22 is located north of Deer Creek adjacent to the pumping area near the edge of the valley. Continued lowering is shoW'U. Well X-1 is adjacent to the valley wells of the Terra Bella Irri- gation District. The eff'eet of the summer draft and winter recovery is shown. About 20 feet lowering has occurred in the five-year period. AVell X-10 is shown 3 miles we.st of the Terra Bella District wells, l^owering is shown without the marked seasonal fluctuations shown by WelfX-l. Well Y-32 is within the Terra Bella Irrigation District. The water supply for this district is secured from outside sources. A rise of 16 feet has occurred in the five-year period. As there is very little l)umping wafhin the district, this rise reflects the ground water received from the irrigation by outside supplies and the local run-off. Wells at the western edge of the Terra Bella District have not shown a similar rise. The largest lowering has occin-recl along Deer Creek in the vicinity of the ])umping by the Terra Bella District as shown on Map No. 3, amounting to as nuich as 20 feet for the five-year period in parts of this area. A total lowering of about 20 feet has also occurred in the area extending from I^arlimart to Pixley. Wells east of the vrest line oF range 27 east showed an average low- ering of only 0.6 foot in 1925. Some wells along Deer Creek rose. In range 26 east an average lowering of 3.2 feet occurred. In the western part of the area in ranges 24 and 25 east the lowering average 3.1 feet. At tlie western edge of the area where ])umping draft is light and the mingled ground water of the valley trough is approached only very small lowering occurred. Tile i-ecords in tliis area, similarly to those for other areas without lai-ge sources of local water supply, illustrate the sensitiveness of the 110 Department of Public WorJts. iiioimd water lo i)unii)in,u. In the portions oT the area in which there is litth' piunping, only limited lowerinii has occurred even duj-ing the hist five years of deficient raiiifall. Heavy lowering has occurred in all areas of heavy puiu])ing. Tiie lowering; is due to such draft rather tlian to deticieneies in run-off. A continuation of such lowering can ('uly ])e expected if the present rate of draft is maintained. Lowering is to be expected in some parts of the area even in years of excess run-oft'. J*reseiit development represents only about one-fifth of the gross area and results in an ovei'draft on the available ground water su])ply. The attempt to irrigate additional areas of the 85,000 acres in this area not now developed can only increase the rate of ground water lowering and decrease the time until pumping may no longer i)e profitable. Any increase in i>umping from the local sources of ground water is against the interests of those now using such sources in this area. GROUND WATER IN WHITE CREEK AREA. This area extends from the Deer Creek area on the north to the Jvern County line on the south. The w'estern boundary has been taken at about Ihe line of the Santa Fe Railroad. The boundaries do not represent definite divisions between sources of supply. The area rep- resents the apparent general limits within which recharge of the ground water from White Creek may occur based on the ground w'ater contours as shown on Map No. 1. Further west the ground water blends into the mingled sources of ground water supply of the general v;dley trough. Wells of good \ield are seeured in nearly all parts of this area. The (!ei)th of the ground water increases toward the upper or eastern side (if the area. Irrigation wells in the main j^ortion of the area were lormei'ly about 200 feet in depth. Present practice is to install wells of about twice this depth in order to secure larger rates of discharge. As discussed in the following i)agcs, such greater depths of wells do not make available any new sources of ground water supply but merely add to the area adjacent to the well through which the .same .sources of supply may be secured at a more rapid rate. The total mean annual run-off of \Vhite Creek ha.s been previously estimated as 6800 acre-feet. This occurs irregularly and varies in different years from an almost negligible ajnount to several times the average. The run-off has been l)elow normal in recent years. The largei' part of the run-off appears to be absorl)ed in the upper channel which has been cut through the older sediments and may be one of the sources of the artesian supplies of the lower valley area. Surface run-off in recent years has reacluHl the valley area only in limited amounts. In li)26 heavy local storms i)roduced a temporary run-off that exceeded that occurring in any of the other years covered by the olxservations of ground water. Ground ^Vater liesources. Southern San Joaquin Valley. Ill 'I'lie gross area is 104,000 acres. The acreage irrigated is available for 1921, 1924 and 1925. Oronnd water flnctuations are available for the last tivt' xcars. The results jii'e as follows: Mean 1! a in fall Period Area loivering of at Portcrvillr, Per cent of November 1 to Irriaatrd. i/ronvd u-ater percent f/ross ai-ea November 1 acres in feet of normal irrigated 1920-21 -- 11,575 1.3 95 11 1921-22 ■ 1.1 1:5;; 1922-:;4* 15,9.50 5.9 6S 15 1924-25 19,700 3.7 120 19 Total for 5 years 12.0 * Crop area for 1924. Total lowering for 2-year period and average annual rainfall are used. The irrigated area increased 70 per cent from 1921 to 1925. In 1925 the area was 25 per cent larger than in 1924, due mainly to the plant- ing of cotton. The lowering of the ground water in the different years has varied with the amount of use rather than with the rainfall. In 1925 with a larger rainfall, the average lowering was about three times that in 1921. The lowering in the years 1923 and 1924, includ- ing the very dry year of 1924, was less per year than that in 1925. The available data indicate an average gross pumping draft of nearly 3 acre-feet per year per acre of crop. Based on comparisons \\\t\\ other areas a net draft of about 2 acre-feet per acre would be expected, although it is doubtful if pumping has been practiced on much of the area long enough to result in the downward movement of excess moisture reaching the ground water. The draft on the ground water was estimated as 27,000 acre-feet in 1921. The total draft for the five-year period, 1921 to 1925, has probably been about 175,000 acre-feet. The total run-off of White Creek for the same period has probably not exceeded 20,000 acre-feet. The remaining draft could be supplied from the lowering of the ground water over the gross area that has occurred with a drainage factor of 12.5 per cent. This is about the value of the drainage factor found for the similar Shaffer, Wasco and McFarland area and indi- cates that nearly all of the puin]>ing draft has been supplied by ground water lowering within the area rathei' than by replenishment from outside sources. The deficiency in the run-oft' of White Creek during this period amounts to less than 10 per cent of this draft. The pumping draft in 1925 was nearly 50,000 acre-feet, the esti- mated mean annual run-oft' of White Creek is al)Out one-eighth of this amount. With only one-fifth of the area under irrigation giving a draft eight times the estimated available supply, it is not difficult to forecast the future course of the ground water in this area if the present rate of draft is maintained. The preceding discussion has been based on average fluctuations for the whole area. The pumping development is not evenly distributed. The main irrigated area extends eastward from the line between D(>Ian() and Earlimart. The lowering here has been mnch larger than the average as shown on Map No. 3. To the west the lowering has 112 Department of Public Woy^l-s. WELL KERN-32. Shallow well northwest of Delano. 15 20 25 30 192 :i ♦ — 1 1920 *— — 192 • 6 1925 1924 WELL KERN- 13. Five miles east of Delano. 145 150 155 160 o (0 r 3 IKh C 170 3 O Ol 175 E o •^ t- V IS 15 5 ?0 o 4-« c 25 a ®-^ 1 — 1 1 ; »2/ ~" -•-. — o A 195 4 4 N \ ♦-^ 1925 ♦ WELL W-27. West of main pumping area. — 4-^— ~0 — 19 I9'20_ — 192 • 6 — 1 1924 i 55 60 65 70 75 80 WELL W-30. In pumping area 3 miles east of Earlimart ^: ^ ^ , l9?n ^i N \ n; 921 -♦'• _^.* ^ • — " - ,19i 6 ^ ?s • »■ 92a '•> \ ^4 ^ ■^ z OB oc a: > < uj < a. < -> u. 5 •< 5 2 -1 O 3 2 ^ -> -' < I- > o O O "J O 2 Q WELL X-21. Near White Creek and east of pumping area. 80 85 90 95 100 105 110 — ♦- —15?^ 1921 — — 0- — . — 1922 1924 * ♦,^ ^ ♦■V ♦ ^ N s^925 ,^^ 120 125 175 180 185 190 195 90 95 100 WELL Z-1. Three miles west of Ducor in area without pumping. ♦ - - , .I9p ... 1921 1922r \ )26 — — ♦• E:;rr^ ""T^ l^k ■ 1 \ WELL Z-5. Abandoned oil well at eastern edge ol valley. •*^ ^^ IS ^ ^ ^ -• 1922 1924 WELL X-33. Five miles east of Earlimart above main pumping area. 1926 l^S ♦; < a. < 5 < 2 Z J O o- >- > O D 3 3 W O O U ., -> < (0 O z o LEGEND. 1924— a ■ 1925 -♦• 1926 - FIG. 20. Hydrographs of typical wells in White Creek Area. Ground Water Resources, Southern San Joaquin Valley. 113 been iiiucli less. East of the main i)umping area in township 24 south, range 27 east, the area irrigfatcd is more scattered and tlie lowering, whihi greater tliaii tliat west ol' tlic main area, is less than that in the more; heavily pnmix'tl portion. Ilydrographs of typieal wells are shown in Fig. 20. Well W-27 is west of the ])umping area. Tjowering has oeeiirred in all years, although the amount is much less tlian that to the east in tlie pumping area as shown hy Well AV-30. AVell W-27 shows little fluetuation during eaeh season. A gradual hiii continuous lowering has occurred in each year. Well W-80 shows the effect of the heavy local draft •'luring tlie summer with the recovery during the winter season. The lowering in all years has exceeded the recovery; the net lowering has averaged over 3 feet per year. The recovery shown begins as soon as pumping is reduced in the fall and represents ground water adjust- ments between the areas heavily i)umped and those of lighter draft rather than any outside source of supply. This is shown by well X-21, which is 2 miles further east and along the course of White Creek. Well X-21 continued to drop in 1920 and ]921 after Well W-30 had begun to rise. Well X-21 showed recovery in the latter ]>art of 1925. This followed iaiger lowering during the early part of 1925 and reflects the increase in pumjiing near Well X-21 between 1921 and 1925. Well Z-1 is located in an area of very little draft. It shows similar fluctuations to Well W-27 west of the area of pumping. A slow but r-ontinuous lowering occurred in Well Z-1. These four wells illus- trate the dift'erence in fluctuations due to pumping draft. Wells AV-27 and Z-1 outside of pumping areas have lowered less than 10 feet from 1920 to 1925. Wells W-30 and X-21 within or near pump- ing areas have lowered Iti to 26 feet. The lowering in wells ¥7-27 and Z-1 is probably largely due to the pumping rather than the deficient run-oft' of tliese years, as they showed about the same amount of lowering in the very dry year of 1924 as in the other seasons. These comparisons indicate that the lowering that' has occurred is the result of iMimping rather than of the less than normal rainfall for 111 is period. Well Z-5 is an abandoned oil well in section 34, township 24 south, range 27 east. It is deeper than the irrigation wells but shows similar lowering. Well X-33 was drilled for irrigation in 1920, water stand- ing at 80 feet. It has not been used, but a lowering of 17 feet has occurred. This well is to the east of the main pumping area adjacent to Earliiiuirt. There has been discussion in tliis area as to whether the irrigation ^v•ells 400 to 500 feet deep would show the same character of fluctua- tion as the shallow wells. Wells W-27, AV-30, X-21 and Z-1 are not as deep as the irrigation wells now being more generally used. Wells Z-5 and X-33 represent deeper wells. Another well, X-46, in section 30, township 24 south, range 26 east, 1200 feet deep, had water at a depth of 112 feet when drilled in April, 1925. The water stood at a depth of 124 feet in Fel)ruary, 1926, the plant being idle at the time of reading. 8—47076 114 Deparimeni of Public Works. In BulU'tin .), prepared in 1!)L*-I. the rollowing statement was made: "The conditions existing- in this area should make it obvious that only limited pum|)intr drafts can l)e made without serious lowering of the grouml water. The distance from any dependable source of recharge and the .sensitiveness of the ground water to draft as shown by the 1021 records, nmke it evident that pumping in this area is drawing mainly on reserve of ground water which has lieen accumu- lated over an indefinitely long period. When once depleted by pump- ing, a similarly long i)eriod will be required for the refilling of the gi-Gund water storage. A continuation of the present rate of draft can only be expected to result in the lowering of the ground water to depths from which pumping -will no longer be profitable. Every etf'ort should be made to discourage additional development in this area, as it can only lessen the i)eriod of time before this condition occurs." The additional records that have become available since the above quotation was written have served to emphasi/e the statements made. Move favorable seasons of rainfall can not be expected to result in any material change in the rate of lowering. A continuation of the present rate of draft can only result in a continuation of the ground water lowering. If the present extent of development has resulted in the conditions described, any increase in development can only shorten the time when the extent of lowering will so increase the resulting pumping lift that pumping will not be profitable. The interests of those now pumping will be best served by discouraging additional development and l)y limiting the draft to the amounts of water required under careful practice. Ground Wafer h'rsoiirres, SokUk ru Sa)i Joaquin Valley. 115 ClIAl'TEK V. GROUND WATER IN KERN COUNTY AREAS. Ground water conditions in arcjis fuljacenl to Kern liiVer were dis- cnssed in Bulletin 9 of the State Department of Enjjrineerino- based on investiijations made durino- 1920. Ground water observa- tions have also bi^en made l)y the Kern County Land Company and sinee its organization by tlie Kern River Water Storage District. These records are fairly complete for the period 1920 to date. Less extensive records have also been furnished by other owners. The availability of this material has enabled a much more complete analysis of the yround water conditions in this area to be made than would have otherwise been possible within the limitations of time available in the preparation of this report. The great assi.stance received from all of these agencies is gratefvdly acknowledged. Rates of Pumping Draft. In 1920 and in 192Jr-25 the area irrigated l)y [jumping and the amount of draft were secured by a canvass of all i)umping plants. The pumping draft was secured by direct measurement where feasible, by power consumjition. lift and estimated or measured efficiency, or ba.sed on general data. The residting estimates are considered to be fjurly representative of the actual draft and to exceed the draft rather than the reverse. F'or the Shaffer, Wasco and ^IcFarland areas, the 1920 results gave an estimated average draft of 3.3 acre-feet per acre. The correspond- ing figure foi' 1!)25 was 4.0 acre-feet per acre. In 1920 an average draft of 3.0 acri^-feet was found for lands al)ove tiie Kast Side Canal. Ill l!)2r) the draft under th(> Kast Side Canal is reported as 3.7 acre- feet per acre. Both of these results are in excess of the water require- ments of similar crops as determined from canal practice and mate- rially exceed the consumptive use found under similar conditions in other areas. While the figures may be somewhat liberal, it is thought that ajiproximately these amounts were actually pumped. These figures, as well as those in other areas, indicate the relatively heavy rate of pumping usually practiced where ground water is avail- able at any time its use is desired. These results do not mean that all of the water used is utilized by the crops as losses occur under pump irrigation similar to those under canal practice. Seepage from farm canals occurs. With i)umpitig plants on each farni the length of conveyance is relatively small l)nt the rate of loss may be large due to the small stream. Material losses may occur from earth reservoirs. 'J'he percolation losses from the field applications are also large where heavy ii-rigations are api)lied. The estimated draft given is considered to be representative of the water i-emoved from the ground but is not regarded as representative of the actual gi'ound water depletion. Such permanent depletion will be represented t)y the plant transpiration and the evaporaiion only, which for the conditions prevailing in these areas will be much less than the figures given for gross draft. The amounts of the con- 116 Department of Public Works. sninptive use as indicated by records for areas where the available data permits of its separate determination are discussed elsewhere. The gross draft may also be the net draft in the earlier years of pumping until the downward movement of moisture losses has become sufficient in amount to reach and join the ground water. When this has occured, pumping in excess of moisture use by transpiration and evaporation represents merely a circulation of ground water rather than a consumption. In 1920 a total area of 58,250 acres was served by pumping plants in Kern County. In 1925, this had increased to 100.000 acres, or an increase of over 50 per cent in five years. The largest increase in the area served by pumping occurred in the Shafter, Wasco and McFar- land area and southeast of Bakersfield, both above and below the East Side Canal. The United Stat&s CensiLS of 1910 reports 6387 acres as supplied by pumps or flowing wells in Kern County. The report of the Cali- fornia Conservation Commission for 1912 gives 12.240 acres supplied 1)3^ ground water. The area in 1920 was nearly five times that in 1912. The observations of the effects of this rapidly increasing draft on the ground water enable the limitations of the ground water supply to be discussed with more detail than would be possible with less development. As in other general valley areas such discussion can be more conveniently arranged by subdivision of the area into smallar parts. The ground water contours for the entire area are shown on INIap No. 1. These show the direction of slope of the ground water. Ground water movement occurs mainly at right angles to the ground water contours. IMap No. 2 shows the depths to ground water. These repre- sent the ground water without drawdown while pumping. The actual pumping lift will exceed the depths shown on ^lap No. 2 by the amount of the drawdown. The amount of the drawdown varies with the coarseness of the materials and the rate of draft. In most parts of this area good discharges are secured with a drawdown not exceed- ing about 20 feet. In some areas drawdown of twice this amount may occur under large draft. >\lap No. 3 shows the amount of low- ering of the ground water that has occurred from 1920 to 1925. GROUND WATER IN AREA ABOVE THE EAST SIDE CANAL. This area includes all land above the area covered by the East Side Canal area. It includes all development from Edison to Arvin and Rock Pile. Ground water is the only source of water supply. Caliente Creek is the only stream of consequence tributary to this area. In Bulletin 9, based on data available in 1920, the mean annual run-off of Caliente Creek was estimated to be 35,000 acre-feet. No additional measurements have been made since 1920. Comparison v/ith other streams does not furnish any basis for changing the previ- ous estimate. Kern River flows north of this area, a ridge of Tertiar\^ material, usually referred to locally as Kern ]\lesa. occupying the intervening Ground Water Resources, Southern San Joaquin Valley. 117 area. The river is from 100 to 200 feet higher than the ground water south of the mesa. Even with this difference in elevation there is nothing in any data available to indicate ground water movement througli the mesa. The records on Kern River indicate a gain rather than a loss in its channel above First Point of Measurement. The gi-ound water south of the mesa has very little slope to the south as it would be expected to luive if a material supply came from the nortli. Some movement may occur around the point of the mesa at Bakers- field into the northern })art of this area, but such movement is proba- bly small in amount. Well 5-G-17, Fig. 21, in the mesa shows no response to either river or canal conditions. Wells in this area vary from 100 to 600 feet deep. The wells serving larger areas are usually from 800 to 600 feet deep, deep-well turbine pumps being used. Water-bearing material of coarse texture resulting in wells of large yield is generally found in the main developed area in township 31 south, range 29 east. Wells in the southern portion of this area need to be deeper in order to secure similar yields. Owing to the coarse- ness of the material, relatively small drawdown occurs while pump- ing even with large discharges. Analyses of water made in 1920 show good quality in the wells in the main pumping area near Arvin. The quality of water from wells along the mesa at the north end of the area varies with the depth of the well. The surface water strata contain sodium sulphate and gypsum. Wells perforated only in the second and tliird strata show a much smaller amount of these salts. The general ground water in this area had little slope prior to extensive pumping. There Avas a total fall of about 5 feet from the east toward the west in 1920. This indicates a relatively free move- ment of ground water within the area, a condition which is also shown by the material encountered in drilling and the large discharges secured from wells Avith relatively small drawdown. Hydrographs of typical wells are shown in Fig. 21. Well 6-H-3 is located at the north of the larger area of pumping. The well was drilled to a depth of 278 feet in 1912, water standing at 212 feet. This has lowered to 216 feet in 1920 and 231 feet in 1925. The lowering in recent years has been steady with little rapid fluctuation due to either draft or recharge. AVell 7-II-1, 320 feet deep, is within the heavily pumped area and illustrates the difficulty in securing records free from the local effect of i)umping. A 13-foot lowering from 1920 to 1925 is shown. Well 7-11-9 is a shallow well just beyond the end of the East Side Canal. Little fluctuation except a steady lowering is shown. There is not much pumping near this well. Well 7-1-1 is near the east side of the area and above the main pumping area. Lowering of nearly 20 feet from 1920 to 1925 is shown. Well 7-1-3 is nearer the pumping area. This well was not observed prior to 1924. Steady lowering is shown. LIS c 3 O 1. a. Drpartmcvf of PiihJic Works. WELL 7-H-l. Near center ol area. 30 34 38 238 240 245 260 255 260 115 120 125 215 220 225 230 235 WELL 7-H-9. I\lea.- end of East Side CanaL -1925- — ■ >a— M 1924 =a=:— 192^ '^ =^= ^ ' — ^^ .» — - WELL 7-1-1. Above and east of main pumping area. "^ t — ~\ •^ 1920 ,.t^ ,y ■>•■ »~ ► . 1925 ^ ~1924" -•a—™ -a ■^— 1926 — ■♦— -— "♦-- -♦ WELL 7-1-3. Near pumping area. -— ~~ — ■♦ "" "^1 J925^ a. ,1924 — i— ■* -ft—— — &— ^ 1926 ' WELL 6-H-3. Nortti of main pumping area. -• !♦■ 1926 X 1925 X: ^=M /- 1924 165 i_r 170 WELL 5-6-17. In Kern River mesa. ^^ 1926 ♦— — H T -1924- » ) 1925 ' .♦ .. JAN. FEB. MAR. APR. MAY JuN. JUL. AUG. SEP. OCT. NOV. DEC. LEGEND. 1924 — -a- a — 1926^ — ■ FIG. 21. Hydrographs of typical wells In the area above the East Side Canal. Ground ^y(l^(r lu sources, Fiouilurn Smi Joaquin Valley. \V^ Tlie 11)25 crop census for the area aliovc tlic East Side Canal gave the following results: Crop Total acres Per cent of total area Cotton -- 6,993 40 Field crops 543 3 Alfalfa 480 3 Orchard 2,950 17 (Jrapes ___-- 5,863 34 Garden 439 2 Melons 44 Miscellaneous -- 125 1 Totals 17,437 100 This includes all area above the eanal. Four-tifths of the area irri- gated is south of the center line of township 30 south. The gross area above the East Side Canal extending around the edge of the adjacent hill areas to the south line of township 31 south is about 55,000 acres. Present development represents about one-third of this gross area. The total pumping draft for these lands was not secured in 1925. Data secured in 1920 indicated an average draft of 2.8 acre-feet per acre. Some incomplete data in 1925 indicate that the present gross draft is fully as large i)er acre as in 1920. The rate of pumping is sufficiently large in many instances to exceed the crop consumption and downward moisture loss will occur. Similar rates of application under canals have always resulted in additions of the ground water usually accompanied by a rise of the water table. As the ground water is relatively deep under most of this area and overlaid by dry materials, the length of time water has been used on some lands may not have been sufficient to result in the downward moisture movement reaching the ground water, but for permanent conditions the actual draft on the ground water will be represented by the net crop use rather than ])y the gross amounts pumped. The larger part of the flow of Caliente Creek sinks in its channel before reaching the valley areas. Well 6-1-8 is ad.jacent to the course of Caliente Creek as it enters this ai-ea. Water stands at a depth of about 125 feet in this well. A dug well over 50 feet deep in the creek bottom near Bena has not had water in it in recent years. In the latter part of April and in May, 1926, unusually heavy local storms occurred in the foothill areas adjacent to Bakersfield. One of these occurred on the lower drainage area of Caliente Creek and resulted in a larger flood run-oflP of short duration than has occurred in recent years. The well records for tliis period were examined to determine tiie effect, if any, of this run-off on the ground water. The wells were read about April 23 and May 23 in 1926. The change during this period in 1926 was compared with the change between similar dates in previous years. For ten wells situated adjacent to and in the direction of movement from Caliente Creek the ground water averaged to hold its elevation in 1926 where in other years an average lowering of 0.4 foot occurred. Some of this difference is due to decreased draft resulting from tlie decrease in pumping following the rains. The area att'ected did not exceed 20,000 acres. The total difference would not represent over 2000 acre-feet of water. Well 6-1-3 adjacent to Caliente Creek showed no change during this period. These I'csulls illustrate the small aiiuiunt of actual run-off produced 120 Department of Public Works. by suddoii heavy storms of limited area even thoiigli the temporary nin-oti:' may be rapid. Owing to the rapid development that has occurred in this area since 1920. many of the wells observed in 1920 are in use for pumping or not available for direct observation for various reasons so that direct (^omi)arisons are not as readily made. However, the ground water r-ontours in 1920 can be compared with those for 1925. This has been done on ]\Iap No. 3, which shows the lowering that has occurred in the last five years. Direct observations are available for the lowering in 1925. The lowering averaged about 3 feet over the gross area of 50,000 acres. This is eciuivalent to a ground water depletion of about 30,000 acre-feet of water. The run-otie of Caliente Creek in 1924-25 was not measured, but judged by comparison with other streams, Would have been about 10 per cent of normal, or about 14,000 acre- feet. This indicates a total supply used of about 44,000 acre-feet or about 2.5 acre-feet per acre. This appears high and is larger than the probable crop consumption. It is considered to be due to the fact that downward moisture penetration from tlie newly devel- oped and heavily irrigated areas lias not yet reached the ground water. The comparison of tlie contours for 1920 and 1925 shows a maxi- mum lowering of about 20 feet for the five-year period. The maxi- mum depletion occurred in the area of heaviest pumping near Arvin. A lowering of 15 feet occurred in the area of larger development in township 31 south. A lowering of between 10 and 15 feet oecurred between this area and Edison. Against the edge of the mesa the lowering varied from 15 feet near Edison to 25 feet nearer Bakersfield. These changes have resulted in a reversal of the ground water slope since 1920. Instead of a slight slope from the upper eastern edge of the area to the East Side Canal, a cone of depression now exists under the heavily pumped area in township 31 south Avith the ground water sloping into this area from all sides. The run-off during recent years has been below normal and the low- ering of the ground water that has occurred may be due to deficiency in supply as well as to the rate of draft. The present acreage wnth a net crop use of 2 acre-feet per acre would result in a total net draft about equal to the estimated mean annual run-off of Caliente Creek. Some outward movement of ground water into the area under the East Side Canal probably occurs so that unless this can be intercepted by the pumping above the eanal, not all of the run-off of Caliente Creek will be available. The estimated im^an annual run-off of Caliente Creek is based on incomplete data and may be larger tlian the actual .supply. As the deeper wells under the East Side Canal appear to be only indirectly affected by use under the canal little movement of ground water into the area above the canal is to be expected even with additional lowering and increased ground water slope from the East Side Canal into the area of heavy pumping. Present development in this area appears to be fully as large as the available water supply can sui)port. An increase in the draft would be expected to result in a continued lowering of the ground water even in years of average run-off. The high lifts now required in this area will reduce the amount of further lowering than can occur with- Ground Water Resources, Soufhern San Joaquin Valley. 121 nut resultini? in excessive costs. It is considered that present draft is more liable to be in excess of the supply than the reverse and lowering over a period of average years would probably occur even with the present rate of draft. As only one-third of the fi'ross area is now irrifiated, the development of any large part of the remaining area can only be expected to result in a more rapid lowering of the ground water. GROUND WATER IN EAST SIDE CANAL AREA. Ground water conditions in tlie general area southeast of Bakers- field dit¥er above and below the East Side Canal due to the effect of the canal. The East Side Canal area as here discussed consists of the land adjacent to the East Side Canal. It extends about 1 mile to the oast above the canal and to the alkali area west of the canal. This area agrees with that used by the Kern River Water Storage Distmct in its analyses and has been adopted in order that their summaries could be used without recomputation. The irrigated lands depend in some cases entirely on canal service and in others entirely on pumping with much land using both sources of supply. The water supply of this area consists of the delivery to the East Side Canal plus any ground water movement from Caliente Creek or Kern River sources. Ground water derived from Caliente Creek would reach this area, particularly the lower strata, unless intercepted l)y higher pumping. Little if any movement from Kern River would be expected. A small amount of such movement might occur around the point of the mesa at the north end, the ground water depression in the alkali area between the East Side and Kern Island Canal areas, as shown on Map No. 1, indicates that movement from the west into the East Side Canal area does not occur. Outward ground water movement from the area probably occurs into the area of high ground water to the west. Loss by evaporation from the area to the west is indicated by the shallow depth to ground water and the alkali character of the land. Hydrographs of typical wells are shown in Pig. 22. Well 6-H-5 is representative of the deeper wells and shows the lowering during the pumping season and rcovery during the winter. Well 6-H-7 is typical of shallow wells atfected by flow in the East Side Canal. The <:round water in this well is highest in the summer and lowest in the Avinter. oi- tlie reverse of the deeper wells. The largest lowering of the ground water since 1921 has occurred at the nortli end of the area. Larger lowerings have also occurred in the area along and above the canal than in the area below the canal as shown on Map No. 3. In some areas below the canal an actual rise has occurred. The data covering areas irrigated, canal deliver}- and ground water supply are given in the following table. The areas served by canals are taken from the Cannl Company's record for each year: the areas served li\- luimping were secured in 1919, 1920 and 1925, the remain- ing years being interpolated. The canal supply is the gross delivery into the East Side Canal. The -ground water fluctuations are from October of each year and are available only since 1920. The average 122 Department of Piihlic Works. trround water fluctuations include the results from both deep and shallow wells. The service under the East Side Canal is secured under water rights of early priority and does not vary widely with the total flow in Kern Kivcr. The supply per acre of canal service only has averaged 4.3 acre-feet per acre per year for the last seven years and fell below 4.0 acre-feet per acre only in 1924, when 2.8 acre-feet per acre were WELL 6-H-5. Deep well under East Side Canal. « u IS in ■o c 3 o i o a. V O 15 20 25 WELL 6-H-7. Shallow well under East Side Canal. 1926 1925 1920 .-ii: J 924 JAN. FEB. MAR. APR. MAY JUN JUL. AUG. SEP. OCT. NOV. DEC. 1920 — -*- 1924 — />• LEGEND. -♦— 1925 -A- 1926' FIG. 22. Hydrographs of typical wells under East Side Canal. received. These figures include canal losses as well as delivery to the land : conveyance losses have been from 25 to 40 per cent of the total supply. The area served entirely by pumps under the canal has been increas- ing, having more than doubled since 1919. In 1919 the pumping area was about one-half that usually served by canals; in 1925 the pump area exceeded the canal area. This relative increase of the pumped area in proportion to the canal served area probably is the main cause (irdtiiul Water h'rsoKrccs, Soidlnrii Sail Joaquin Valley. 123 I'oi- the .mvatrr liround wattT lown-in^- in 1M25. A similar rate of increase has oeeurred in the punipin the total pumping area that may be partially Records of Use of Water and Ground Water Fluctuations Under East Side Canal. Averle on much of the area near the river. Such pumping in addition to furnishing relief as drainage would also make available a-. _• ^ -~^ 1 — ' » -- 1924 1 V u u ID "t 3 10 C E o a « 8 10 12 WELL 7-F-24. Under Farmers CanaL 1926 ■St y V 1925 ^K 1924 WELL 7-G-IO. Southeast of Bakersfield. <«r^ -t:5* H h ^^ . T 1926 / ^\ If' ^4 r^^^ 19J20 WELL 6-F-9. At Panama. % •^ Fr«- 1^ -* — 4 r^ tN Is 19 25 ^ 2 ""I 1 \'^:. ,-^ 20)ocir>;z-ioa-t->o -z-iOa.i->o -> u. 5<5-)-><«OZO LEGEND. 1920 1924 1925 • — 1926 FIG. 23. Hydrographs of typical shallow wells in main area south of Kern River. to 100 feet in depth. Discharges as large as 3 seeond-feet are secured. Near Rio Bravo, the wells average somewhat deeper with discharges of from 1 to ;} second-feet. The depth to ground water is relatively small as shown on Map No. 2. I Ground Water Resources, Southern San Joaquin Valley. 127 Hy(li-oo;rai)hs of typical wells arc siiowii in Fig. 24. Well 5-F-24 is near the river at the head of the Calloway Canal. Quick response WELL 5-F-24. Near Kern River and Calloway Canal. (I T3 C 3 O WELL J. West of Rosedale in irrigated area. WELL 5-E-31. Four miles west of Rosedgle outside of irrigated area. JAN FEB. MAR. 1919 -=■ 1920 -^ 1921 1922 --■ APR. MAY JUN. LEGEND. JUL AUG. SEP. OCT. NOV. DEC. 1923 1924 1925 1926 FIG. 24. Hydrographs of typical wells in the Rosedale Area. to flow ill the river and canal is shown. Nearly ;ill of the lowering? in 1924 was recovered in 1925. The Huctuations retlect the extent of the stream How with no indication of any continued lowering. 128 Department of Pithlic Works. Well J is west of Rosedalo within the irrigated area. A ready response to canal service is shown. The lowering in 1924 was not re-covered in 1925. In the earlier ,\-eai-s little tendency toward low- ering is shown. The shortage in sn[)ply in 1924 resnlted in a lowering of about 5 feet; in 1925 the supply nearly maintained the ground water, the lowering being less than 1 foot. From 1920 to 1924 little lowering occurred. Well 5-E-31 is located 4 miles west of Rosedale and outside the area canal irrigated. A continual lowering is shown which has a tendency to increase in amount in recent years due to the smaller canal supply on lands to the east The water supply in the Kosedale area is derived from canal diver- sions and river seepage. The ground water in the oil fields to the east has been lowered so that a cone of depression exists and ground water movement from the east, even if it occurred under natural conditions, would now be intercepted. Kern River loses some water in the por- tion of its channel adjacent to the Rosedale area. It is doubtful if much of such seepage moves into the Rosedale area as ground water at Rosedale prior to the construction of the canals is reported to have been about 50 feet lower than at present. River seepage under natural conditions was not sufficient to raise the ground water at Rosedale to its present elevation, although the ground water slope under the early conditions would have been relatively steep in this direction. While some river seepage into this area may occur i1^ amount is considered to be relatively small. Present ground water conditions are the result of irrigation and are dependent on irrigation for their maintenance. The supply received from irrigation in this area is relatively large and pumping has been less extensively developed than in the areas to the north. The crops irrigated consist of about one-half alfalfa and one-half trees, vines and annual crops. The normal ground water in parts of the area is sufficiently near the surface to have caused damage to the land and to result in some loss of moisture^ in excess of normal crop needs. The records of the areas irrigated, the canal supply received into the area and the resulting fluctuation in the ground water are shown in the following table for each season since 1919. In general the ground water fluctuation varies with the extent of the canal supply per acre of crop. Some variations from a direct relationship occur however, particularly in 192:1. Irrigation and Ground Water Fluctuations in Rosedale Area. Gross Area 43,840 Acres. Canal water Acre-feet Avemae Area irrigated, acres per acre rise or fall From Pumps Total of total in water Year canals only Total acre-feet crop area table, feet 1919 11,225 3,420 14,645 56,784 3.87 1920 15,253 2,607 17,860 77.85:5 4.26 — .30 1921 11,600 3,200 14.800 50,48S 3.81 — .13 1922 15,556 2,600 18,156 98,737 5.43 -fl.56 1923 12,653 3,000 15,653 68,789 4.39 — 0.94 1924 6,080 6,080 — 4.79 1925 7,831 4,000 11,831 35,842 3.03 — 1.28 < J round Water ticsources. Southern San Joaquin Valley. 129 In Pi.u. 25 the Teoords are plotted for the area as a wliole and sei)arately for the area in eaeli of the three townships included. The area in township 29 south, range 25 east, consists of the part of the east half of this township north of Goose Lake Slough. All of town- ship 29 south, ranue 2(5 east, is included except the south row of sections. All of towwship 29 south, range 27 east, north of the river and east of the Lerdo Canal is included. In township 29 south, range 25 east, there is no canal irrigation and little pumping. The results for the different years are less consistent than for the other areas. To some extent there appears to be a secondary effect from the preceding year, the rise in 1923 following the larger supply of 1922, being greater than would have been expected from the supply in 1923 and the lowering in 1925, following the dry year in 1924, being greater than would have been expected from the sujiply in 1925. For the two eastern town.ships, the lowering in 1923 was larger than would have been expected from the results in other years. This is probably, at least partly, due to the higher ground water restilting from the larger diversion in 1922 with a resulting increase in outward ground water movement and local soil evaporation. The ground water at the end of the 1922 season was about 1^ feet higher than in 1920. The larger losses resulting from this condition probably account for the dirt'erenee in results in 1923. Th«^ water supply received in the Rosedale area may be consumed either by crop use or soil evaporation, or may pass outward from the area as ground water movement. The results given in preceding table supply data only on the area of crops and do not give any direct measure of these different items, although their sum is indicated by the amount of the supply received and the resulting ground water fluctuations. If these different items of disposal of the water supply were constant the years covered by the observations would permit a solution for their individual amount. However, the elements are not constant and the rate of variation with other factors is not known. Crop use of moisture may be at least closely proportional to the area froi>ped in different years, but soil evaporation and outward move- ment of ground water vary with the height of the ground water. These elements can only be estimated by assuming values for the crop use and drainage factor and considering that the remaining unaccounted for supply represents the sum of outward ground water movement and excess soil evajioration. This has been done in the ff)llowing table. A crop use of 2.0 acre-feet per acre has been assumed based on gen- eral comparison with other areas. This represents the crop use expected under the local conditions for land free from the effects of high ground watei-, any additional crop due to high ground being considered as a ])art of the excess soil evaporation loss. A drainage factor of 18 per cent has been used. This is based on lesults in other areas. It is a relatively high value which is considered warranted by the conditions in this area where the lowering is \\ithin the surface material which averages fairh^ coarse in texture. 9 — 47076 130 Departmeni of Public Worlcs. The results of these assumptions are as follows : Total water supply Year acre-feet 1!)20 78,000 1921 56,000 1922 99,000 1923 69,000 1924 1925 36,000 Estimated crop use at 2.0 an-c-feet per acn-e. total acre- feet 36,000 30,000 36,000 31,000 12,000 24,000 T. 29 S.. R. 25 E.. M. D. B. & M. +2.0 0.0 -2.0 ^.0 1923 • ^ 1 921^ 1*920 1922 1924 ^ < 1925 'i \ 3 i \ 5 6 Estimated Chan {J c in fjround water ivithin area, total acre-feet — 2,000 — 1,0(10 4-12,000 — 7.000 — SS.OOO —10,000 Resulting unavcoiinted for supply. acre-feet 44,000 ' 27,000 51,000 45,000 26,000 22,000 'J'otal f/rvH'id water change since 1920, feet .0 — 0.1 + 1.4 + 0.5 — 4.3 — 5.6 T. 29 S.. R. 26 E.. M. 0. B. & M. +2.0 0.0 -2.0 ^.0 -6.0 1921. ^r 1925 ^ '<1920 • 1923 •^24 ^ > u •D C P +4.0 ^2.0 0.0 -2.0 -4.0 T. 29 S.. R. 27 E., M. D. B. & M. c ro .c O -6.0 -«.0 19! f /^n D 1925 y 1921 • y / 1923 / / ^1924 +2.0 0.0 -2.0 -4.0 -6.0 ENTIRE AREA. 1 1925 192W r*^1920 1*923 ^ ^ ^ ^1924 Acre feet per FIG. 25. Relation of water applied In irrigation, from both canals and wells, to change in level of ground water in Rosedale Area. Variations in the estimate of consumptive use or drainage factor will affect the resulting estimate of unaccounted for supply. Material changes would be required to change the general nature of the results, however. The resulting unaccounted for supply appears to vary widely. These variations are, however, at least partly, accounted for by the changed conditions in 1924 and 1925, leaving 1921 as the only incon- sistent result. A greater lowering of the ground water m 1921 would have been expected than the lowering that occurred. Ground Water lUsonrces, Southern San Joaquin Valley. 131 The I'c.siilt.s for 192U to l!)2.'i, iueliisi\'c, ruprrsent a i)enod of larger canal supply, hisher ground water and eonseciuently lariicr ground watt'r losses. An unaceounted for suj)ply of about 45.000 acre-feet per year ajipcars to 1)(> indicated by these results. The lack of any canal supply in 1924 resulted in all cro]) use being supplied from the m'ound water. This, with outward ground water nioveinent, resulted in a material lowering. fSuch lowering resulted in the ground water being below the influence of surface evaporation and piobably also reduced the outward moven\ent. The smaller unac- counted for supply may be a measure of the conditions that will occur with such lower ground water. In 1925 the supply was still deficient and the ground water remained lower than in former vears. The unaccounted for supply was less in 1925 than in 1924. The average canal supply received by this area is about 85,000 acre- feet per year. The average area irrigated by canals and pumps may he 20,000 acres. With stable ground water this Avould result in a surpliLs .supply over ci'op needs of about 45,000 acre-feet. Present average conditions in this area w-ould be expected to replace the ground water lowering of 1924 and 1925 and restore tlie previous rate of outflow and excess soil evaporation loss. The present average supply for this area exceeds the present crop demands and an increase in pumping should be feasible without material permanent ground water lowering below the depth sufficient to prevent soil evaporation and reduce outward ground water movement. The lowering of the ground w^ater in 1924 and 1925 resulted in a reduction of about 20,000 acre-feet per year in the indicated losses from the area. Further lowering of the ground water should still further reduce outward inovement. The extent of such reduction with any given amount of lowering can not be predicted, but a lowering within the limits of economical pumping should result in a further reduction in outflow. AVhile the changed conditions resulting from the absence of canal supply in 1924 have not been in effect sufficiently long to enable dependence to be placed on the numerical results indicated, the records presented appear to justify tlie conclusion that a matei-ial reduction in the present delivery to this area could lie nuide without resulting in a shortage in supply, provided the ground water is maintained below the high levels found from 1920 to 1923. GROUND WATER IN SHAFTER, WASCO AND McFARLAND AREA. This area extends from the 7th Standard Parallel south to Ijetween McFarland and Delano on the north and from the Lerdo Canal westward to include the main pumping areas west of Shaffer and Wasco. This area depends mainly on the Lerdo and Calloway canals and on Poso Creek for its ground water replenishment. The western boundary of the area dependent on these sources of supply is not definite. In the lower valley areas to the west, artesian wells have been obtained ; Avells formerly flowing continuously now flow, if at all, only during the winter months, however. On the south, the line of division between the area affected by I'echarge from the Rose- 132 Department of Public Worls. dale area and the area aft'eeted only by use under tlie Calloway canal is similarly indefinite. The areas irrijiated in this area, l)i)1h by canals and by pumping, liave been canvassed at different times. Tlie ground water fluctuations liave also been determined for each season, the seasons ending Septem- ber 15. This date was selected as the lowest point of the ground water c.ycle, a rise nsually oecnrring after this date. These results, inclnding the canal deliveries, are taken from the data compiled by the Kern Kivei- Water Storage District. The canal service in the area south of the 7tli Standard Parallel soutli luis been more dependable than lliat in tlie area north of the parallel. IMore complete canal service has been received south of the ]>arallel and pumping is less extensive. The gronnd water slopes, fluctuations of wells and other records indicate that the ground water south of the parallel has only a limited effect on the supply north of Ihe parallel and the ground Avater in the area north of the parallel is considered to be mainly dependent on the surface water supply enter- ing the area. The sources of surface supply are the Lerdo and lower Calloway canals and Poso Creek. The records of canal supply are given in the following table. The (luantities are those measured at what is known as Second Point Callo- way, where the Calloway Canal enters this area and at the diversion of the Lerdo Canal from the Beardsley Canal. Some delivery from I'alloway Canal above Second Point, which is used in this area, is also included : Total acre feet 30-ycar Canal 19^0 1921 1922 1923 lOZ-'t 1925 mean Calloway Canal, above sec-ond point- 3,100 14,300 19,400 5,400 .i.^OO 10.000 Stronil point 45.000 29,600 78,300 1'6,400 10,400 66.00(1 ivirdu Canal 8,050 11,100 19,600 12,600 4.100 18,200 'lotals 56,150 55,000 117,300 44,400 17.800 94,200 The flow of Poso Creek above its entrance into this area has been measured since 1919 with the following results: Total run-off Year acre-feet 1920 9,270 1921 4,510 1922 __- 7,770 1923 10.050 1924 1925 7,360 The probable mean annual run-off of Poso Creek has been estimated ax 20,000 acre-feet, the years covered by the records were all below normal in precipitation. Early records of ground watei" in this area are fragmentary. Two wells were drilled in 1870 to obtain stock water for use in the con- struction of the Calloway Canal. One well was located in section 27, township 28 south, range 26 east, Avater standing 94 feet from the surface. In 1920 ground water at this location stood 58 feet higher than this elevation. The other well was located in section 2, township 28 south, range 25 east, water standing 105 feet from the surface. In ] 920 ground water at this location stood 51 feet higher than this eleva- (J round W'dftr h'< smircrs, SuutlKrii Soji Joaquin Valley. 133 tion. A third well, near Kosedale, was 59 feet higher in 1920 than in ]87(j. These records indicate that the present ground water in this general area is the result of losses from irrigation rather than from natural sources. The lower hill areas to the east represent tertiary formations. These dip heneath tlic surface till and may extend entii-cly under the area. Such tertiary i'oi-iiiatious are, however, at considerable depth and all pumping now practiced is from the more recent valley fills. Wells in the tertiary formation due to its liner texture would give smaller yields than those in tlie I'cceut alluvium. Conditions of replenishuu^nt j;re also unfavorable in tlie tertiary material, as its outcrop is above the canals and in an area of limited precipitation and consequent small absorption into ground water strata. The following discussion regarding ground water in this area has been based on the conclusion that the only sources of su])i)ly of appre- ciable amount are those received from canal diversions and Poso Creek. The data on the areas irrigated, tlie water supply and the ground water tluetuations for each year since 1919 are sumumrized in the following table. The area irrigated by wells has increased steadily. The water suiiply per acre of total irrigated area has varied widely in tlie different years. Such variations are reflected in the resulting ground water fluctuations. Very little of the pump served area receives any canal service. The ground water fluctuations in this area reflect the composite result of several factors. These include the extent of the ground water supply received, the amount of use by canal served lands, the amount of pumping, and outward ground water movement. The bal- ance between elements of supply and use is secured from or added to the accumulated ground water. The amount of the ground water fluctuation depends on the extent of this balance and the amount of ground material that is drained or fllled in order to supply or store the balance. Summary of Areas Irrigated, Water Supply and Ground Water Fluctuations in Shatter- Wasco-McFarland Area. Wairr sui)i)h/. Ateraf/e (irrr.-lict lOKCriiif) GronN urra, IKi.OOO an-rs per acre of Area irriyatcd. acres Water sup-ply. acre-feet of total fjrouiid From From Poso irriaated iratrr Year canals By wells Total canals creek Total area feet 1919 18,970 .31,000 49.970 50.308 1920 1-1.130 30,8:)() 44,931) r,(i,1.54 9.270 (i."),424 1.45 —1.8 1921 4.291 33.000 37,81)0 55.034 4.510 59.544 1.5S —2.12 1922 17,202 30,500 53,700 117.324 7,770 124.004 2.32 — 0. 1> 1923 9.7:-!7 3;».2i)0 48.940 44,300 10,050 54.410 1.11 —3.10 1924 41,994 41,994 —4.60 1925 4,574 44,800 40,370 17.802 7,300 25,432 .52 —5.24 Notes. — Area.s irrigated by wells determined in 1919, 1920, and 1924 ;ind inter- liolated for f)ther years. Lowering of ground water in 1920 based on records tor less than the full yeai'. The area served by canals varies with tlie water supjily. Irriiiation from canals is now practiced under conditions wliich result in heavy rates of appliealinn on llic hmds .served with consequent large addi- tions to the ground water. Such losses would be reduced with iinpro\('iiients in ]u-esent canal irrigation practice. Of the gross arcvi 134 Depait)nc)it of Public Worls. of 181,000 acres included in tlie area here considered, only about one- eip'hth is normally irriyated from canals. In recent years the actual area so irrijiated lias been less than this amount due to deficiencies in stream tlow. The area now served by pumps is about one-fourth of the Rross area. Outward <>-round water movement from this area may occur. Ground water is olitainable in areas to the west and north toward which the ,-25 1920-25 T. 25 S.. Rs. 24. 23. 26. E. 23,040 ■ — 2.88 ■ — 1.35 — 3. 70 • — 5.7" —4.40 — 18.10 T 26 S., Rs. 24, 2.5. 26 E. 46.080 —2.50 +0.49 — 3.0G — 4.68 —5.95 —15.70 ■1. 27 S.. H-i. 24, 2."), 2ii E. 5U,5iiU —2.12 —0.1:? — 4.0.3 —6.77 —6.38 —19.4:: N. .'. of T. 28 S.. lis. 24, 25, 26, 27 K ;10.9:?0 —1.41 —1.50 — 2.62 —2.97 — 4.24 —12.74 S. .^. 'of T. 28 S., Us. 24, 25, 26, 27 K .30.720 —1.65 —0.84 —1.67 —1.66 —4. 02 — 9.84 Totals 181,330 —2.12 —0.48 —3.10 -4.60 —5.24 —15.54 A\'ater suppiv aore-feet per acre of crop area 1.58 2.32 1.11 0.52 Township 27 south represents the heavily pumped Wasco area and sliows the maximum lowering. The average lowering in township 27 south, range 24 east, whieli includes the main pumping area was 19.5 feet for this period. The lowering to the east in township 27 south, range 25 east, was 25.5 feet. Township 27 south, range 25 east, includes the areas served hy canals and reflects the extent of such service. Ground water rose 2.5 feet in ]922 with large canal supplies but fell 9.9 feet in 1924 with no canal supply. ToAvnship 26 south reflects the effect of canal use in 1922, being the only area that rose in that year. It also receives some benefit from Foso Creek. Township 25 south is further removed from canal irrigation and Poso Creek and shows larger lowering. The preceding discussion furnishes a basis on which to estimate the relation of present use in this area to the average water supply. As the supply received in the last five years has been only 43 per cent of the average the lowering that has occurred does not of itself indi- cate an overdraft on the ground water. The average canal supply has been 94,200 acre-feet per year. The average run-off of Poso Creek has been estimated as 20,000 acre-feet. giving a total average supply of 114,200 acre-feet. The present pumped area is 50.000 acres. In normal years about 18.000 acres are irrigated from canals; the average may be 12,000 acres. If the crop use is 2.0 acre-feet per acre, 124,000 acre-feet would be reciuired for the average crop area. An outflow of 25,000 acre-feet gives a total average demand of 149,000 acre-feet, or 34,800 acre-feet in excess of the average sui)ply. With present development and average water supj)ly conditions a lower- ing of about 1.5 feet per year would be exi)ected. The only year covered by the observations in Avhich an average water supi)ly was received was 1922. With 8300 acres .less of pumping area a lowering of i foot occurred which is in agreement with the above estimate. WelLs in this area are generally le.ss than 200 feet in d(»pth. A few wells of about 500-feet depth are in use and the tendency is toward the use of deeper wells. Lai'ger discharges are usually secured from the deeper wells. There has been some discussion as to whether the deeper wells secure a (lififerent sonrc(^ of supplx' tlian the shallow wells and whether similar fluctuations would be shown. The Hoover farm drilled deeper w<'lls in 3921 and recoi-ds of their fluctuation 'can be compared with those 138 Department of Public Works. WELL 3-D-7. In canal irrigated area. 10 15 20 25 30 35 40 45 50 55 "-^ 1^2? r/ X ^920 .,^^ ♦ •»• ^ + ♦■ -♦- U926 ♦■ ♦ ♦! ♦ ♦ '925 9191/ — fs "*^ fl> 1924 ♦ ♦ ♦ ♦ * ♦ ♦ ♦ ♦ ♦ WELL 4-D-5. Southwest of Stiafter in pump area. c ▼^r" WELL 3-C-6. Soutiiwest of Wasco in pump area. I WELL 2-D-2. Nortti of Wasco. 15 20 25 30 35 — .-_L_._|_i92F \92j:--|5>5^i JAN. FEB. MAR. APR. MAY JUN. JUL. AUG. SEP. OCT. NOV. DEC. LEGEI^D. 1919 — °-- 1920 — ». 1921 o 1922 -^- 1923 • — 1924 -«~- 1925 1926 FIG. 27. Hydrographs of typical wells in Shatter and Wasco Areas. Ground Water Iicsources, Southern San Joaquin Valley. 139 of shallow wells on atljacent areas. These wells are in sections 29 and 30, townshi]) 27 south, range 25 east, l)etween Wasco and Shafter, and at the eastern edge of the heavily pumped area. The depths vary from 405 to 562 feet. ^ Readings on these wells for the date of drilling and also for tlie spring of 1926 have heen furnished by ]\Ir. Harvey Kilburu. superin- tendent of the Hoover farm. The results are as follows : Total loiocrino Well Year installed Years since drilled since drilUny 29-A 1921 5 21.5 29-B 1921 5 25 29-C 1921 5 23 29-D 1921 5 28 29-E 1925 1 1 30-A 1921 5 19 30-D 1925 1 2 Sec. 31-1 1922 4 19 31-2 192.1 3 19 The average lowering on the live w^ells drilled in 1921 w-as 23.3 feet for the tive-year period. In order to compare these results with those of shallow wells, the rec- ords of 8 adjacent wells observed by the Kern River Water Storage Dis- trict were examined. The lowering for the same ])eriod averaged 18 feet. The average lowering in township 27 south, range 25 east, from September. 1920, to September, 1925, was 25.5 feet. These results indi- cate that these deeper wells have shown similar effects to those shown by the shallow wells. The logs of the deeper wells show strata of considerable thickness of clay. I'ercolation of water through such strata Avould occur, if at all relatively slowly. However comparisons of the logs of these wells show no similar or connected clay strata occurring in the different wells. Such clay strata if not continuous would not prevent com- mingling of the water in the upper and lower strata and it is considered that such commingling occurs. If the water secured from the deeper strata is not supplied from the canal delivery and Poso Creek run-off, it would have only a limited replenishment. Other sources of supply would be the absorption in foothill areas to the east, which would be very limited in amount due to the small precipitation received. Deep wells have the advantage of greater percolating area and give more discharge with less draw^down, but it is not considered that they secure any different source of supply than that ol)tainrd from the shallow wells. They may have the further advantage tliat by drawing from deeper strata more of the outward ground water movement may be intercepted for use within the area. The character of the ground water tiuctuations is illustrated by the hydrographs of typical wells in Fig. 27. Well 3-D-7 is within the area receiving canal .sen'ice. The ground water responds rapidly to adjacent irrigation, the rise varying from 25 feet in 1922 with heavy irrigation to zero in 1924 with no iri-igation. No winter rise due to rainfall or ]-un-()rt' in Po.so Creek is shown. Except for the effect of canal irri- gation, the ground water in this well show's a relatively steady lower- ing at the rate of about 10 inches per month. Such lowering would be due to outward gi-ound water movciiKmt toward tlu- pumping area near Wasco. 140 Depart nieni of Public Works. WELL 1-E-1. North of McFarland, east of pump area. 50 r 55 60 ♦ ♦ ♦ ♦ ♦ ♦ ♦ ► ♦• « ♦ ♦ /«a" . . ■ — ■ ^— 1924 1 ■1 1926 ♦ ♦ ♦ ♦ * ♦♦!♦♦♦ ♦ ♦ WELL 1-D-3. Morthwest of McFarland in piimn area. V 45 50 55 60 ♦ ♦ * ♦ ♦ ,19261 *■♦♦ ♦ ♦ ►♦ ♦ J 925 * * * •*- 1924 ^-^ J ^ * * ♦• *♦♦!♦♦ ..*♦** 1 a Q WELL l-C-1. West of McFarland and west of pump area. I JAN. FEB. MAR. APR. MAY JUN. JUL AUG. SEP. OCT. NOV. DEC. LEGEND. 1919 1920 1921 1923 1922 — ' '-.^'' 1926 ■ I FIG. 28. Hydrographs of typical wells in McFarland Area. (iround ^V(^ter Hcsources, Southern San Joaquin Valley. 141 \\\.]\ -l-l)-o is .soiitliwest of S;iiaftor within the puinpinfi; area. The loworingr diirinji' the suimner -with a rise after the end of tlie i)unii)- in{? season is sliowii for all years. A continuous drop from year to year is shown for each year. Tliere is a somewhat larger lowering- in 1!»24 amnH2r). Well .S-C-6 is located southwest of Waseo in the pumping area. Continual lowering is shown f lom year to year. Recovery occurs when pumping decreases during the winter months, but in no year covered by the records has the reeovcry been equal to the lowering. AVell 2-D-2 is located north of Wasco in an area receiving some canal service and adjacent to scattered areas of pumping. A rise occurred in 1020 and 1922, some lowering in 1921 and 1928, and marked lowering in 1921 and 1925. This well is about 2 miles soutli of Poso Creek, but shows no response to flow in upper Poso Creek. Lowering con- tinues., during the Avinter months. Continual movement of gi'ound water through this area is indicated with little increase in the rate of lowering during the summer, due to local pumping. A rise occurs whenever there is adjacent canal irrigation, but such rises are not as marked as in Well 3-D-7 which is nearer to the main canal irrigated areas. Wells 1-P:-1, l-D-3 and 1-C-l, Fig. 28, are in the ^NlcFarland area. Well 1-E-l is north of ^NIcFarland and east of the pumped area. For the period covered by the record a continual and relatively uniform lowering of over 4 feet per yeai- is shown. Well l-D-3 is WTst of ^ifcFarland within the pumped area. A similar continual lowering is shown with the added etfect of summer pumping. Well 1-C-l is to the west and although only 78 feet deep fluctuates widely between the summer lowering and the winter recovery. Less tendency toward continual lowering is shown. The fluctuations of this well are more nearly representative of those of strata under pressure than of surface water. The lack of any canal delivei-y in 1924 furnishes an opportunity to observe the rate at wdiich the the ground water lowered by outflow in the canal area under the Lerdo and Calloway canals. Wells -were selected which were also sufficiently to the east of pumping areas to be unatfeeted directly by such pumping. Ten wells averaged to lower at the rate of 0.65 foot per month in 1924. Of these, 7 wells averaged to lower at the rate of 0.5 foot per month in 1925. The small amount of canal delivery in 1925 together with the lower ground water elevation probably account foi' the reduced rate of lowering in 1925. A rate of lowering of 0.6 foot per month with a 12.5 per cent drainage factor represents a drainage of 0.95 acre-foot per acre per year. This would appear to be aliout the rate of outward movement, to be expected to occui-, from the higher portion of this area. The preceding discussion is considered to support the conclusion that l)um|)ing in this area has increased until the draft exceeds the present average water supply so that continued ground water lowering is to be anticipated ev«m under normal conditions of water sup])ly. It is con- sidered that the main source of ground water supply in this ai-ea i^ the loss from canal use. Such losses are largely due to present con- ditions of use. A decrease in the use of Avater from canals per acre irrigated would rcMliiee the additions to the ground water from such 142 D(i>---r°**-CH MAP 2 DEPTH TO GROUND WATER AS OF OCTOBER 1925 IN SOUTHERN SAN JOAQUIN VALLEY DIVISIONS OF ENGINEERING AND IRRIGATION AND OF WATER RIGHTS s'- E-iC;j ■ --;sir 1} i pt)RTERVIt.LE LEGEND COUNTY BOUNOAHIES ""| " ~l AREA AND DISTRICT BOUNOAR'ES CANALS - BAILHOADS BIVEflS AND SLOUGHS 1--====^ ~ I CONTOURS OF GROUND WATER IN FEET {^'Xx^^ /^l r^. i^ WELLS- I J MAP I GROUND WATER CONTOURS USG.S DATUM AS OF OCTOBER, 1925 SOUTHERN SAN JOAQUIN VALLEY DIVISIONS OF ENGINEERING AND IRRIGATION AND OF WATER RIGHTS SCALE )N MILES USBiav )1 V'^Sd THIS BOOK IS DUE ON THE LAST DATE STAMPED BELOW BOOKS REQUESTED BY ANOTHER BORROWER ARE SUBJECT TO IMMEDIATE RECALL J jr -^ c ! " FI-B20 1988 PHYS SCI LIBRARY JUN 7 1990 PHYS SCI UBRARi; RE@ffitV!H>l9c SEP 1 9 1996 APR 1 3 2000 JAN 1 9 2000 JAN 2 7 2000 REE'il \UG 2 8 2000 'X? RECEIVED ,AU6 2 ii 2000 PSL LIBRARY, UNIVERSITY OF CALIFORNIA, DAVIS Book Slip-Series 458 ■^ ,1 1^ ^. i / 3 1175 00671 2015 PHYSICAL SCIOWIS L1B«AIW TC8E4- Pocket LIBRART UNIVERSITY OF CAUFOENXA DAVIS 111583