THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA DAVIS STATE OF CALIFORNIA DEPARTMENT OF PUBLIC WORKS DIVISION OF ENGINEERING AND IRRIGATION BULLETIN No. 3 Water Resources of Tulare County and Their Utilization 1922 (Based on Investigation in Cooperation With Tulare County) 21044 CALIFORNIA STATE PRINTING OFFICE SACRAMENTO, 1922 STATE OF CALIFORNIA DEPARTMENT OF PUBLIC WORKS SACRAMENTO Division of Engineering and Irrigation A. B. Fletcher, Director, Department of Public Works, August 29, 1922. BUILDING. Subject: Water Resources of Tulare County. Dear Sir : Early in the year 1920 I was approached by a committee from Tulare County which committee was very eager to have assistance in determining something more definite concerning the water supply of the county than then existed. We were, at that time, engaged in the examination of the problems of Kern River which examination has been completed and a report of which is contained in our Bulletin No. 9. The Tulare County committee had knowledge of our work in Kern County and expressed a desire for such service in their county, offering to aid in meeting the necessary expenses. The State Department of Engineering was in great need of such a study in relation to the water supply of the Lindsay-Strathmore and Terra Bella Irrigation Districts. Arrangements were made for the work, Tulare County to supply $7,500 toward the expense, the Count}* Water Users Association $2,500 and the state the remainder. The total cost has been about $22,000. It would have been impossible for us to have secured the information now assembled within the period such work has been done and within the financial means of the Department of Engineering. The value of the work will depend largely upon a generous circulation among Tulare County people. Our division should have it in more permanent form. I herewith submit text of same ready for printer. Yours very truly, W. F. McClure, Chief, Division of Engineering and Irrigation Approved for publication, August 30, 1922. A. B. Fletcher, Director of Public Works. TABLE OF CONTENTS Page INTRODUCTION 9 SUMMARY AND CONCLUSIONS 10 MAIN REPORT 14 Chapter I. GENERAL FEATURES 14 Climate 14 Soils 14 Crops 15 Chapter II. WATER SUPPLY 16 Kaweah River 17 Accuracy of Kaweah River Records 19 Kaweah River Records 1919 and 1920 20 Channel Losses in Kaweah River 23 Tule River 23 Main Tule River 24 South Fork of Tule River 25 Summary for entire Tule River Drainage Area 26 Run-off of Smaller Drainage Basins in Tulare County 26 Deer Creek 27 White Creek _ . 30 Run-off of Minor Drainage Areas in Tulare County 31 Total Water Supply from Drainage Area Discharging into Tulare County 34 Surface Outflow from Valley Areas l\~> Outflow from Kaweah Delta 35 Outflow from the Tule River 39 PART II. UTILIZATION OF THE RUN-OFF OF KAWEAH RIVER. Chapter III. PRESENT UTILIZATION OF THE RUN-OFF OF KAWEAH RIVER 43 Canal Diversions from Kaweah River , 43 Maximum Rate of Diversion by Canals from Kaweah River 49 Areas Irrigated by Kaweah River Ditches 50 Duty of Water under Ditches 53 Total Irrigated Areas Dependent on Kaweah River for their Water Supply.. 54 Sub-irrigated Areas ' 56 Rate of Increase in Area Irrigated by Kaweah River Run-off 57 Chapter IV. USE OF GROUND WATER IN AREA DEPENDENT ON KAWEAH RIVER RUN-OFF 59 Introduction 59 Elements of Inflow or Recharge of Ground Water 60 Estimated Draft on Ground Water 60 Possible Sources of Loss from Kaweah Delta Ground Water Storage 63 Ground Water Conditions along Kings River Ridge 65 Ground Water Fluctuations on Kaweah Delta During Winter Months-- 65 Formation of Kaweah Delta 68 Ground Water Fluctuations (ill Ground Water Fluctuations 1917 to 1921 70 Ground Water Change Since 1905 72 Variations in Conditions of Water Supply and Use in Different Parts of Kaweah Delta 72 Main Area Covered by Canals 74 Lower and Western Part of Kaweah Delta SI Upper Canal Areas $2 Area of Kaweah Delta West of Lindsay-Strathmore Irrigation District S4 DEPARTMENT OF PUBLIC WORKS. Areas Adjacent to Kaweah Delta 85 Areas Along the Foothills North of Kaweah River Areas 85 Cottonwood Creek Area 80 Lewis Creek Area S7 Lakeside Ditch Area 88 Corcoran Irrigation District 89 Chapter V. KAWEAH RIVER STORAGE SITES 90 Available Storage Sites 90 Economical Size of Storage ' 93 Seasonal Use 94 Use of Storage 97 Evaporation Losses 100 Summary of Use Obtainable from Storage 101 Power Development at Dam 102 Storage of Surplus Waters 104 Storage of Winter Flow Only 107 Storage of Flood Flow Only 107 Chapter VI. POSSIBLE CHANGES IN USE OF RUN-OFF OF KAWEAH RIVER 109 PART III. UTILIZATION OF WATER SUPPLY OF SOUTHERN PART OF TULARE COUNTY. Chapter VII. AREA DEPENDENT ON TFLE RIVER FOR ITS WATER SUPPLY 117 General Formations Affecting Ground Water 117 Extent of Tide River Area 118 Areas Irrigated 119 Use by Canals - 120 Use of Ground Water 125 Areas Within Which Some Lands Receive Canal Irrigation 130 Lands East of West Line of Range 27 East 130 Lauds in Range 2G East 130 Lands Along Lower Tule River 130 Tule River Areas Outside of Areas Served by Canals 131 Area on North of Tule Delta 131 Lands East on West Line of Range 2."> East . 134 Lands West of West Line of Range 25 East 134 Lands South of Tule River Canal Area 135 Summary 136 Chapter VIII. STORAGE SITES ON TULE RIVER .- 137 Pleasant Valley Reservoir Site on Main Tule River 138 Storage on South Fork of Tule River 143 Combination of Pleasant Valley and South Fork Storage 145 Chapter IX. OTHER AREAS IN SOUTHERN TULARE COUNTY 147 Deer Creek Area 147 White Creek Area 152 Area in Southwestern Tulare County Whose Ground Water is Considered to Come from Mingled Sources 154 Northern Kern County 155 INDEX OF FIGURES. Figure Page 1 Comparison of Discharge of Kaweah River at Three Rivers and at McKay Point Based on Automatic Registers 20 2 Relation of Precipitation and Elevation for Tulare County Streams 27 3 Relation of Precipitation and Run-off for Tulare County Drainage Areas 28 4 Total Annual Run-off Curves for Small Unmeasured Drainage Areas in Tulare County — 29 5 Relation of Fluctuations of Ground Water in Kaweah Delta to Run-off During the Winter Months 67 Hydrographs of Typical Wells Extending Along the Course of Outside Creek 76 7 Hydrographs of Typical Wells on Lines Radiating Across Kaweah Delta Along Deep and Packwood Creeks 7S 8 Hydrographs of Typical Wells in Northern Part of Kaweah Delta and in Adjacent Areas to the North and West SO 9 Hydrographs of Typical Wells in Upper Kaweah River Areas S3 10 Area and Capacity Curves for Ward Reservoir Site on Kaweah River 91 11 Curves Showing Relation of Estimated Costs to Capacity for Ward Reser- voir Site on Kaweah River 94 12 Relation of Storage Used to Constructed Capacity from Reservoirs on Kaweah River Supporting an Irrigation Draft of 375.000 acre-feet 9S 13 Hydrographs of Typical Wells in Tule River Area 12S 13A Hydrographs of Typical Wells in Area West of Lindsay - Strathmore Irrigation District and Dependent on Tule River for its Ground Water Supply 133 14 Profiles of Dam Sites at Pleasant Valley Reservoir Site on Tule River — 13S 15 Area and Capacity Curves for Pleasant Valley Reservoir Site on Main Tule River 139 16 Estimated Costs of Storage at Pleasant Valley Reservoir Site on Tule River 141 17 Capacity Curve for Reservoir Site on South Fork of Tule River 144 18 Hydrographs of Typical Wells in Southern Part of Tulare County 150 INDEX OF PLATES. Plate I. Fig. Fig. Plate II. Fig. Fig. Plate III. Fig. Fig. Plate IV. Fig. Fig. Plate V. Fig. Fig. Plate VI. Fig. Fig. Plate VII. Fig. Fig. Plate VIII. Fig. Fig. Plate IX. Fig. Fij Page A — Division Weir at McKay Toint 21 B— Gaging Station on Cross Creek at Hanford Road Bridge 22 A — General View of Drainage Area of Yokohl Creek 31 B — Concrete Flume of Lindsay - Strathmore Irrigation District 31 A — Diversion Weir of Tulare Irrigation District 44 B — Gaging Station on Jennings Ditch 44 A — Waste Gate on Lakeside Canal near the Diversion from Cross Creek 53 B. — Pasture Irrigation Under the Lakeside Ditch 53 A — Cross Furrow Irrigation of Orchard near Yisalia 61 B — Pumping Plant and Concrete Fipe Distribution System for Orchard near Exeter 02 A — General View of North End of Dam Site at Ward Reservoir Site on Kaweah River 92 B — Detail View of Character of Rock on North End of Dam Site at Ward Reservoir Site on Kaweah River- 03 A — General View of Ward Reservoir Site on Kaweah River 95 B — South End of Dam Site at Ward Reservoir Site on Kaweah River__ 95 A — Weir at Head of Porter Slough on Tule River 124 B — Diversion Dam of Stockton Ditch on Tule River 124 A — General View of Pleasant Valley Reservoir Site on Tule River 140 B — Looking Across Main Dam Site from South End at Pleasant Valley Reservoir Site on Tule River 140 INDEX OF MAPS. Map No. 1 Area Irrigated in 1921 in Portions of San Joaquin Valley in and Adjacent to Tulare County In Pocket 2 Ground Water Contours of San Joaquin Valley in Tulare County and Adjacent Areas In Pocket 3 Change in Ground Water Elevations from November 1. 1920. to November 1, 1921 .In Pocket 4 Average Depths of Ground Water — November 1, 1921 In Pocket 5 Ward Reservoir Site on Kaweah River below Three Rivers In Pocket 6 Pleasant Valley Reservoir Site on Tule River In Pocket 7 Reservoir Site on South Fork of Tule River at Head of South Tule Independent Ditch In Pocket INTRODUCTION. The following report is based on» Held investigations and study of data relating to the water resources of the portions of Tulare County dependent on the Kaweah and Tule rivers and on smaller streams in the southern portion of the county. The portions of the county dependent on Kings River for its water supply were not included. Some areas in eastern Kings County have been included as they are a part of the areas affected by Tulare County streams. The work on which the report is based was undertaken by the State Department of Engineering in May, 1920, and has been continued since the reorganization of the state's engineering work in July, 1921, by the Division of Engineering and Irrigation of the Department of Public Works. The work was undertaken at the recpiest of those interested in the development of the water resources of the county, expressed through the organization of the Tulare County Water Users Associa- tion. The costs of the work have been paid by the state, Tulare County, and the Tulare County Water Users Association. The total cost has been about $22,000 of' which Tulare County has supplied $7,500, the Water Users Association $2,500, and the state $12,000. The work has been materially assisted by the cooperation of all parties having data relating to the water supply and its use. Without such cooperation it would not have been possible to have secured the. extent of data on which this report is based within the time given to the field work and the indebtedness to such assistance is gratefully acknowledged. Special acknowledgment should be made to the Tulare County Water Users Association and its officers, and to all parties concerned in the pending litigation on Kaweah River, to the Southern California Edison Com- pany and to the landowners who have furnished data in connection with the ground water studies. The general planning of the work and its supervision has been under the direction of Mr. S. T. Harding. Mr. Chester Marliave has carried out the field work on the Tule River and southern portion of the county and Mr. G. H. Russell has handled the investigations relating to the Kaweah River areas. The report has been written by Mr. Harding assisted by both field engineers. The full utilization of the water resources of Tulare County requires a coordination of the use by direct diversion and by pumping of ground water. The extent to which present use of the available water supply has been extended is greater than is realized by many as the recent development has proceeded largely by means of individual pumping plants. The increase in such plants does not come to public attention to the same extent as the construction of canal systems. No develop- ment of the water resources of the county can be complete which does not fully utilize the available ground water supplies but it must be remembered that a ground water supply like those flowing in streams has limits to its volume and development can not exceed such limits without depletion of the supply. A large part of the field work in these investigations has been directed toward a study of ground water conditions and use as there had been less data collected on these subjects than on the extent and use of surface streams. 10 DEPARTMENT OF PUBLIC WORKS. The method of presentation consists of a discussion of the more general factors relating to irrigation including the records of run-off of the tributary streams followed by»a detail discussion of the conditions in each of the portions of the area covered for which physical conditions makes the water supply relatively separate and distinct. For con- venience in following the purpose and the relation of the different factors in the detail report a brief summary of the conclusions is pre- sented at this point. The divisions of the area used are shown on Map 2 and the areas irrigated in 1921 on Map 1. SUMMARY AND CONCLUSIONS. Water Supply. 1. The only sources of water supply available to this area are the discharges of the streams entering the area as surface flow except in the southwestern part of the county where the ground water is derived from mingled sources. 2. The records available on Kaweah River indicate that the total long time mean annual discharge is 451.000 acre-feet, Measurements made in these investigations show no appreciable seepage from the river above McKay Point, 3. The records available on Tule River indicate a total long time mean annual discharge of 106,000 acre-feet from the main Tule River, 29.000 acre-feet from the South Fork and 2000 acre-feet from areas below the gaging station or a total of 137,000 acre-feet for the entire drainage area. 4. An analysis of the available data on the smaller drainage areas gives an estimated mean annual discharge of Deer Creek of 19,000 acre-feet ; of White Creek of 6300 acre-feet and for other miscellaneous areas of 20,500 acre-feet. For all areas including Kaweah and Tule rivers the total mean annual run-off is estimated to be 633,700 acre-feet. 5. The mean annual outflow or surface discharge from Kaweah delta is estimated as 55,000 acre-feet. This represents the water leav- ing the Kaweah delta. Of the total estimated outflow in the last eighteen years, 80 per cent occurred in the three years of largest run-off. 6. Similar estimates of the outflow of Tule River indicate a mean annual discharge of 17,000 acre-feet, appreciable outflow having occurred in only eleven years of the last thirty-two years. No outflow from other drainage areas occurs. .— PART II. UTILIZATION OF THE RUN-OFF OF KAWEAH RIVER. 7. Available records of the diversions by Kaweah River ditches are given with a discussion of the indicated loss from river channels. 8. The areas served by ditches diverting from Kaweah River is estimated as 101,828 acres of which about one-fourth also receives supplemental water by pumping. 9. The general average diversion for Kaweah River ditches is estimated as about 2.9 acre-feet per acre. 10. The total irrigated area dependent on Kaweah River for its water supply either by canal diversion or pumping is estimated to be 175,000 acres. This is equivalent to one acre for each 2.3 acre-feet of mean annual available water supply. WATER RESOURCES OF TULARE COUNTY. 11 11. There were about 8500 acres of additional land subirrigated from Kaweah River in 1920. 12. The estimated total met pumping- draft in 1920 on the Kaweah River area is estimated to have been 162,000 acre-feet. 13. An investigation of sources of possible loss of ground water from the Kaweah area by outward movement into other areas results in the conclusion that such losses do not occur. 14. The ground water fluctuations for each year since 1917 are analyzed. The lowering for the whole area in 1920 and 1921 indicates an amount of loss of ground water storage about equal to the deficiency in the available run-off for these two years. On this basis present development is consuming the mean net annual available water supply. 15. A gross area of 135,000 acres within which the main canal service occurs maintained its ground water elevation in 1921. About one-half of the total irrigated area is within this area. In the other portions of the area there was a lowering of the ground water, the amount vary- ing with the extent of the pumping draft and the distance to direct sources of replenishment. The ground water conditions for the differ- ent parts of the area are discussed in detail. 16. Available storage sites are considered. The only site having sufficient capacity to regulate the Kaweah" River is the Ward site. Costs for different capacities are given with the conclusion that for full regulation of the run-off a regulated supply of 375,000 acre-feet per year supported by 150,000 acre-feet of storage capacity is as large as is feasible under existing conditions of run-off and storage costs. Such storage would represent a change in method of use rather than the addition of any material amounts of new water supply. As the esti- mated cost of storage alone is $7,500,000 such construction is not recommended. 17. It is estimated that power development at the dam for 150.000 acre-feet of storage might be able to produce a sufficient earning in excess of direct costs to carry about $1,000,000 of the cost of the dam. 18. The storage of winter flow and summer surplus waters would permit the securing of a fairly dependable annual supply of 50,000 acre-feet with 50,000 acre-feet of storage capacitv at an estimated cost for storage of $3,500,000. 19. The storage of winter flow only would permit obtaining a fairly dependable annual supply of 15,000 acre-feet with 50,000 acre-feet of storage capacity. 20. The storage of excess summer flood flow only would require an extent and cost of storage in excess of present standards of feasible cost. 21. The possible means of improving present conditions of use on the Kaweah area are discussed with the following suggestions as to the changes most likely to be feasible: 1. Complete a determination of existing rights on a basis which protects existing diversions in their essential needs but in which the standards of practice required are commensurate with present economic conditions of value of land and water. Such a determina- tion should include a definition of the rates of diversion to which each right is entitled and a limitation of the season in which such rights 12 DEPARTMENT OF PUBLIC WORKS. may be exercised. It may be secured through existing legal means or probably much more quickly and effectively by voluntary adjust- ment among the parties concerned if agreement by such methods can be reached. 2. Improve existing canals so as to reduce seepage losses in areas near the stream so as to deliver a larger part of the diversion to areas away from the stream in which ground water is now lowering. Increase canal capacities for those systems serving such outer areas. 3. Increase pumping in areas near the river channels using pumped water as a substitute for present canal use in these areas so that the present canal use can be transferred to areas of deficient ground water supply. This will also increase ground water storage capacity for absorption of flood flow from the river channels. 4. Permit use of winter flow by storage for upper lands either in surface or ground water basins or a combination of both as may prove to be most economical. 5. Make direct transfers of present canal use from areas of less production per unit of water supply to those of a higher type of use where such transfers can be arranged. 22. It is considered that it is to the interest both of the individuals concerned and of the community as a whole that land on which the cost of development has already been incurred should have its water supply protected before additional lands are brought under irrigation. Such developed lands can offer security for higher costs in securing the water needed to supplement their existing supply than lands not developed and requiring a complete water supply. 23. The continuance without change of present conditions of diver- sion and pumping must eventually result in a reduction in the areas now irrigated in some parts of the Kaweah delta due to the increase of the lift to a point where pumping will no longer be profitable. UTILIZATION OF WATER SUPPLY OF SOUTHERN PART OF TULARE COUNTY. Tule River Area. 24. There was a total area of 63,703 acres irrigated in 1921 in the area considered to be dependent on Tule River for such water supply as it may receive. This is equivalent to one acre irrigated for each 1.9 acre-feet of mean annual available run-off. 25. An area of 16,723 acres received some canal irrigation in 1921. Over 80 per cent of this area also received some pumped water. 26. The total pumping draft in 1921 was 132,000 acre-feet. 27. The ground water conditions are discussed in detail for the various parts of the area with the following conclusions: 1. The present pumping draft closely approaches the total mean annual available run-off of Tule River. 2. While the general conditions are relatively favorable for the addition of a large part of the run-off of Tule River to the ground water, the present draft exceeds the average replenishment. 3. A consideration of the conditions on the different parts of the area shows that the greatest lowering of the ground water has occurred on those areas least directly supplied and at the greatest WATER RESOURCES OP TULARE COUNTY. 13 distance from sources of percolation. The maintenance of present conditions can only be expected to result in a continued lowering of the water table in such areas. 4. Any increase in draft on such outer portions will directly increase the rate of lowering of the ground water. Any increase in draft in the portions of the area adjacent to sources of percolation will indirectly increase the lowering of the outer area by a reduction in the ground water supply available for outward movement. 28. The most dasirable reservoir site on the Main Tule River is at Pleasant Valley. A storage of 50,000 acre-feet capacity with an esti- mated cost of $2,050,000 would give a fairly dependable regulated sup- ply of 100,000 acre-feet per year. 29. On the South Fork of Tule River a reservoir could be built below the Indian Reservation with a capacity of 5000 acre-feet at an estimated cost of $535,000 which would support a fairly dependable regulated supply of 20,000 acre-feet. 30. A combination of 60,000 acre-feet of storage at Pleasant Valley and 5000 acre-feet on South Fork would support a regulated annual supply of 120,000 acre-feet at an estimated total storage cost of $2,750,000. 31. As such storage represents mainly a change in method of use and does not make available any materially larger part of the run-off of these streams than are now used by other methods their construction is not recommended. Deer Creek Area. 32. A total area of 15,447 acres, of which the Terra Bella Irrigation District supplied 3841 acres were irrigated in the Deer Creek area in 1921. The total pumping draft was 35,000 acre-feet or nearly twice the estimated mean annual run-off of Deer Creek, an average lowering of the ground water of two feet occurred in 1921. White Creek Area. 33. An area of 11,600 acres was irrigated in 1921 in the area consid- ered to be dependent on White Creek for such ground water supply as it may receive. The total pumping draft was 27,000 acre-feet or about four times the estimated mean annual run-off of White Creek. An average lowering of the ground water of 1.3 feet occurred in 1921. 34. There was an area of 10,800 acres irrigated in 1921 in the area in southwestern Tulare County considered to have ground water supplied from mingled sources. The total pumping draft within the area was 9500 acre-feet. The water rose an average of one foot in 1921. No estimates of the amount of the available ground water can be made for this area. 35. The investigations were extended into the northern edge of Kern County. Similar conditions of draft in excess of tributary water sup- ply with a resulting lowering of the ground water were found as in parts of southern Tulare County. 14 DEPARTMENT OP PUBLIC WORKS. MAIN REPORT. Chapter I. GENERAL FEATURES. Climate. The climatic conditions in the San Joaquin Valley portions of Tulare County are such that while irrigation is essential for full crop production a wide variety of crops can be produced. Temperature con- ditions vary in different localities so that the growth of certain crops is limited to special areas but there are no portions of the area in which crops can not be profitably grown. The larger portion of the areas is suited to orchards, either citrus or deciduous, including vines. For those portions where local conditions may be less favorable for orchards a sufficiently wide variety of other crops are available to make irrigation profitable. No detail consideration has been given to temperature con- ditions in these investigations. The precipitation of the areas furnishing the run-off for the water sll PPly is discussed in the next chapter. For the agricultural portions of the county the rainfall is limited in amount and confined in its occur- rence to the winter months. The mean annual rainfall is 10.31 inches at Visalia, 10.02 inches at Porterville and 16.71 inches at Lemon Cove. While such precipitation enables grain to be grown in many years without irrigation it is not sufficient for more intensive cultivation. It is doubtful if any of the winter precipitation reaches the ground water directly on the area on which it falls although there may be some incre- ment to the ground water in areas of high water table in years of excessive rainfall. Soils. The portion of Tulare County in the San Joaquin Valley is included in the areas of the Reconnaissance Soil Survey of the Middle San Joaquin Valley published by the U. S. Bureau of Soils except the southern nine miles of the county, which is included in the Reconnais- sance Soil Survey of the Upper San Joaquin Valley. While the soil texture varies widely in different parts of the area, there are few localities in which the soil is sufficiently unfavorable to control development. The deltas of Kaweah and Tule rivers are largely sandy loams, fine sandy loams and loams. Nearer the side of the valley between the streams the soils tend to be heavier and in some cases have hardpan within six feet of the surface. Alkali in sufficient amounts to affect crop growth occurs in portions of the area, particularly in the western part of the county. There is, however, adjacent to all streams an area of good land in excess of the area which the water supplies are capable of irrigating. The differences in soil texture affect the irrigation practice both as to frequency and amount of single irrigations and as to the total use per season. In some portions of the area ground water also affects the conditions of surface application, the ground water being sufficiently high to result in its direct use by the plants. WATER RESOURCES OF TULARE COUNTY. 15 Crops. In all parte of the irrigated areas in Tulare County there are a sufficient variety of crops which can be grown to make irrigation desirable. The crop distribution varies with the conditions of tempera- ture, water supply and soil. In the areas adjacent to the upper edges of the valley citrus fruits, olives and vines are largely grown. In intermediate areas vines and deciduous fruits are mingled with general crops. In the western portion of the county the proportion of alfalfa and summer crops such as corn is larger. The crop distribution is affected both by temperature conditions and by the cost of water, the crops of larger water requirement being grown more generally in areas of lower pumping lifts. The yields of all classes of crops where properly handled with adecpiate water supplies compare well with those obtained in other areas. Some areas not directly cultivated under irrigation are used for pasturage, being irrigated at such times as excess water may be available. Some land of high ground water is also used for pasturage without direct irrigation. 16 DEPARTMENT OF PUBLIC WORKS. Chapter II. WATER SUPPLY. The water supply for the portion of Tulare County in the San Joaquin Valley can come from only three sources. These are (1) visi- ble surface flow of streams entering the area; (2) invisible subsurface ground water movement; and (3) direct precipitation on the area. The first of these sources can be measured and sufficient records are available for the greater portion of the drainage area tributary to the valley lands to furnish a dependable basis for determining the run-off. The extent of the natural precipitation has been given and the opinion expressed that this adds little if any supply to the ground water. The natural precipitation on the valley lands is of benefit to plants by direct use and reduces the amount of water it is necessary to apply by irriga- tion. It does not, however, add materially to the water supply available for irrigation. The subsurface ground water movement into this area from outside areas, if such movements exist, would be difficult to measure. Their study can best be approached by a process of elimination of possible sources of such supply. There are three possible general sources from which ground water might move into the area covered by these investigations. One of these is ground water movement from areas supplied by Kings River water. The ground water contuors shown on Map 2 and the detail records of wells discussed later indicate that there is little if any movement south of Cottonwood Creek of any water supply derived from Kings River. The second possible source is general San Joaquin Valley ground water moving northerly from the south end of the valley. This affects some areas in the southwestern portion of the county. Its extent is discussed in connection with the discussion of the ground water there. The ground water contours on Map 2 demonstrate that such sources can not affect the higher lying ground water of any of the areas except the southwestern part of the county. The third possible source is deep movements westerly under the valley of water absorbed within the Sierra Xevadas. Belief in the existence of such a source of supply has been expressed by various individuals during the progress of this work and some discussion of the probabilities of its occurrence is considered warranted. The formation of the Sierra Nevadas is generally granitic and of an older geological age than the valley formations. The present San Joaquin Valley is the result of the filling by erosion from the adjacent mountains. Portion of such filling have taken place while the valley was submerged giving sediments more or less stratified ; other portions have taken place, as at present, as deposits by streams giving the alluvial formations which compose the recent valley fill. The total depths of these different deposits is not known but is considered to be several thousand feet in the central portion of the valley, wells over 4000 feet in depth have not reached the underlying formation. In order for water absorbed on the upper drainage areas within the Sierras to reach these valley fills by underground movement it would have to pass through the granite and into the valley fills. While ground WATER RESOURCES OF TULARE COUNTY. 17 water may exist in granitic formations, its amount and movement are small except along lines of fracture or faulting. It would be contrary to experience in other areas to expect any material amount of such movement here. The greatest losses would naturally by expected to occur along present stream channels. Measurements given later show that there is no appreciable loss from the Kaweah River channel above McKay Point. Pumping near Lindsay lowered the water level to a considerable depth, general ground water movement from the upper areas, if it existed in this area, should have served to maintain the pumping supply adjacent to the hills. Except for the two marginal areas first mentioned all of the water supply for the areas in Tulare County can be considered as entering the area as surface run-off in the definite stream channels. The extent of such run-off measures the extent of the water supply tributary to the area and available for irrigation. The available records are mainly those obtained by the Water Resources Branch of the U. S. Geological Survey since 1901 with some additional records secured by local inter- ests. Estimates of the run-off from 1878 to 1884 have been published based on the data obtained during this period by the State Engineer. As such records are based on less detail of observation than those more recently obtained and as the results are in many cases inconsistent with the more complete, recent records no use has been made of the earlier estimates. In these investigations no study has been given to the feasibility of bringing into this area water supplies not naturally tributary thereto. Such studies are outside the scope and purpose of this work. There can be no question, however, that full utilization of local sources of water supply should take precedence over any plans for securing distant sources of supply. KAWEAH RIVER. Kaweah River is the largest stream in Tulare County and supplies about two-thirds of the area irrigated. The run-off of the main stream has been measured by the U. S. Geological Survey below Three Rivers since 1903. Records are also available for the North and South Forks since 1911. Records at McKay Point have been kept since October, 1916, by Mr. H. H. Holley for parties interested in the diversions from the river. The power companies which have plants on the Middle Fork have kept records on East and Marble Forks as well as Middle Fork. All of these records have been made available for the purposes of this report. The run-off of the separate branches of Kaweah River is not of direct interest in the study of the utilization of this stream for irrigation as no reservoir sites of sufficient size to be important were found on these branches. The only site offering possibilities of full regulation of the stream is below the junction of the three forks at Three Rivers. The run-off of the main stream at Three Rivers gives the total supply avail- able for irrigation. The record of the U. S. Geological Survey station at Three Rivers during 1918 to 1920 is open to some question due to uncertainty as to the accuracy of the reported gage heights on which it is based. A somewhat detailed analysis of these records for this period has been 2 — 21044 18 DEPARTMENT OF PUBLIC WORKS. made and a substitute record of discharge used. The method of deriv- ing this substitute record is explained in detail later. For the period 1903 to date the run-off of the Kaweah River at Three Rivers is shown in Table 1. The records, except for 1919 and 1920 are those of the U. S. Geological Survey. The annual mean for the 18-year period is 455,000 acre-feet. Rainfall records for this vicinity are avail- able since 1890. A study of these indicates that the precipitation for the period 1890 to 1903 was only 93 per cent of that for the period 1903 to 1921 and that the recorded run-off for the latter period would exceed the mean for the longer period 1890 to date. A comparison by years indicated an average annual run-off of 416,000 acre-feet for the period 1890 to 1903 which combined with the recorded run-off since 1903 gives a mean annual discharge for the period 1890 to date at Three Rivers of 438,000 acre-feet. The estimated run-off of the small streams entering below Three Rivers, as given later, is 13,000 acre-feet per year, giving a total mean annual run-off of the Kaweah drainage area of 451,000 acre-feet. TABLE i. Discharge of Kaweah River at Three Rivers. Record of U. S. Geological Survey, Except for 1919 and 1920, for Which Discharge is Computed from McKay Point. Month October November . December. January February., March April May June July August September. Total for season. Discharge in total acre-feet 1903 1903-04 1904-05 123,406 104,073 28,407 3,074 2,559 2,644 3,332 2,951 4,796 41,933 39,352 57,600 126,296 62.598 13,527 6,641 11,306 373,000 31,420 6.962 5,841 7,133 14,330 34.000 46.590 85.220 80,210 18,620 4,710 2,690 338,000 1905-06 1906-07 2,669 3,368 5.103 48,200 23,200 150,000 114.000 197,000 278,000 211,000 42,500 13,400 1,090,000 7,380 7,080 15,100 25,300 33,300 63,300 117,000 120,000 121,000 62,700 16,000 5.380 594,000 1907-08 6,890 6.250 12,100 12.700 18,800 36.800 47,200 54.500 35,900 11,400 5,250 4,850 253,000 1908-09 1909-10 6.1160 4,260 5.240 92,200 77,200 53.400 89,800 162,000 217,000 70,100 16,000 6,600 800,000 5,670 13,000 46,600 50,600 25,900 48,700 79,100 86,700 34,900 12,000 3,680 2,880 410,000 1910-11 4,430 4,240 6.580 53.400 35,800 70,100 75,600 106,000 122,000 51,800 11,400 4,680 546,000 1911-12 4,800 4.960 5,570 6,270 6.040 12,200 22,500 67,600 61.300 10,600 3,360 2,210 207,000 Month October November December January February March April May June July August September Total for season Discharge in total acre-feet 1912-13 1913-14 1914-15 1915-16 1916-17 1917-18 1918-19 2 340 3,040 2,900 5,020 7,610 15,400 37,800 68,200 43,100 15,600 10,700 8,990 221,000 3,070 6,550 7,380 71,900 33,700 51,500 67,200 108,000 86,300 38,700 7,500 4,240 486,000 4,300 3,460 4,950 8,300 19,200 27,000 52,800 104,000 105,000 30,700 6.400 3,400 370,000 2.640 3,370 7,620 94,100 61,600 108,000 127,000 145,000 131,000 59,000 16,700 6,130 ^62,000 19,600 8,630 17,400 17,200 38,300 35,700 70,800 102,000 120,000 30,600 7,870 3,370 471,000 3,040 3,300 3,370 3,460 7,890 33.500 46,900 65,200 46,200 9,720 3,200 3,920 230,000 9,900 8,510 8,790 6,500 22.100 29,300 58 800 99,000 32,900 9,250 2,650 1,490 289,190 1919-20 1920-21 2,400 2,740 9,100 6.030 8,400 37,900 72,900 116,500 86,100 22.500 4,900 2,650 372,120 7,810 8,750 9,590 16,500 23,700 54,700 49,300 89,200 85,100 20,000 4,060 2,610 371310 WATER RESOURCES OF TULARE COUNTY. 19 The run-off: of Kaweah River is subject to relatively wide variations in different years as shown in Table 1. The maximum measured annual run-off at Three Rivers since 1903 is 1,090,000 acre-feet, the minimum is 207,000 acre-feet. Two consecutive years, 1912 and 1913, have had a mean discharge of 211,000 acre-feet or less than one-half the normal. Of recent years. 1916 was a year of excessive run-off; 1917 was about normal; and the last four years have varied from 53 to 89 per cent of normal. The four years 1918 to 1921 are the longest period of record in which no year had a run-off equal to or greater than normal. Accuracy of Kaweah River Records, The records of run-off of the Kaweah River at Three Rivers as obtained by the U. S. Geological Survey have been based on gage height readings taken usually twice per day. During the summer of 1921 an automatic register was also installed by Mr. H. H. Holley. During 1921 the gage height readings have been taken at 7 a.m. and 7 p.m. The resulting discharges as obtained by the recording gages and the two gage height readings are shown in the following table. The same rating table was used for both computations so that the differ- ences in discharge are due to variations of the mean of two gage read- ings per day from the actual mean. Month ,. Mean ,. M , ean discharge, discharge, , 2 gage height recording gage. readings> sacond-fect , se r 3 nd-feet Difference, second-feet Difference, per cent April _._ 826 1,440 1,430 780 1,360 1,320 46 80 110 5.6 May 5.6 June .— _ 7.6 These records indicate that two readings per day at the hours used give a smaller discharge than the actual at this station during the months of snow water flow. This difference is due to the fluctuation of the discharge during the day caused by the variations in the hourly rate of snow melting. As the three tributaries of the Kaweah have an approximately equal length of channel to the portions of their drainage areas contributing the larger portion of the run-off the daily peak of each branch coincides in time at the Three Rivers station. This results in a greater range of daily discharge than would be expected on most of such streams. These daily variations are limited to the months of melted snow flow. Discharge, during the rainy season, does not show similar variations. Typical records are shown in Fig. I. The comparisons made in 1921 might be used as a basis for a conclu- sion that the discharge at Three Rivers as published is less than the actual discharge and that some increase in such records would be warranted. Any such corrections would apply only in the summer months and the amount of the correction would depend on the actual time of reading of the gage. The actual time of reading of the gage in the past is not definitely known although it was probably in the early morning and toward evening. The uncertainties as to the time of read- ing make the application of a correction inadvisable. The conclusion 20 DEPARTMENT OF PUBLIC WORKS. appears warranted, however, that the actual discharge at Three Rivers is probably slightly more rather than less than the amount shown by the record. Kaweah River Records 1919 and 1920. Since 1916 a record of the discharge of Kaweah River at McKay Point has been kept by the canals interested in the division of now at that point, the actual record being secured under the supervision of Mr. H. H. Ilolley, engineer for the canal association. A comparison of the record at McKay Point with that at Three Rivers indicated differ- ences not explainable by intermediate diversions. These differences began to occur late in 1918. In order to secure a check on the Three Rivers record an automatic register was installed at Three Rivers in 1921 by Mr. Holley. A change was also made in the Geological Survey observer. The records during 1921 (Table 2) indicated a close agree- ment of the discharge at Three Rivers and at McKay Point when allowances for intermediate diversions are made. As the Three Rivers record for 1919 and 1920 appears to be based on inaccurate gage height records a substitute record has been prepared based on the McKay Point record plus the intermediate diversions. 1 <5 JOOO £fOO zooo /?oo /ooo SCO 5 r^?'ScAy ^b/^/ a>v */&/?c>//7/ &g>^c/c>s7 /futomaf/c f?eg/'$fe'~*s , WATER RESOURCES OF TULARE COUNTY. 21 TABLE 2. Comparison of U. S. Geological Survey Record of Discharge of Kaweah River at Three Rivers for 1918-1921 with Record Computed by Adding Intermediate Diversions to Discharge of Kaweah River at McKay Point. Total acre-feet, 1918-19 Total acre-feet, 1919-20 Total acre-feet, 1920-21 Month Com- puted U.S.G.S. Difference U.S.G.S. minus computed Com- puted U.S.G.S. Difference U.S.G.S. minus computed Com- puted U.S.G.S. Difference U.S.G.S. minus computed October _ . . *9,900 *8,510 *8,790 6,500 22,100 29,300 58,800 99,000 32,900 9,250 2,650 1,490 9,900 8,510 8,790 6,640 18,900 26,300 66,000 99,000 29,400 7,130 2,410 2,340 2,400 2,740 9,100 6,030 8,400 37,900 72,900 116,500 86,100 22,500 4,900 2,650 3,880 3,620 29,100 7,190 9,610 60,100 69,600 108,000 97,000 22,800 5,830 3,660 + 1,480 +880 +20,000 + 1,160 +1,210 +22,200 —3,300 —8,500 +10,900 +300 +930 + 1,010 6.350 7,910 9,470 15,700 22,700 45,500 51,000 89,500 84,400 21,270 4,140 2,850 7,810 8,750 9,590 16,500 23,700 54,700 49,300 89,200 85,100 20,000 4.060 2,610 +1,460 November . +840 December . +120 January February. . March April. .. _ May___ __ +140 —3,200 —3,000 +7,200 +800 +1,000 +9,200 —1,700 —300 June July August September . —3,500 —2,120 —240 +850 +700 —1,270 —80 —240 Totals... 289,190 285,320 —3,870 372,120 420,390 +48,270 360,790 371,310 +10,530 "U. S. Geological Survey record used. The McKay Point record since 1917 has been secured by means of an automatic register. The rating is controlled by the weir used to divide the flow between the Kaweah and St. Johns channels. The records of diversion (secured by Mr. Holley) of the canals diverting between Three Rivers and McKay Point are not complete and estimates have been used for portions of the record. The estimates are con- sidered to be fairly accurate as the diversions are relatively uniform and the amounts estimated are a small part of the computed totals. The intermediate run-off between Three Rivers and McKay Point was relatively small in all of the years used in these comparisons. Plate I, Figure A. Division Weir at McKay Point. 22 DEPARTMENT OP PUBLIC WORKS. The agreement of the Three Rivers and McKay Point records for a typical period in 1921 as well as the extent of daily fluctuation are shown in Fig. 1. The difference in discharge is due to intermediate diversions. At the dates where the river is rising the time difference between Three Rivers and McKay Point, a distance of 9 miles is only one to two hours ; on other dates when the river is falling the difference in time is about seven hours. The extent of the daily fluctuations indi- cates the probability of error where records are based on single gage readings. The river rises for about six hours during the day and recedes during the other eighteen hours. These period correspond with the time of melting at the higher altitudes. The percentage fluctua- tions at McKay Point are larger than at Three Rivers indicating that there is no spreading out of the maximums or minimums in the stream channel between these two points. Other comparisons were tried in order to check the Three Rivers records. The total annual discharge of the Kaweah River was com- pared with that of the Kings and Tub 1 rivers. The variations in the ratio of run-off in different years are greater than the variations in the nHks^i^^* F ■ 1 v m m " T 3 «** ■ I I * W^ m 1 1 4 * '•".. i - ■ ^BIB^^**" j?Jgj • - ^^■Wii'tjr i . wfiffl E&^2^^a23^^l Plate I, Figure B. Gaging Station on Cross Creek at Hanford Road Bridge. years in question on the Kaweah River. Apparently the storms pro- ducing the larger portions of the precipitation vary in their distribution over these adjacent drainage areas in different years so that the rela- tionship of the resulting run-off is not consistent. A comparison of the sum of the records on the North, Middle and South forks with that at Three Rivers was also made. The records on the Middle Fork are kept by the power companies at their diversions. The South Fork record is not complete in recent years. While the records of these stations are based on gage readings only and can not be considered as dependable as the McKay Point record, they, in gen- eral, tend to support the McKay Point record in those months in which McKay Point differs from Three Rivers. WATER RESOURCES OP TULARE COUNTY. 23 As these comparisons indicated that the record computed for the discharge at Three Rivers was more consistent than the Three Rivers record, the computed results have been used for the years 1918-19 and 1919-20. For 1920-21 the Three Rivers record was used as it agrees quite consistently with that computed from McKay Point except during March. Channel Losses in Kaweah River. In order to determine whether there is any channel seepage either above or below Three Rivers a series of measurements were made dur- ing the low water period in August and September, 1921. Measure- ments were made of each of the three forks and of the diversions and the records at Three Rivers and McKay Point for the same dates secured. The results are shown in the following table : Upper measurement, second-feet Lower measurement, second-feet Diversions, second-feet Losses or gain, second-feet North Fork .. 2.84 4.82 1.79 1.0 43.30 3.02 2.92 +1.97 South Fork.. —0.90 Middle Fork ._ ._ .. Total 46.20 51.00 Kaweah River at Three Rivers Sta. +4.80 The gain on North Fork is considered to be due to return flow from irrigation diversions. The loss on South Fork occurs in the coarse material in the lower portion of its length. Measurements up the Middle Fork were not made due to conditions of diversion for power. There is probably little, if any, loss except by seepage from the power flumes which may be lost before reaching the river. From the junction of North and Middle Forks there appears to have been a gain of nearly five second-feet to the gaging station below Three Rivers, a distance of about four miles. In the nine miles between Three Rivers and McKay Point there was an indicated gain of seven second-feet. The extent to which these gains may continue throughout the year is not known. It is probable that they represent mainly ground seepage to the river channel from early season flood flow or diversion for irrigation rather than a continuous ground water movement. The conclusion appears warranted that there is at least no channel loss above McKay Point and that the flow at Three Rivers is the total run- off of the upper drainage area. The wells above McKay Point have in general given small yields, a further indication of lack of seepage. TULE RIVER. There are two points of measurement whose records give the principal part of the run-off of the Tule River drainage area. These are the stations (1) on the main river above the mouth of the South Fork and (2) on the South Fork. The run-off of the small area below these stations is discussed with the other minor drainage areas. 24 DEPARTMENT OP PUBLIC WORKS. Main Tule River. The record of the main stream gives the run-off from 266 square miles of drainage area including the Middle and North Forks and their tributaries. The drainage area extends back to the divide of the Kern River drainage at elevations of over 9000 feet along most of the crest. The North Fork of Middle Fork extends northward to the east of North Fork and receives the drainage of much of this higher area. The mean annual run-off of the North Fork of the Middle Fork appears to be about 900 acre-feet per square mile, of the South Fork of the Middle Fork about 600 acre-feet per square mile and for the remainder includ- ing the North Fork about 275 acre-feet per square mile. The record on the main stream is continuous since 1901. There are a few small diversions above the station but the record gives the water available for use below. Its accuracy is considered satisfactory. The records are based on daily gage heights. There are no continuous gage records available. The daily fluctuations due to snow melting are prob- ably less on this stream than on the Kaweah. The annual discharges are given in Table 3. TABLE 3. Runoff of Tule River Near Porterville, Above Mouth of South Fork. Drainage Area, 266 Square Miles. U. S. Geological Survey. Record o Month October November . December. January. . . February. . March April May June July August September _ Totals... Discharge in total acre-feet 1901 1901-02 1902-03 25,702 It. I'M 3,751 1,168 1,012 45,900 1,783 2,559 3,074 2,767 8,830 22,259 33,977 21,090 11,306 2,644 1,291 893 112,000 1,476 2,975 3,812 15,618 9,608 15,864 26,598 22,013 9,402 2.337 1,045 833 112,000 1903-04 1904-05 1,045 1,428 1,722 1,845 6,960 17,401 16,602 16,110 4,403 1,045 553 1,190 70.300 3,382 1,785 2,275 2,914 4,215 14,140 12,200 19,250 8,688 2,023 603 488 71,000 1905-06 775 2,523 5,792 30,700 11.100 84.200 45,900 66,400 57,800 22,300 5,180 2,820 :;:;:,. i hiii 1906-07 1907-08 1908-09 1909-10 2,370 2.900 5,970 14,300 15,800 21,800 45,500 20,800 15,600 5.060 2,260 1,780 154,000 2,830 3,150 6,520 7,130 15,200 18,200 10,600 10,100 "4,750 1,230 633 1,100 81,400 1,920 2,030 2,720 55,000 49,800 32,600 45,200 45,000 34,300 10.100 3,300 2,300 285,000 2,740 5,270 36,600 21,100 10,000 13,300 13,600 9,470 3,180 1,110 406 631 117,000 Discharge in tota acre-feet Month 1910-11 1911-12 1912-13 1913-14 1914-15 1915-16 1916-17 1917-18 1918-19 1919-20 1920-21 October 1,360 1,520 429 212 928 581 5,840 928 490 529 879 November.. 1,900 2,550 904 2,230 1,210 1,750 3,800 1,680 1,430 976 1,690 December _ . 2,980 2,930 1,390 4,180 2,560 3,790 12,600 2,180 2,790 3,230 3,070 January 17,800 4,000 1,740 44,400 4,500 58,200 9,410 2,370 2,490 1,920 4,960 February. . _ 15,100 3,370 1,640 14,300 9,720 33,200 19,300 2,870 6,500 2,160 8,500 March 26,900 5,450 5,130 14,300 10,600 51,800 16,100 12,800 13,500 18,100 14,400 April 21,000 9,700 7,970 15,900 14,900 38,700 23,000 8,930 15,600 25,600 9,640 May 17,400 12,200 6,210 16,500 37,400 33.200 24,800 5,810 12,100 20,700 15 300 June 10,800 6,720 2,950 9,640 16,100 18,500 17,500 1,960 2,700 9,340 8,930 July 3,380 842 445 2,480 3,510 6,200 3,640 167 259 1,510 1,090 August 1,330 175 142 627 744 2,240 1,150 56 34 194 98 September.. 988 314 278 397 625 1,200 547 159 18 209 57 Totals.... 121,000 49,800 29,200 125,000 103,000 249,000 i:i \m hi 39,900 57,911 84,468 68,614 WATER RESOURCES OF TULARE COUNTY. 25 The mean annual discharge of the main river station since 1901 has been 120.000 acre-feet. This record does not cover the dry period between 1890 and 1900. As the rainfall records begin in 1889, the measured run-off since 1901 was plotted against the rainfall for each year and the indicated relationship used to estimate the probable run- off for 1889 to 1900. The rainfall for these earlier years averaged 88 per cent of the long time mean. The resulting estimates of run-off averaged 88,000 acre-feet per year for this earlier period. For the full period, 1889 to 1921, the estimated and measured run-off indicates a mean annual discharge of 106,000 acre-feet per year for the area above the present gaging station on the main Tule River. For the period of actual record the years of smallest discharge were 1912 and 1913 with a total of 50,000 and 29,000 acre-feet respectively or 17 and 27 per cent of the probable long time mean. In 1918 the discharge was 38 per cent of the Ions* time mean. The largest measured discharge was in 1906 with 335,000 acre-feet or three times the long time mean. Two other years, 1909 and 1916, were 2| and 2^ times the mean. For the years 1889 to 1901 the estimates indicate a minimum discharge of 28.000 acre-feet in 1898 with no years exceeding 1.5 times the probable long time mean. For the long time period the discharge at the gaging station on the main Tule River appears to be derived about as follows : Drainage area Mean annual runoff, acre-feet Per cent of total South Fork of Middle Fork _.. ._ 25.000 30,000 5.000 46.000 23 North Fork of Middle Fork — 27 Bear Creek _ 5 Remainder of drainage area. _ __ _ _ 45 Totals . _ -. -- 106,000 100 South Fork of the Tule River. The records on the South Fork of Tule River began in 1910. The record is not complete for all parts of the period since 1910. The dis- charges are given in Table 1 in which the missing records which have been supplied by estimates based on comparison with the record of the main Tule River are indicated. For the eleven years of record the mean annual discharge has been 28,750 acre-feet. The maximum measured run-off has been 87,000 acre-feet in 1916 and the minimum 9010 acre-feet in 1913. In order to estimate the run-off on the South Fork over a longer period than that covered by the record, the recorded discharges on the South Fork were plotted against the discharge of the main Tule River. From the relationship indicated the discharges for previous years were estimated by comparison with the measured or estimated discharges on the main Tule River. For the period 1890 to 1921, the mean annual discharge of the South Fork of Tule River, as estimated on the above basis, appears to have been 29,000 acre-feet with variations from 8000 to 95,000 acre-feet in different years. 26 DEPARTMENT OP PUBLIC WORKS. The gaging: station on the South Fork is several miles above its entrance into the main stream. The gaging station on the main stream is also above the base of the hills. While the portion of the drainage area from which the run-off is not measured furnishes a rela- tively small part of the total discharge it has been estimated for pur- poses of completeness. The results are shown with those for all areas in Table 6. In minimum years the discharge is negligible ; in wet years it is estimated that as much as 9000 acre-feet of run-off may occur with an average of about 2000 acre-feet per year. The estimate for this lower area was based on the same methods that were used for other small unmeasured areas as explained later. TABLE 4. Runoff of South Fork of Tule River Near Porterville. Drainage Area, 76 Square Miles. Record of U. S. Geological Survey Except as Noted. Month Discharge in total acre-feet 1910-11 1911-12 1912-13 1913-14 1914-15 1915-16 1916-17 1917-18 1918-19 1919-20 1920-21 October November.. December. _ January February. _. March. April May June July August. September.. 302 780 916 3.210 2,850 6,760 4,560 2,860 1,480 481 196 162 440 509 719 615 555 1,640 4,150 3,740 1,830 595 210 158 285 546 555 941 944 1,650 1,830 1.040 684 303 112 152 132 584 1.760 15,300 4,670 4,090 5,360 4.110 1,570 658 151 165 326 405 818 1,440 2,850 3,190 4,320 14,300 4,250 1,380 435 256 264 738 2,340 21,600 12,500 18,800 13.000 9.900 4,630 1,920 849 496 1,680 *750 *1.000 2,800 *4,000 5,200 *5,000 *3,500 3,720 1,340 586 270 330 550 607 715 1,524 3,204 2,012 *1,200 *500 114 46 209 470 750 1,030 756 1,790 4,480 4,590 3,140 940 233 133 135 311 370 2,210 568 863 6,390 9,340 3,830 1,970 726 322 417 430 893 1,540 1,840 2,780 4,610 3.270 3,330 2,150 615 242 210 Totals ... 24,600 15,200 9,040 38,000 34,000 87,000 29,846 11,011 18,447 27,317 21,910 tions. 'Records incomplete; discharge estimated by comparison with Main Tule River in connection with these investiga- Summary for Entire Tule River Drainage Area. A summary of the run-off for the different parts of the Tule River drainage area gives a total estimated long time mean annual run-off of 137,000 acre-feet with a minimum of 36,000 acre-feet and a miximum of 439,000 acre-feet. For the thirty-two years covered by the records and estimates, there are three years in which the run-off exceeds twice the mean. The run-off in each of the last four years has been less than normal, the average for the four years being 59 per cent of normal. This is the longest period during the thirty-two years in which no year had a run-off at least equal to the mean. Run-off of Smaller Drainage Areas in Tulare County. In addition to Kaweah and Tule rivers there are Deer and White creeks and various other small drainage areas which discharge their run-off into the valley portion of Tulare County. Except for Deer and White creeks the discharge of these streams has not been measured. In order to make an estimate of the total water supply of the area some basis of estimating the discharge of such drainage areas is required. The method used has consisted of an estimate of the precipitation at different elevations on each drainage area with an estimate of the run- off resulting from such precipitation. The details of the method are WATER RESOURCES OP TULARE COUNTY. 27 discussed in Bulletin 9 of this office entitled "Water Resources of Kern River and Adjacent Streams and Their Utilization." The curves used for Tulare County are as shown in Figs. 2 and 3. Most of the precipitation records available are for relative low ele- vations. Precipitation increases with elevation ; the rate at which such increase occurs appears to be as indicated in Fig. 2, based on such records as are available. The relationship of rainfall and run-off as shown in Fig. 3 is also based on such records as are available. The curves for drainage areas for which the discharge has been measured were developed by trial. The curves for unmeasured areas were then estimated by comparison of the character of the drainage areas. 7000 6000 5000 ^ f' ' /?eA?//os7 o/Z^y^c/^/T^/yo/y 0/7c//T/e'^<2//c>/?^or 7~v/ Coo/7 fy S//t? sfs-&a& area below Hot Springs the rainfall run-off records for 'plains' condi- tions was used. From the parts, the run-off of the total drainage area was computed giving the curve shown in Fig. 4. The run-off curve for the entire "Deer Creek drainage area given in Fig. 4 gives results averaging about 18 per cent greater for 1920 and WATER RESOURCES OF TULARE COUNTY. 29 1921 than the measurements made by the Terra Bella Irrigation Dis- trict. The conditions in both of these years were such as to produce probably less than the average run-off from the precipitation. The run-off curve used appears, however, to give results as great, if not somewhat greater, than would probably be shown by a long direct record of run-off. \ ?nn s> ^ v * /50 $ fc S /oo * s I JO O SOOO ■ /OOOO /JOOO iOOOO 25&20 3000O /v« 4-. To^a/ 'y4/?/7c/a/ /Rw - o# ' — f^\ "^ /^.i "yi — - i(~> ■"•. ■ *■> r-* si" ©" co* ~- ec ©~ c- co*o©i>-rcrc©©»ft©roc^© »c x ■* t h- x ^" ^ ^ — t © © co > w X © © CJ © © :c co © »o © iO — CO CN -^ -^ © C-) ©©c v ix-«j'©:r^©©r--xc^cN©©©©io© © © — -*©©— ■Tt«©3CCS©t^-GCC v l©LCr— © ©coco©© , ***co©<— • co ~- c*3 ■*?■ © <"^ *•*■" r** *-T « 2 ©©iO© X CO CO — — •«*«© OJ © © © © 3C — © "*« — •»*« tf3 t^ 3 o iciccjcoifcc M'tci.'; — ©ic©©»c© x c; l<; c x :i l": - x t x :: - c ^ c c s 2 N*«X i*3 © CO ■OfiQ C*^l ©CO©X»-OC^CO© mV^' cs" — "co*co*«*^"c4"~-*cn"©'"~* * ci r-OCiMOcic:sNrtMCC: ~-cs©©rox©coi>-©t^(^c^ -h ?. c: u: X l- ~ r? ■* r. s s - © © lo © x © r» c>3 — » « U3 I © © © u-3 rC«NMMXNCr-L*CClX -N^XNfC^h.^XClN a © © ^ © -^ X lO otowr-xo © © — CN O) © © X C-} © CO © CO t- © — r- © c>j — ■ XhXWXMX CO : © © © © m < ©©©-*■© o* © — m * o — o s cc o z 0"00 o c; — -^ -*• » cq ~a ro « c^ t^» "3 O* C^ OO 2 o = ~ xnsc — -2 5 o ft. >> a gftS s CD cS 1 - 30 9 3 c ft. >> a * 2 5 = 5.2 = c o o *-*- — > o J> p cc a — 0.2 g 2-= 3 .. fc- ~ *- J? =j t- "rs -•"■=."= r: -3 5 s^ _ >> = ooo Mrco r — — o ■*• M 00 — Ci 3 . — - o 5d1Ja-xB^ '12 Si a 3 111 ~ '- '- x-5 X 48 DEPARTMENT OP PUBLIC WORKS. The records of both parties for 1917 were based on staff gage readings and current meter ratings. The records for 1920 and 1921 are based mainly on continuous gage height records of automatic registers. As the flow of the Kaweah River fluctuates materially during the day dur- ing the summer months as previously discussed, records of diversion based on continuous gage height records should be more dependable than those based on one or two daily readings. The run-off in 1917 was about normal, that for 1920 and 1921 was somewhat below normal. The diversions by the various canals will vary with the nature and extent of the flow in the river particularly for those ditches having later rights. The schedule under winch diversions are made is not sufficiently definite to enable the diversions of the different ditches in other years to be estimated on the basis of the flow in the stream and the priority of each ditch and no estimates for other years have been attempted. The flow of Kaweah River at McKay Point is either diverted by canals, percolates from the river channels or escapes from the Kaweah Delta through Cross Creek or other outlet channels. The records for the three years 1917, 1920 and 1921 are sufficient to enable the total canal diversions and the outflow to be determined with fair complete- ness. The difference between the sum of these items and the total supply is considered to represent seepage from the stream channels. The available diversion records by months for 1917 are summarized in Table 11, those for 1920 in Table 12 and those for 1921 in Table 13. The 1917 records do not indicate any large amount of unaccounted for flow. The difference between the sum of the measured canal diversions and Cross Creek outflow for the five months covered by the records is 14,050 acre-feet or 4.5 per cent of the total flow at McKay Point. This smaller percolation in 1917 might be expected as the year previous had been one of large run-off and the ground water elevations adjacent to the stream channels were higher in 1917 than in 1920 or 1921. The 1917 diversions records are also probably less accurate than those for 1920 and 1921. The 1920 diversion records indicate a larger channel seepage than those for 1917. If the outflow of Cross Creek for 1920 of about 9000 acre-feet is deducted, the remaining unaccounted for flow amounts to 20 per cent of the discharge at McKay Point. Any difference in chan- nel seepage that may have been caused by the pumping by the Lindsay- Strathmore Irrigation District during the months covered by the canal diversion records would be included in the above unaccounted for flow. The records for 1920-1921 cover the full run-off year. The unac- counted for flow in Table 13 is about 59,000 acre-feet. The outflow through Cross Creek for this period was 5000 acre-feet and the amount pumped for use within the Lindsay-Strathmore District was about 13.500 acre-feet. If the water used by the district is all assumed to have come from the flow at McKay Point during the period of record the remaining net unaccounted for supply becomes 40,500 acre-feet or 12 per cent of the total at McKay Point, As both of the years in which more complete diversion records are available were ones of similar but less than normal run-off, the channel seepage to be expected in years of excess run-off can not be estimated on the basis of the data available. It is probable that the actual amount WATER RESOURCES OF TULARE COUNTY. 49 of such channel seepage would increase with an increase in the amount of run-off but that the percentage of seepage would decrease. The available records indicate that there is a material addition to the ground water from such channel percolation. As the records were secured at the points of diversion of the St. Johns and Kaweah rivers or adjacent channels only the seepage from such channels are included in the figures given. Maximum Rate of Diversion by Canals from Kaweah River. The run-off in 1920 and 1921 being less than normal the total diver- sions for those years are also less than for years of larger run-off. Tliere were periods in the irrigation season of both years, however, when water was passing the lowest diversion. At such times it may be assumed that the diversion requirements of the various canals were fully satisfied. The conditions of total discharge under which outflow from the Kaweah Delta will occur have previously been discussed in detail. TABLE 14. Maximum Rates of Diversion by Kaweah River Ditches. Ditch Maximum weekly average diversion in 1917, second-feet Maximum weekly average diversion in 1920, second-feet Maximum weekly average diversion in 1921, second-feet Ditches diverting above McKay Point — Marks and Rice 2 3 7 11 117 3 Lemon Cove- _ _ __ 7 Merryman 2 11 Wiitphumna- 101 Totals 13S 6 4 48 517 221 30 16 37 17 30 67 391 24 31 58 31 89 25 362 '33 122 Ditches diverting below McKay Point— Hamilton' 6 4 6 Enlow 1 4 Lindsav-Strathmore Irrigation District _ ___ .. 48 Peoples Consolidated. . _ 502 172 35 11 41 14 26 67 429 12 29 43 36 163 25 282 33 362 Farmers ______ 191 Evans _ _ _ 30 Fleming ___ _ 15 Persian __ _ __ 73 Oakes _ 12 Watson__ __ 30 Tulare Irrigation Company 71 Tulare Irrigation District 357 Jennings. _ 23 Matthews 26 Modoc, __ 55 Uphill 26 Packwood 139 Goshen 2 25 Lakeside _ _ _ ___ 374 Wutchumna-Barton cut >33 Totals 1,930 2,037 1,900 'N'o direct records; figures given are estimates. 2 Based on estimated monthly means. The diversion records for each ditch were examined and the maximums assembled in Table 11. The weekly means have been used rather than the maximums for any single day. The total discharge of the Lindsav-Strathmore Irrigation District is included in Table 14 although it is taken from ground water adjacent to the stream and does -21044 50 DEPARTMENT OF PUBLIC WORKS. not affect the flow of the river by the amount pumped. Table 14 indi- cates that a total diversion of about 1950 second-feet below McKay Point and 2080 second-feet below Three Rivers will meet the simul- taneous maximum rates of diversion by these ditches. As all ditches will not actually be diverting at their maximum rate simultaneously somewhat smaller total diversions at any time will meet the total diversion needs. The previous discussion of outflow shows that a dis- charge of over 1900 second-feet at Three Rivers, if maintained, will result in outflow from the Kaweah Delta indicating that this rate of flow supplies the normal diversions plus the channel seepage. Areas Irrigated by Kaweah River Ditches. Various classifications of the lands irrigated by the different ditches diverting from the Kaweah River have been made by the parties to the litigation over the pumping by the Lindsay-Strathmore Irrigation Dis- trict. These classifications have resulted in a stipulation between the parties regarding the areas irrigated under several of the ditches. No attempt was made in connection with these investigations to canvass in the field the areas supplied by each ditch. Some areas partially served by ditches were included in the areas canvassed for pumping. The various classifications made by the parties to the litiga- tion were made available and were compared. Where material differ- ences were found sufficient investigations were made to enable a conclusion to be reached. The extent of the areas served was also checked with the officers of the different ditches. The resulting figures used for the areas served agree with those stipulated for the ditches covered by the stipulation and represent the results of the data collected in this investigation as to the other ditches. The results are shown in Table 15 and on Map 1. WATER RESOURCES OF TULARE COUNTY. 51 TABLE 15. Areas Served by Ditches Diverting from Kaweah River. Area in acres of Ditch Alfalfa Orchard and vines Field crops Wild pasture Total Receiving supplemental water by pumping Ditches diverting above McKay Point — Marks and Rice . 129 1.100 1,680 5.602 129 1,100 1.680 7,446 1,680 WntohiimnaS 870 814 160 4,253 Totals 870 15 8,511 50 160 6 9.370 4.445 250 1,378 814 115 300 40 160 270 1,140 364 10,355 450 1,600 540 2 9,370 14.569 5,637 7,635 5,933 Ditches diverting below McKay Point — Hamilton Long's Canal Enlow.. . . . 130 Lindsay-Strathmore Irrigation District *Peoples Consolidated . _ _ 4,088 4,150 2,850 4,265 776 2,840 1,771 461 297 4,127 *Elk Bayou 1,784 *Farmers . _ 3,594 Evans 1 . . *Fleming - .. 372 408 84 150 1,014 448 Persian 1 *Oakes 216 237 287 282 1,022 63 Watson 1 .. Evans-Persian- Watson 1 4,300 1,588 7,905 300 692 2,000 1,148 1,469 720 11,000 2.150 942 602 100 14 84 124 536 2 340 6,470 279 2,823 230 192 850 107 916 545 6,360 120 475 869 30 656 494 79 600 2,050 13,040 3,284 12,199 630 928 3,590 1,873 3,000 1,867 19,750 2,538 *Tnlare Irrigation Company. . _ 2,191 *Tulare Irrigation District . . . 2,771 Jennings .. _ . _ . 26 'Matthews 280 *Modoc . _ ._ _ 611 ♦Uphill 723 *Packwood . 2,626 *Goshen . . Lakeside... . 609 3,668 Totals 42,943 21,198 27,514 10.108 101,728 25.859 'Ditches for which areas given have been agreed upon by stipulation between parties to the pending litigation. •Area of Watson, Persian and Evans ditches combined. 2 Area irrigated in 1920; gross area in district about 15,000 acres. 3 Lands served by Wutchumna ditch on north side of river only. About 23 p;r cent of the use on this system is for variable areas on the south side of the river for which data is not available. 52 DEPARTMENT OF PUBLIC WORKS. The area supplied by ditches diverting from the Kaweah River is not definite as it varies from year to year with the extent of the run-off. Many areas use ditch water when available supplemented by water pumped from wells for periods when the ditch supply is deficient. The figures given in Table 15 are thought to represent, as closely as condi- tions will permit a classification to be made, the area generally served by ditches from the Kaweah River. The actual service given will vary from a complete supply during the full season to one irrigation in years of unfavorable run-off. Not all of the area given is irrigated in many seasons. The Peoples Consolidated Ditch received water over a longer season than most other ditches diverting from the Kaweah River. The ground water is higher than in manj^ other areas. The Elk Bayou receives its water by diversion through the Peoples Consolidated Ditch. The area covered by this system was canvassed in 1920 for pumping use and data also collected on the ditch irrigation for that season. The canvass gave a total area irrigated by ditches in 1920 of 4170 acres. The acreage agreed upon in the stipulation of 5637 acres represents the area prepared to receive ditch irrigation when the water supply is available. The areas irrigated under the Watson, Evans and Persian ditches overlap to a considerable extent, some lands receiving water from more than one of these ditches. The areas under the three ditches have been combined in Table 15. The acreage irrigated in any year in the Tulare Irrigation District varies more widely than under most of the other ditches as the water rights for this system are among the later priorities on the river. An area of 8540 acres was found to have received some irrigation from the (anal system in this district during 1920; the larger part of this area also received supplemental pumping supplies. Ground water conditions affect the area irrigated from the Uphill and Modoc ditches, the ground water being relatively high in some parts of the area served. The Paekwood and Goshen ditches receive water after the larger part of the other ditches are supplied and in consequence the area served is more variable from year to year. Supplemental pumping is also used to a greater extent than under many of the other ditches. The Lakeside Ditch serves an area which is to the west of Cross Creek and is considered to be outside of the area of the Kaweah Delta which is dependent for its ground water supply on the Kaweah River. The ground water conditions in the area supplied by the Lakeside Ditch are the result of its own diversions and of the use of Kings River waters on adjacent areas rather than of the use under other canals diverting from the Kaweah area. The Lakeside Ditch is one of the larger Kaweah canals and receives a considerable proportion of the water diverted from the Kaweah River. WATER RESOURCES OF TULARE COUNTY. 53 Plate IV, Figure A. Waste Gate on Lakeside Canal near the Diversion from Cross Creek. Plate IV, Figure B. Pasture Irrigation under the Lakeside Canal. Duty of Water Under Ditches. The data previously given for the diversions and the areas irrigated for the various ditches is assembled in Table 16 in terms of the rate of use of water per acre irrigated. The figures g"ven represent diversions, the amounts delivered to the farms would be less than the figures given by the amount of the conveyance losses, which for at least some of the ditches may be relatively high. Of the years shown in Table 16, the 54 DEPARTMENT OF PUBLIC WORKS. run-off in 1917 was slightly above normal. The years 1920 and 1921 were about five-sixths of normal. The figures given for the acre-feet per acre diverted are not a con- sistent basis for the comparison of the practice under the different ditches as the acreages used are in some cases larger than the areas actually supplied in these years. The flow of the Kaweah River becomes so small by August that only a limited area can receive a supply equal to their normal needs in the later part of the season. TABLE 16. Diversions in Acre-feet per Acre of Ditches Diverting from Kaweah River. Ditch Area supplied by ditch, acres Average acre-feet per acre supplied, diverted during season of — Apr. to Aug., 1917 Mar. to Aug , 1920 Oct. 1920 to Sept., 1921 Ditches diverting above McKay Point — 1,100 • 1,680 7,446 9.370 14,569 5,637 7,365 13,040 1.014 1,022 3,284 12,199 630 928 3 590 1,873 3,000 1.867 19,750 2.1 1.9 3.4 1.6 3.2 3.6 1.4 2.7 2.0 2.9 2.8 7.4 6.3 2.8 2.4 2.2 1.3 2 3 3 2.7 3.5 Ditches diverting below McKay Point — 15 | 3.3 3.3 1.7 2.6 2.6 4.3 5.1 4.1 5.1 2.7 2.7 5.5 Elk Bavou 3.3 2.7 Evans- Watson-Persian _ _ . _ 2.3 Fleming 3.5 3.0 Tulare Irrigation Company. .. 3.9 Tulare Irrigation District -- 2.8 7.8 6.1 2.8 Uphill 2.9 2.3 1.6 1.9 2.8 Mean _ - 3.0 2.7 2.9 Total Irrigated Areas Dependent on Kaweah River for Their Water Supply. The areas now irrigated which are dependent on the Kaweah River for such water supply as they may receive are larger than the areas served by ditches diverting from the river due to the additional areas for which pumping is practiced. The extent of the area whose under- ground water supply is dependent on water originating in the Kaweah River is not distinct but blends into adjacent areas. However, for the purposes of the study of the water resources and their use it is essential to delimit the area considered to be dependent on each source of water supply. This has been done as outlined on Map 2. The determination of the limits of each area has been based on the data collected regarding the ground water and its use as discussed in detail later. From the canvass of the areas served entirely by each pumping plant made in these investigations and the data on use under ditches, the total irrigated areas dependent on Kaweah River as given in Table 17 were determined. The location of the areas is shown on Map 1. The areas given in Table 17 represent the lands receiving a more or less complete irrigation supply in 1920. The sum of the figures given WATER RESOURCES OF TULARE COUNTY. 55 for areas supplied by ditches only and by ditch and pump are less than the sum of the figures given in Table 15 for each ditch as the data used in Table 17 is based on the lands actually receiving canal service as determined by field canvass under some of the ditches whereas the areas given in Table 15 for these ditches are larger than the areas actually supplied in 1920. The general areas used for some of the other ditches are probably larger than the areas actually supplied in 1920. For the year given the data in Table 17 is considered to represent fairly closely TABLE 17. Summary of Areas Irrigated in 1920 Which Are Considered to be Dependent on the Run-off of Kaweah River for Their Water Supply. Crop — acres Character of water supply — area in acres Total Area Orchard and vines Alfalfa Corn Grain Miscel- laneous, including pasture By ditch only By ditch and pump By pump only area in acres Main area of Kaweah Delta covered by canals diverting for lands below. Venice Hills _ Areas covered by canals divert- ing for lands mainly above Venice Hills 25,800 16,800 1,500 6,400 29,900 800 7,500 700 13,800 300 2,700 100 22,500 600 2,800 11,300 800 1,400 100 47,000 2,700 *900 18,900 6,900 *100 37,400 9,700 14,900 7,300 103,300 19,300 15,900 7,300 Area of lower Kaweah Delta outside of areas covered by canals Area west of Lindsay-Strath- more Irrigation District to- ward which ground water slopes from the Kaweah Delta Total of above areas Area irrigated by Lakeside Diteh 50,500 300 9,400 38,900 11,000 16,900 6,400 25,900 13,600 2,100 50,600 16,100 9,400 25,900 3,700 69,300 145,800 19,800 9,400 Area irrigated by Lindsay- Strathmore Irrigation Dis- trict Total 60,200 49,900 23,30:1 25,900 15,700 76,100 29,600 69,300 175,000 *Includes area east of Cross Creek. the total cropped area receiving irrigation with water originating in the run-off of Kaweah River. The supply for the full area shown was not complete as some lands dependent on canal irrigation alone receive deficient service during the latter part of the season. The data relat- ing to canal areas was collected in 1920, that relating to pumping in 1920 and 1921. The areas are later used as representing the lands irrigated in 1920 and 1921 as the increase in 1921 was relatively small. For purposes of study of the relations of recharge and draft on the ground water of the Kaweah Delta, the total area has been divided into four parts as shown on Map 2. The first of these includes all of the lands served by canals diverting for lands lying below Venice Hills. The outer boundaries extend beyond the areas usually served. This area includes all lands which can be expected to receive canal irrigation in any year by existing ditches and includes much land for which no canal system is now available. About 55 per cent of the gross area receives irrigation from some source of supply, about one-half of the area irrigated receiving only canal service. 56 DEPARTMENT OP PUBLIC WORKS. The second area includes the areas covered by canals diverting mainly for service above Venice Hills. It extends to Exeter on the south side of the river including the areas above the Peoples Ditch. On the north side of the river it covers the area along Cottonwood Creek served by the Wutchumna Ditch and adjacent lands. The third area covers those lands whose ground water is considered to be dependent on Kaweah River run-off for its replenishment but which does not receive any direct irrigation by canals. This division covers the area extending westerly from the main canal area to Cross Creek and southerly to the area dependent on Tule River. The fourth area includes the part of lands lying between the main deltas of Kaweah and Tule rivers toward which the ground water slopes from the Kaweah Delta. The present slopes may be the result of arti- ficial conditions of pumping draft as well as of natural conditions. This area extends easterly to the Lindsay-Strathmore Irrigation District and the upper canal area and southerly until the slope toward the Tule Delta is reached. These four divisions have been selected mainly for convenience in the study of ground water conditions. It is obvious that the boundaries used for any such classification can not be exact and that the differences in such factors as canal use, pumping draft and ground water fluctua- tions will tend to blend or merge along the boundaries selected. For convenience the boundaries have been made to follow section lines in most instances. The areas served by the Lakeside Ditch and the Lind- say-Strathmore Irrigation District are not included. Although these two systems receive Kaweah River water they are considered as being outside the Kaweah Delta and not affected by general ground water movement within the delta. The area supplied by the Lakeside Ditch included about 3700 acres which received supplemental pumping. There is also some supple- mental pumping within the Lindsay-Strathmore Irrigation District for which no direct data is available but which is understood to have been of small amount in 1920. The mean annual run-off of the Kaweah River has been previously estimated as 451,000 acre-feet of which an average of 55,000 acre-feet passes across the Kaweah Delta without diversion or absorption, leaving a net mean annual water supply of 396,000 acre-feet for the irrigation of lands dependent on this source of supply. The figures given in Table 17 indicate that there is now developed an acre of irrigated land for every 2.3 acre-feet of mean annual available water supply for irrigation. Deducting 45,000 acre-feet as the average diversion of the Lakeside Ditch and 15,000 acre-feet for the diversion of the Lindsay-Strathmore Irrigation District leaves an average supply of 336,000 acre-feet for the 146,000 acres now supplied on the Kaweah Delta or an average of 2.3 acre-feet per acre. Subirrigated Areas. In addition to the areas to which irrigation is applied from canals or by pumping there are some areas on which there is moisture drawn from the high ground water by capillary action. These subirrigated areas were classified by the Lindsay-Strathmore Irrigation District in 1917. This classification has been adjusted to the conditions of 1920 by WATER RESOURCES OF TULARE COUNTY. 57 comparison with the lowering of the ground water from 1917 to 1920. Only land is included in this classification which has not been included in the area receiving surface irrigation. There are areas receiving sur- face irrigation in which the ground water is sufficiently high to result in loss of moisture from the surface by direct draft by plants on the ground water. On the above basis it is estimated that in 1920 there were 1500 acres of cropped land and 1500 acres of pasture subirrigated under ditches and not credited as surface irrigated, and that in addition there were subirrigated area's along stream channels and not under any ditch system of 900 acres of crops and 4600 acres of pastures giving a total area of such subirrigated land of 8500 acres. Adding this area to the 175,000 acres surface irrigated gives a total cropped area dependent on the Kaweah River of 183,500 acres for which the average water supply available would be 2.2 acre-feet per acre. Rate of Increase In Area Irrigated by Kaweath River Run-off. The figures given represent the areas supplied during the period covered by these investigations. There are no complete data available on the rate of increase in the area supplied in past seasons. Such information as could be secured is given in the following discussion. The reports of the IT. S. Census give some comparative data. The report of the irrigation census for Tulare County as a whole is as follows : Item Results for year 1909 Results for year 1919 Ratio of results for 1919 to those for 1909 Area irrigated, acres 265,404 Flowing wells, number 79 Flowing wells, capacity gallons per hour 35,513 Pumped wells, number I 794 Pumped wells, capacity gallons per hour 237.420 Pumping plants, number 739 Pumping plants, capacity gallons per hour 244,318 398,662 23 7,173 4,515 1,776,335 3,758 2,331,179 1.5 5.8 7.5 5.1 9.5 While this data covers Tulare County as a whole it is probable that the relative increase in the Kaweah River areas is similar to that for the whole county. For 1919, the census reports for the Kaweah River area, three flowing wells, 2136 pumped wells with a capacity of 842.000 gallons per minute, and 1734 pumping plants with a general average lift of 41 feet. Simi- lar data segregated by streams was not given for 1909. The total capacity of the pumped wells in 1919 is 1870 second-feet, a rate of flow exceeded by the Kaweah River only during relatively short periods during the year and closely equal to the maximum simultaneous canal diversions of all canals diverting from the Kaweah River. These figures indicate a marked decrease in flowing wells during the ten-year period covered. The area in which artesian wells may be secured is now much smaller than formerly. For pumping wells the data indicates an increase of over 500 per cent in number and of about 58 DEPARTMENT OP PUBLIC WORKS. 800 per cent in capacity. The areas supplied by pumping plants are not given separately for each county. It would appear that the increase in area served by pumps has been about 500 per cent from 1909 to 1919 for the county as a whole. Data given in the report of the California Conservation Commission for 1912 gives the area served by pumping plants in Tulare Countv in 1909 as 37,942 acres and in 1912 as 75,320 acres or an increase of " 100 per cent in this three-year period. The total area served partly or entirely by pumping plants in the parts of the county covered in these investigations for 1921 is 159,200 acres. This figure does not include areas in the northern part of the county supplied from Kings River sources. The figures are not available on which to base an estimate of the relative rate of increase in the different parts of the county since 1912. On the basis of general data, however, it is considered that the ratio of increase on the Kaweah area has been at least as great as for the areas in the southern portion of the county. In the canvass of pumping plants the date of installation was secured. A summary of the relative number of plants for various years follows. The plants canvassed in the main canal area did not include those supplying supplemental pumping to lands under several of the ditches and the data for this area is less complete than for the others. RELATIVE NUMBER OF PUMPING PLANTS OPERATING IN DIFFERENT YEARS IN PER CENT OF THE NUMBER OPERATING IN 1921. Tear Area along foothills above main canal areas Within main canal area On lower portion of Kaweah Delta out- side of canal area 1921 100 93 84 82 81 78 60 100 91 76 64 57 51 15 100 1920 97 1919 90 1918 85 1917 75 1916. 66 1912 30 The ratio of new development since 1912 has been smaller in the area along the foothills than in the other portions of the delta. The increase in the last three years has been largely in areas north of the river. The figures given exclude the area now in the Lindsay-Strathmore Irrigation District. For the outer area the development during the past three years has been less rapid than during the preceding years. The increase in the total area of general crops from 1920 to 1921 was relatively small although much changing of crops on the same areas occurred. The conclusions presented in the proceding table are in general agreement with the statements of pump dealers as to relative number of plants installed in different years. The figures given have been used in estimating the pumping draft in years prior to 1921. WATER RESOURCES OP TULARE COUNTY. 59 Chapter IV. USE OF GROUND WATER IN AREA DEPENDENT ON KAWEAH RIVER RUN-OFF. INTRODUCTION. The study of the use of ground water can be approached in the same manner as a study of the use by surface diversion. The supply avail- able in the case of ground water is the sum of the various elements which contribute to the replenishment of the ground water. The draft by pumping corresponds to the diversion by canals of the surface flow. The accumulated ground water supply is comparable to storage ; if the draft exceeds the incoming supply a decrease in the storage will result and the ground water will fall. A refilling of the ground water storage can only occur when the replenishment exceeds the draft. It is obvious that over a period of years the total inflow must equal the sum of the elements of outflow if the ground water levels are to be maintained. The separate elements involved in a ground water study are more difficult to measure due to their inaccessibility but the principles of supply and use do not differ from those involved in surface irrigation by canals. The study of the use of ground water on the Kaweah River area has been approached by considering the elements of replenishment, the extent of the use or draft by pumping, the probability of escape of ground water by general outward movement and the resulting balance of use and replenishment as indicated by the rise or fall of the ground water. It is not possible to measure the elements of inflow to the ground water on the Kaweah Delta. The records of run-off furnish an ade- quate basis for estimating the total mean annual water supply but the proportion of this which reaches the ground water can not be deter- mined by direct measurement. Seepage from river channels and from canals can be considered as practically all reaching the water table. Measurements of canal seepage can also be made. Total losses from irrigation due to deep percolation can only be approximated at best. The elements of draft also can not be definitely measured. The pumping plants were canvassed and data on the amount of water pumped obtained. Such records while probably fairly dependable as a whole are not accurate as to details and can not be made so without an extent of measurement of the discharge of each plant which is beyond the scope of practical investigation. Fairly complete records of the fluctations 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. The more complete records are those of the Lindsay- Strathmore Irrigation District which have been made available for use in these investigations. In order to cover the full area considered to be dependent on the Kaweah River for such ground water supplies as it might receive additional observations have been made since July, 1920, covering the area as far westerly as Cross Creek. Additional records 60 DEPARTMENT OF PUBLIC WORKS. within the area of the Corcoran Irrigation District were also secured through the cooperation of this district. Sufficient records were obtained westerly from Cross Creek and northward to the Kings River ridge to determine the direction of slope of the ground water in these areas. Data relating to the ground water south and west of Hanford was made available by Mr. Max Enderlein. civil engineer of Hanford. Elements of Inflow or Recharge of Ground Water. The records of canal diversions in 1917 (Table 11) account for practically the entire river flow during the summer months. Similar records more carefully taken in 1020 and 1921 (Tables 12 and 13) indi- cate a channel seepage of about 15 per cent of the run-off. In years of larger total run-off the percentage of seepage from stream channels and overflowed areas will vary with the conditions of run-off. Evidence was presented in the trial of the Tulare District ct al. vs. Lindsay Sir athmore Irrigation District during 1917 on the number of irrigations usually given to lands supplied by the ditches. This data, taken in connection with the average diversions per acre indicate that the average amount of water applied at each irrigation from the canals may be as large as one acre-foot per acre. Such rates of use will result in percolation losses which will reach the ground water. That such losses occur and that they may materially affect ground water levels is indicated by the rise of wells in the vicinity of irrigated areas during the period of irrigation. Estimated Draft on Ground Water. The pumping on the area supplied from Kaweah River was canvassed to secure data on the amount of draft on the ground water. It is not feasible to secure an accurate measurement of such draft due to the large number of plants operating. An accurate measurement of the total amounts pumped would not give the net draft on the ground water as a portion of the pumped water, where the use is excessive, will return to the ground water by percolation. The areas of each crop irrigated by pumping, the number of irriga- tions given and the average depth of each application were used as one basis of estimating the total draft. The periods of operation, the power consumption, the efficiency of the plant and the lift were also used as a basis of estimate. The efficiency of a number of plants was tested to furnish an average efficiency for the different types of plants used. From all of the data obtained estimates of the average use for the dif- ferent crops in the different parts of the area were made which were applied to the areas of each crop. Where both ditch and pumping supplies are used on any area the proportion of the supply secured by pumping was estimated based on the number of irrigations given from each supply and the general char- acter of the water supply and service under each ditch. The areas outside of the main canal areas were canvassed directly for the purposes of these investigations. The areas of supplemental pump- ing for lands served by canals were secured largely from the results of the investigations of the Lindsay-Strathmore Irrigation District. Tests of 53 centrifugal pumping plants resulted in an average over all efficiency for the plants of 38.6 per cent which is ecpiivalent to a WATER RESOURCES OP TULARE COUNTY. 61 power consumption of 2.66 kilowatt hours per acre-foot of water lifted one foot in height. The plants tested were using centrifugal pumps varying in size from two inches to eight inches, the larger proportion being from three to five inches. The efficiency tended to vary somewhat with the size increasing with the larger plants. This tendency was irregular and not large in amount and the average efficiency given was used for plants of this type. The irrigation practice under pumping plants was found to vary for the different portions of the area and for the different crops. Plate V, Figure A. Cross Furrow Irriga- tion of Orchards Near Visalia. Alfalfa is irrigated in border checks 40 to 60 feet in width and 300 to 1200 feet in length, the larger checks being used on the heavier soils. The practice varies from five irrigations per season of an average depth of about 0.7 feet on the more retentive soils to 12 iirigations of an average depth of about 0.3 feet on the heavier soils. The results for 53 farms serving a total area of alfalfa of 4080 acres for which data on the water used was obtained gave an average amount pumped of 3.4 acre-feet per acre. The usual season extends from March to September, inclusive. 62 DEPARTMENT OP PUBLIC WORKS. Plate V, Figure B. Pumping Plant and Concrete Pipe Distribution System for Orchard near Exeter. Corn, such as Egyptian or milo maize, is grown as an independent crop and also following grain. It is given from one to four irrigations, the average being three. The average use on 17 areas totaling 545 acres was found to be 1.25 acre-feet per acre. The practice regarding the irrigation of grain varies with the pre- cipitation for each season. Usually an irrigation is given in the Fall before seeding with an additional irrigation in the Spring. With a large rainfall at either season one or both of these irrigations may be omitted. The average is probably one irrigation per season. On seven areas totaling 516 acres given one irrigation the average amount pumped was 0.7 acre-feet per acre. Cotton and rice were grown to some extent in 1920; the acreage in these crops in 1921 was materially reduced. For cotton an average of about four irrigations of 0.5 acre-feet per acre was typical. The use for the small area in rice was relatively large ; no direct data on the amount used was obtained. For orchards and vines the usual practice in the central and western portions of the Kaweah Delta is to irrigate from one to five times, the larger number of applications being given to the younger trees and vines. Three irrigations, extending from April to September, would be typical of the average practice. Data on twenty orchards and vineyards, totaling 1061 acres, indicated an average depth of pumping of 2.15 acre-feet per acre in this area. For the citrus plantings on the higher lands lying in the vicinity of Exeter and Lindsay and also on the north side of the river, where the heavier soils underlain by hardpan occur, more frequent irrigations are required as only a limited amount of water can be made to enter the soil at each application. Usual practice would be represented by an irrigation each month for six to eight months with an average of WATER RESOURCES OF TULARE COUNTY. 63 seven irrigations. The season of irrigation varies somewhat with the varieties grown; some winter irrigation of Valencias may be practiced if the rainfall is deficient. March to October, inclusive, would repre- sent the general season of use, however. Data on 38 areas in citrus crops, covering 1400 acres, gave an average use of 2.6 acre-feet per acre. The delivery for similar crops on similar soils within the Lindsay-Strathmore Irrigation District has averaged about 1.6 acre-feet per acre. It appears that those owners having pumping plants from which larger supplies may be secured are actually applying to their orchards about 2.5 acre-feet per acre. The figures given represent the estimated total draft on the ground water for the different crops. When pumped, such water is subject to loss by seepage in farm ditches and by percolation through the soil in irrigating. As the average care in handling water under the pumping plants is better than that used in general irrigation from the ditches diverting from the river with a smaller average depth applied at each irrigation the return to the ground water from pumping should be relatively less than the losses from ditch irrigation. For the higher areas of heavier soil very little return to the ground water is probable. For much of the deciduous orchards and vineyards cement pipe is used for distribution with a resulting reduction in conveyance losses. It is not feasible to estimate definitely the proportion of the total draft which may return to the ground water. Under average condi- tions of the use of pumped water a relatively small return would be expected but such average use includes areas on which the use is exces- sive and from which losses will occur. The drafts, as estimated for each crop and area, have been reduced by 10 per cent for the upper areas, 20 per cent for the pumping within the main canal served areas and 15 per cent for the outer areas to give the estimated net draft. These reductions are arbitrary and, while possibly fairly representative of average conditions, will vary materially in individual cases. They are considered to include both percolation losses and any over estimate of the gross draft. The summary of the estimated total net draft is shown in Table 18. The figures given show an estimated total net pumping draft for 1921 of 162,000 acre-feet which was equal to 14 per cent of the run-off of that year and 41 per cent of the mean annual available run-off. The average draft per acre irrigated is smallest in those areas where pump- ing is used to supplement canal use. The pumping by the Lindsay- Strathmore Irrigation District and by small plants within the area served bv the Lakeside Ditch are not included in the figures shown in Table 18. The relatively heavy draft per acre of gross area in the area west of the Lindsay-Strathmore Irrigation District is noticeable in comparison with the draft in the other areas. Possible Sources of Loss from Kaweah Delta Ground Water Storage. The efficiency of the Kaweah Delta as a reservoir for the storage of ground water depends, like any other reservoir either surface or under- 64 DEPARTMENT OP PUBLIC WORKS. TABLE 18. Total Estimated Pumping Draft from Ground Water by Small Pumping Plants in Areas Dependent on Kaweah River for their Ground Water Supply. Acres irrigated Total estimated net draft from ground water, acre-feet Gross area in acres Average draft in acre-feet per acre irrigated Average draft in Area By ditch and pump By pump only acre-feet per acre of gross area Main area of Kaweah Delta covered by canals diverting for lands below Venice Hills Area covered by canals diverting mainly for lands above Venice Hills Area of lower Kaweah Delta outside of areas covered by canals . 18,900 6,900 100 37,400 9,700 14,900 7,300 85,000 27,000 31,000 19,000 190,000 60,000 95,000 20,000 1.5 1.6 2.1 2.6 0.45 0.45 0.30 Area west of Lindsay-Strathmore Irrigation District toward which the ground water slopes from the Kaweah Delta. - 0.85 Totals.. 25,900 69,300 162,000 365,000 1.7 0.45 ground, on its water tightness. If it is a closed basin in which ground water may be retained until withdrawn by pumping, such ground water storage may represent the most effective and economical means of utilizing the available water supply. If it consists of a sloping body of water moving steadily, even if slowly, toward some underground outlet it can not be expected to be efficient in retaining the run-off of years of more than normal supply for use in following seasons of deficient How. An effort has been made to investigate, as thoroughly as the scope of these investigations has permitted, tbe conditions relating to the water tightness of the Kaweah Delta. The general direction and rate of slope of the ground water is shown by the ground water contours on Map 2. The ground water movement is, like other flow, in the direction of the greatest slope which is at right angles to tbe direction of the contours. The general direction of the slope on the Kaweah Delta is toward the southwest. The change in direction of the contours north of Cottonwood Creek as the area served by Kings River is reached indicates the division of the areas dependent on Kaweah and Kings rivers. The contours west of Cross Creek show that the ground water slopes nearly south in this area with the con- tours following the general direction of the margin of Tulare Lake, indicating both a direction of movement toward Tulare Lake instead of to the north and across the lower Kings River Delta and a source of supply from Kings River rather than from Kaweah River. On Map 2 are also shown portions of the contours representing deeper wells which in some instances formerly were artesian or flowing. The water rises in such deeper wells to elevations about 10 feet higher than that in adjacent shallow wells, indicating that the amount of pressure in the deeper wells is in excess of that in the shallow wells. The direction of slope of the deeper ground water closely parallels that of the shallow wells indicating that any movement in such deeper strata will also be toward the southwest rather than toward the northwest along the main San Joaquin Valley trough. WATER RESOURCES OF TULARE COUNTY. 65 Ground Water Conditions Along Kings River Ridge. In addition readings were secured on deeper wells north of the Kings River Ridge. In the vicinity of Riverdale the ground water elevations were found to vary from about 215 to 230 feet with an increase in elevation toward the east along the Kings River Ridge. Surface water on the Kings River Ridge, near Ilardwick. has an elevation of about 240 feet; no deeper wells were found in this vicinity. The water in the deeper wells in the Kaweah Delta vary in elevation from about 250 feet near Tulare to about 200 feet near Corcoran, with the slope definitely to the southwest. The deeper wells north of the Kings River Ridge appear to obtain their supply and pressure from sources of loss along the Kings River and to have a direction of slope similar to that of the surface waters which is both to the north and to the south away from the ridge. The elevation of the water in the deeper wells along Fresno Slough is such that but little, if any, fall would be available to cause movement from the deeper strata on the westerly portions of the Kaweah Delta even if continuous strata existed under the Kings River Ridge through which such movement might take place. The conclusion appears to be warranted that the Kings River Ridge is a barrier to the movement northward of any ground waters originating on the Kaweah Delta and also probably for ground waters originating from any areas south of Kings River. If any ground water movement occurred outward from the Kaweah Delta such water would eventually have to reach an outlet. If such movement is toward the basin of Tulare Lake and does not escape northward it would have to appear within the basin. Tulare Lake is considered to be a sealed area, its lowering when no inflow occurs is at a rate represented by evaporation from its surface, its becoming dry indicates lack of seepage inflow. While water from Kaweah Delta may reach the deeper strata under Tulare Lake, it is considered that it is held there without natural outlet and accumulates pressure until natural relief is obtained through the filling of areas on the delta so that surface losses occur or until artificial relief through wells is secured. Ground Water Fluctuations on Kaweah Delta During Winter Months. During the summer months the fluctuations of the wells represent the combined effect of inflow, draft and possible outflow so that the effect of any one factor can not be distinguished. During the winter months, however, both inflow and draft are at a minimum and the effect of any outflow may be more definitely observed. During the years covered by the well records the winter run-off has been generally smaller than normal so that the effect of any natural outflow of ground waters should be more readily discernible. An examination of the well records indicated that the downward trend, due to late summer pumping, ended generally by November 1. Little use by pumping occurs before February 1. The well records were studied and the fluctuations for each season from November 1 to February 1 computed. The rise or fall of each well for each winter since 1917 was plotted at the location of the well and the average 5—21044 66 DEPARTMENT OP PUBLIC WORKS. fluctuations for each area determined. The resulting' balancing of the amount of rise and fall, together with the stream flow and rainfall, are shown in Table 19. Table 19 indicates a net rise for the area as a whole TABLE 19. Summary of Changes in Ground Water from November 1 to February 1, Expressed in Total Equivalent Soil Volume in Acre-feet of Rise or Fall. Area Main area of Kaweah Delta covered by canals diverting for lands above and below Venice Hills . Area of lower Kaweah Delta outside of areas covered by canals Area west of Lindsay-Strathmore Irrigation District toward which ground water slopes from the Kaweah Delta Total _ Stream flow, Kaweah River, Nov. 1 to Feb. 1. acre-feet Rainfall at Visalia, Nov. 1 to Feb. 1, in inches Nov. 1. 1917 to Feb. 1, 1918 —39,000 2 +20,000 +62,000 +43,000 10,100 0.49 Nov. 1, 1918 to Feb. 1, 1919 1+15.000 2 +20,000 +54,000 +89,000 23,800 3.65 Nov. 1, 1919 to Feb. 1, 1920 —23,000 2+20,000 +57,000 +54,000 17,900 1.98 Nov. 1, 1920 to Feb. 1, 1921 +83,000 +26,000 +69,000 +178,000 34,800 4.66 Nov. 1, 1921 to Feb. 1, 1922 + 74,000 36,550 6.39 'Estimated; well records incomplete for this period. 2 Kstimated; well records for this area began in 1920. during each winter of the period of record. The conclusion appears warranted that there is no movement of ground water outward from the Kaweah Delta as the well fluctuations and use during these months will account for the inflow. During years of light run-off there is a lowering of the ground water in the upper portions of the delta. In both years covered by the actual records there was a rise of the ground water in the lower delta. The ground water contours indicate a total fall of about 100 feet in the ground water elevation from the vicinity of Visalia to the western end of the canal served area. Under the influence of this slope there appears to be a movement of ground water outward from the upper portions of the Kaweah Delta. In years of small winter run-off this outward movement appears to exceed the inflow with a consequent lowering of the ground water in the upper delta. In years of greater run-off the inflow exceeds the outer move- ment and an actual rise of the ground water occurs during the winter months in the upper delta. In all years of record there is an actual rise in the outer areas. The records cover four seasons for the area west of the Lindsay-Strathmore Irrigation District. Only two seasons records are available for the westerly outer area ; both show a rise of the ground water. These were years of larger winter run-off than the three preceding winters. There was less rise in the more westerly wells for which records are available for the winter of 1917-18 than for 1920-21. Somewhat less movement of ground water outward on the delta would be expected in 1917-18 than in 1920-21 as the ground water on the upper delta was lower relative to that on the outer delta with a consecpient flatter slope to the ground water. The data shown in Table 19 have also been plotted in Fig. 5. A fairly consistent relationship between the winter run-off and the WATER RESOURCES OF TULARE COUNTY. 67 SOOOC. S to r lb i 4O000 30000 2OOO0 IOOOO -so coo O so ooo /oo ooo /So ooo doo ooo aso ooo Ctianqe in l/o/ume of Ground Wafer in Acre- feet from November / to February I . Fia.S. ffe/aticn of f/uctuaficns of Ground Wafer m tfaweah De/ta to f?un-off during the Wf/7fe/* Months ground water fluctuations in the main portions of the Kaweah Delta is shown. A winter discharge of about 20,000 aere-feet appears to be required in order to maintain the ground water during the three months on the upper delta. This discharge would not all reach the .•ground water due to diversion for winter irrigation. There would also be some winter draft by pumping which might amount to 8000 to 10,000 acre-feet. The rise of the ground water in the area west of the Lindsay- Strathmore Irrigation District appears to be independent of the winter flow in the Kaweah River. Such movement occurs under the general influence of the ground water slope from the adjacent area within the areas covered by canals and the extent of variation of such slope in years of different amounts of run-off does not appear to materially affect the amount of such movement. The data available for the western area of the lower Kaweah Delta do not cover a sufficient period to enable a similar relation to be plotted on Fig. 5. The rise in the outer area during the winter of 1921-22 was greater than during the winter of 1920-21. The run-off was similar in the two seasons. The rainfall was heavier in the second season and may have resulted in some direct additions to the ground water as it came in well concentrated storms. For the entire Kaweah area the total fluctuations appear to vary fairly consistently with the run-off. The curve shown on Fig. 5 is subject to the uncertainty involved in the estimated fluctuations of the lower delta for the seasons for which direct records are not available. 68 DEPARTMENT OF PUBLIC WORKS. If any movement of ground water occurred from the Kaweah area into other areas it would be expected that in order to balance the inflow and draft an item covering the amount of such outflow would be required. In a period of no inflow a lowering of the ground water proportional to the amount of such outflow would be expected. The data given in Table 19 and Fig. 5 indicate that even in winters of low run-off such as 1917-18 there is a net rise of the ground water. The curve for the whole area when extended indicates that even with no run-off there would be no lowering of the ground water over the area as a w r hole. If such outward ground water movement does not occur during the winter months it would not occur at other seasons of the year. The data available on the ground water fluctuations appears to agree with the conclusions previously given based on the discussion of the ground water contours that there is no indication of the occurrence of any such outward ground water movement. Formation of Kaweah Delta. A further effort was made to trace any possible outward ground water movement by a study of the materials encountered in the drilling of wells. This consisted both of the collection of actual logs of wells •where available and of discussion of general conditions with those engaged in well drilling. The conditions under which the various materials forming the Kaweah Delta have been deposited are too com- plex to enable any definite structure to be developed from such data. In general the first artesian strata is found after passing through a layer of blue clay at depths which vary from about 350 feet near Tulare to 500 feet at points five or six miles further west. Below these depths alternating strata, of sands and blue clays are found. The slope of the upper blue clay strata is somewhat steeper than that of the present ground surface. These strata may have some relationship to the clays occurring in the hog wallow areas near the upper edge of the valley, the difference in color being due to differences in conditions affecting oxidation. A well in the courthouse yard at Visalia is reported to have struck a tight red and yellow clay at a depth of 275 feet. Present stream channels in the upper portion of the valley area are cut down into the underlying heavier formation and afford a means of access of water to any pervious strata of such formations. The depths given to the first heavy clay strata may indicate the thickness of the recent valley alluvium or delta deposits. There is no difficulty in securing ground water supplies from wells anywhere in the main areas of the Kaweah Delta and the wells are usually relatively shallow, few exceeding 200 feet in depth. In the outer portions of the delta the water bearing strata are less frequent and deeper. West of a line approximately following the Santa Fe Railroad from Corcoran to Hanford, the yield of shallow wells is small and deeper wells, usually artesian, are used. It appears that the upper water bearing strata tend to pinch out in this area and the only avail- able supplies are from the lower areas containing water under artesian pressure. Flowing wells could formerly be obtained over a much larger area than at present; some wells flow only during the winter season now that formerly flowed continuously. The source of the "WATER RESOURCES OF TULARE COUNTY. 69 water in these deeper strata appears to be the Kaweah Delta until the general body of underground water underlying the valley trough is reached where the source may be the mingled supply from all streams tributary to the Tulare Lake Basin. In Water Supply Paper 398 of the U. S. Geological Survey the quality of the water obtained from different depths in wells in this vicinity is discussed with conclusions that appear to agree with the general statements made above. Wells in the areas formerly covered by Tulare Lake, where the formations consist of deposits from the lake including the saline deposits due to evaporation, are stated to yield Avater high in sulphates. Those deeper wells in the same areas which draw their supply from sediments derived from the east side streams and deposited under the lake bed fill secure water of good quality. The eastern boundary of the area affected by lake residues is shown as running from Earlimart through Angiola, Corcoran, Guernsey and Lcmoore. Data given regarding the depth of the lake deposits result in the conclusions that the thickness varies from a negligible amount near Corcoran and Guernsey to 400 feet or more at a distance of six to eight miles west of Corcoran. The conclusion is also reached that ground waters from the east and the west side sources do not mingle to any large extent and that wells to the west of the middle of the lake would probably encounter the sulphate waters derived from west side sources at all depths. The lake bed deposits being of generally finer materials than those deposited by the streams in building up their deltas are less freely water yielding and the difference in both quality and quantity account for the use of deeper wells in the area where the lake bed fills overlap the direct stream deposits. This difference in the conditions under which the materials have been deposited appears to account for the differences in wells in this area. The abruptness of the change in the conditions affecting surface wells has caused the line of change to be referred to locally as being a possible "fault line." Apparently no such assumption is needed to explain the conditions existing here. The data available on the character of the formations and the quality of the water obtained appear to still further support the conclusion that no general outward movement of ground water from the Kaweah Delta occurs. The tightening of the surface strata on the western portion of the delta would limit, if not entirely prevent, any such movement in these strata. The change in quality of the water in the deeper strata indicates that movement of the sulphate free water from the Kaweah Delta has not progressed beyond the areas adjacent to the delta. GROUND WATER FLUCTUATIONS. The general ground water fluctuations for any period indicate the balance between the elements of replenishments and of draft for that period. The data on ground water from which the fluctuations can be studied on the Kaweah area consists of records beginning early in 1917 over the upper and main canal areas and maintained to date by parties to the pending litigation resulting from the pumping by the Lindsay- Strathmore Irrigation District, data given in Water Supply Paper 70 DEPARTMENT OF PUBLIC WORKS. 398 of the U. S. Geological Survey on depths to ground water in 1905, general information on conditions in past years and records extending over the outer portions of the Kaweah Delta from July, 1920, to February, 1922, secured in the course of these investigations. The records of the Lindsay-Strathmore Irrigation District have been used for the areas covered. Those pertaining to the area immediately adjacent to the area of pumping by the district have not been included in the discussion which follows. Ground Water Fluctuations 1917 to 1921. The records of wells indicate that the lowering due to pumping ceases in the late fall and that a rise due to the lessening of draft and the recharge begins. A study of the well records indicated that this change in the ground water elevations occurs generally about November 1 and this date has been used as the division of the ground water year. As the records did not begin until early in 1917 a separate year from March 1, 1917. to March 1. 1918, is used for that season. These well readings cover all of the Kaweah Delta except the outer portion on the west and southwest. The records of about 200 wells were available for each of the years. About 80 wells were observed for the outer area of the delta in these investigations from July, 1920, to February, 1922. The probable fluctuation of these wells for the other years was estimated by comparison with adjacent wells for which records covering long periods were available. The change of elevation in each well for each year was plotted on maps showing the location of each well and contours showing equal changes of rise or fall were drawn from which the average changes shown in Table 20 were determined. Map '3 gives the results for 1920-21. TABLE 20. Summary of Average Lowering of Ground Water, in Feet, in Kaweah Delta Areas, 1917 to 1921. • Average lowering for period in feet Area Mar., 1917 Nov. 1, 1917 Nov. 1, 1918 Nov. 1, 1919 Nov. 1, 1920 Nov. 1,1917 to to to to to to Mar., 1918 Nov. 1, 1918 Nov. 1, 1919 Nov. 1, 1920 Nov. 1, 1921 Nov. 1, 1921 Main area of Kaweah Delta cov- ered by canals diverting for lands below Venice Hills. _ 2.5 2.5 2.1 1 0.8 5 5 Areas covered bv canals diverting for lands mainly above Venice Hills 0.8 9 9 0.2 8 2.8 Area of lower Kaweah Delta out- side of areas covered bv canals_ *2.3 *3.2 *2.7 •1.3 1.8 9.0 Area west of Lindsav-Strathmore Irrigation District toward which ground water slopes from the Kaweah Delta .. 1.5 2.2 2 1 0.8 13 6.4 Mean. _ ... __ 1.9 2.2 2.0 0.4 1.0 5.6 Total run-off of Kaweah River — acre-feet... 391,500 237,000 281,500 377,500 373,500 317,500 Estimated total pumping draft — acre-feet 109,000 5.21 124,000 8.07 133,000 8.85 142,000 9.32 162,000 8.56 *Estimated. WATER RESOURCES OF TULARE COUNTY. 71 The summations of the lowering of the water table in different years are not altogether consistent. It would be expected that the total low- ering would be greatest in years of least rainfall and run-off and of greatest draft, The results in general vary with the amount of run-off except for 1920 when the lowering was less than that in 1921 although the run-off in the two years was practically the same. Although the total run-off in 1920 and in 1921 was closely the same, its distribution by months differed. In 1920, 50 per cent of the run-off occurred in May and June and 7 per cent during November to February inclusive. In 1921, the run-off was more evenly distributed; only 28 per cent occurred during May and June and 16 per cent in November to February. The more even run-off in 1921 resulted to some extent in a larger proportion of the supply being diverted by the older ditches for areas near the upper portion of the delta with less water reaching the outer canal areas. In 1920 the rainfall in the area was somewhat greater than in 1921. In March, 1920, the rainfall was 3.74 inches at Visalia and in March, 1921. 1.36 inches with some resulting earlier pumping in 1921 than in 1920. In the early part of 1920 there were some restrictions placed on power for pumping due to the shortage of supply which had some effect in lessening the draft at that time. For the mean of 1920 and 1921 with a net available water supply of 369,000 acre-feet per year an area of 183,500 acres of cropped or sub- irrigated land was supplied with a resulting average lowering of the ground water of 0.7 feet over an area of 365,000 acres or a total drain- ing of 255,000 acre-feet of soil volume. If the ground water had remained stationary a net average use of about 2.0 acre-feet per acre would have been indicated. The lowering is difficult to estimate as the quantities of water represented by changes in ground water elevations are variable. If the loss in ground water storage due to the lowering is estimated to represent an average of one-tenth of the volume of the soil drained, a ground water depletion of 25,000 acre-feet is indicated. The mean annual gross run-off of the Kaweah River has been estimated to be 451,000 acre-feet of which an average of 55,000 acre- feet is not retained on the Kaweah Delta, leaving an average net avail- able supply of 396.000 acre-feet. The difference between the net available supply in 1920 and 1921 and the mean is 27,000 acre-feet. The above comparisons indicate that the present draft on the Kaweah River run-off is closely equal to the mean annual net available supply. An increase in use under existing conditions would be expected to result in a lowering of the average ground water elevations. The conclusion that present use is about equal to the available supply does not mean that all of the present use can be maintained without further lowering of the ground water as the supply and use in the different portions of the area are not balanced. In some portions due to canal diversions and light pumping the ground water has risen since the deficient years of 1918 and 1919, in other areas of small canal use or heavy pumping there has been a continual lowering of the ground water which can only be expected to continue even in years of large run-off under existing conditions of diversion. The conditions affecting the different portions of the area are discussed in detail later. 72 DEPARTMENT OF PUBLIC WORKS. Change in Ground Water Since 1905. In Water Supply Paper 398 of the U. S. Geological Survey, Ground Water in the San Joaquin Valley, California." reading's of wells in Tulare County with the owner's name, the section, township and range of the location and the depth of water are given. The report states that the records were obtained during - the period from 1905 to 1907 ; the work in Tulare County is referred to as of 1905. While the seasons of 1901 and 1905 were somewhat below normal in run-off, the pumping draft on the outer portion of the delta was relatively small at that time and the water table was probably relatively high. An effort was made to find the wells read in 1905 in order to deter- mine the changes in ground water elevation since that year. Such comparisons were made for 97 wells scattered from the vicinity of Visalia to the area which was artesian in 1905. The readings were secured in 1920. The comparisons have been reduced to the changes from 1905 to 1917 by comparison with the well records for the same areas for the period 1917 to 1920. The results are as follows : Area Number of wills found Average lowering, 1905 to 1917 Average lowering, 1917 to 1921 T. 18 S., R.s 23 and 24 E.. in vicinity of Visalia__ T. 19 S., R.s 23-25 E., extending from Visalia to Tnlare __ . 31 33 DO 4.0 1.3 3 1.1 7.0 T. 20 S., R.s 23 to 25 E., extending from Tulare toward Corcoran __ 10.8 The first group of wells are located generally within the canal served area and show more drop from 1905 to 1917 than for the period 1.917 to 1921. In the second area the canal service is less extensive and more irregular in amount with a consequent larger development of pumping draft in recent years. This is indicated by the drop of 7.0 feet in the last four years as compared to 1.3 feet for the previous twelve years. For the third area there is little canal service and pumping began relatively somewhat earlier; however, the drop per year lias been about ten times as large for the past four years as for the previous ten years. Not all of this difference should be considered to be due to the relative draft during the two periods as the last four yen's have been ones of less than average run-off. Variations in Conditions of Water Supply and Use in Different Parts of Kaweah Delta. The available data regarding water supply, diversions, areas served. pumping draft and ground water fluctuations for the Kaweah Delta as a whole has been presented and discussed with the conclusion that for the total area of the Kaweah Delta the present rate of water con- sumption very closely equals the mean annual net available water supply or that the present total irrigation development is as large as can be maintained with the water supply under existing conditions without a continuous lowering of the ground water in some parts of the delta WATER RESOURCES OF TULARE COUNTY. 73 over any period of years. This conclusion is limited to present condi- tions existing in this area both as to the amount of the net available annual water supply and the character of its use. It has also been concluded that while the above condition is correct as an average for the area as a whole, present development is not distributed over the delta in proportion to the locally available sources of water supply and that continued and serious lowering of the ground water is occurring and can only be expected to continue to occur in certain portions of the area if present conditions are maintained. There is frequent discussion of the relative advantages of position in securing a permanent ground water supply between those located near the upper end of a delta as compared with those located at the lower or outer edges. The ground water occurs in the delta on a slope from the upper end outward to the lower edges and the argument is advanced that as pumping becomes heavy the ground water in storage in the delta will tend to become depleted and consequently to assume a flatter slope with a greater lowering at the upper end of the delta than at the outer. This would result in a more rapid increase in the lift on the upper end with a more quickly felt necessity of reducing pumping due to increases in costs. This basis of reasoning has not been supported by the experi- ence on the delta of Kaweah River to date. The maximum lowering 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 w r here replenish- ment mainly occurs by percolation from the stream channel and canal use have maintained their ground water levels. A similar advantage in position appears to be inherent to such locations near the source of the ground water supply that exists on a canal where those located near the head of the canal have a material advantage in securing water in times of scarcity over those on the lower portion. Should a flattening of the ground water slope in the Kaweah Delta occur due to a large lowering of the ground water in the upper portion of the delta the amount of ground water reaching the outer portions would be reduced as both the area of cross section and the slope under which such movement occurred would be reduced. The lowering of the ground water around the edges of the Kaweah Delta is resulting in increasing the ground water slope toward those areas and some increase in the ground water movement is to be expected. It is extremely doubtful, however, if such increased ground water move- ment will be sufficient to furnish the supply now being drawn from at least some of these outer areas until the total increase in lift has become so great that pumping will be restricted by the resulting costs. The present total fall of the ground water from the upper end of the delta 10 Goshen, Tulare or Lindsay is about 100 feet. The velocity of ground water is generally considered to vary about directly with the slope. To double the velocity would recpiire that the slope or fall be doubled or a lowering of the ground water of 100 feet at the points mentioned would probably be required before double the present ground water movement to these outer areas might be expected to take place. The conditions in the separate portions of the general areas previously discussed vary. The following discussion presents the conclusions 74 DEPARTMENT OF PUBLIC WORKS. reached in these investigations for the local areas within the general divisions of the delta. Main Area Covered by Canals. On Map 1 the areas served by the larger number of the Kaweah ditches are shown. On Map 3 the net ground water fluctuations for 1920-1921 are given. The area served by those ditches having generally the earlier priority of right to the use of Kaweah River has main- tained its ground water elevations during the past two years of some- what less than normal run-off. There was an area of 135,000 acres covering the lands within which the 1921 canal irrigation on the delta was applied, out of the total area of 190,000 acres previously classed as the general area within which canal irrigation may be applied, for which the ground water averaged in 1921 to remain at the same elevation, the local rises balancing other local lowering. The pumping draft in this area averaged 0.3 acre-feet per acre of gross area. For the conditions existing in 1921 the inflow to the ground water balanced the rate of local pumping draft and the ground water movement into the outer parts of the delta. In the same area in 1919-20 there was an average rise of the ground water of 0.25 feet. For the period of 1917-1921 the portion of the area in the vicinity of Visalia has had no ground water lowering; about one-half of the area has lowered less than two feet and the outer portions have lowered as much as five feet. This area includes the areas north of the St. Johns River served by the Matthews and Uphill ditches and in gen- eral the area between St. Johns River and the eastern boundary of the lands served by the Peoples Ditch and extending to the southwest to about the line of the Southern Pacific Railroad from Tulare to Goshen. There was in general some rise in the ground water in the upper por- tions of this area in 1921 and some lowering in the lower portions. In this area there were 13,700 acres reported as receiving canal service only, 11,800 acres receiving both ditch and pump service, and 11,500 acres receiving pumped water only, a total area of 73,000 acres or slightly over 40 per cent of the total irrigated area dependent on Kaweah River. The run-off in 1920-21 was 93 per cent of the estimated mean annual net available supply under existing conditions, the actual shortage being 27,000 acre-feet, With present conditions of use it would appear that this area can be expected to maintain its ground water elevations with some lowering in dry years and recovery in excess years. An increase in pumping draft particularly at the upper end of this area would not be expected to result in material ground water lowering within the area itself but will serve to intercept some ground waters now moving to the outer areas and increase the rate of lowering there. Due to the high ground water in some parts of the upper area there is now loss of moisture from subirrigated areas in excess of beneficial needs. Aji increase in draft in these areas with a lowering of the ground water would result in the salvage of such losses. To maintain not only the average ground water elevation over this area as a whole but also in its parts, the distribution of a larger pro- portion of the run-off for surface irrigation in the areas more distant from the river than occurred in 1921 will be required. Such increase in WATER RESOURCES OP TULARE COUNTY. 75 canal use in the outer areas would serve both to reduce the draft and to increase the replenishment in those local areas. The remaining 55,000 acres of the area previously classed as the main canal served area lying west of the Southern Pacific Railroad and extending from Goshen to the Tule River has been included in the main canal area as shown on Map 2 due to the fact that in years of excess run-off portions of this area may receive canal service principally from the Packwood, Tulare Irrigation District and Elk Bayou systems. In 1920 and 1921 the lands irrigated in this area were relatively small. The ground lowered over all of this area, the amounts being in gen- eral proportion to the extent of the local draft. The average lowering was 2.6 feet with a maximum lowering of about five feet. For the period 1917 to 1921 the total lowering has varied from five to twenty feet being largest in the area of heavy pumping west of Tulare. In the eastern half of T. 20 S., R. 23 E. in which there was very little canal irrigation in 1921 but where the pumping draft averaged 1.3 acre-feet per acre of gross area there was an average lowering of four feet for the year. The rate of draft is four times the average rate for the area which held its ground water elevations in 1920-21. This heavy rate of draft without direct canal irrigation within the area can only be expected to result in a relatively rapid lowering of the ground water. The diversion of larger amounts of canal water into this area or the lessening of the draft by more careful use of the water pumped will be required if the present development is to be maintained. In the western portions T. 20 S., R. 24 E. not included in the canal area maintaining its ground water in 1921, there was an average draft of 0.8 acre-feet per acre of gross area and an average lowering of 2.6 feet in the ground water. Conditions in this area differ from those in the eastern part of T. 20 S., R. 23 E. only in degree. The average pumping draft is somewhat less and the canal irrigation slightly greater with a consequent less lowering of the ground water. The bal- ance for 1921 is a material lowering however, and present development can only be maintained without permanent ground water lowering by the use of larger amounts of canal irrigation than have been used in recent years. The permanence of present rates of pumping in this area will depend on the extent to which canal water may be brought into this area in years of more than normal run-off. In the southwestern part of T. 19 S., R. 24 E. an average draft of 0.6 acre-feet per acre of gross area resulted in an average ground water lowering of 2.7 feet in 1921. In the southeastern part of T. 19 S., R. 24 E. where some canal irrigation was received an average draft of 0.9 acre-feet per acre of gross area resulted in an average lowering of 0.7 feet in 1921. Since 1917 the average lowering in the southwestern part of this township has been about 15 feet as compared with 10 feet in the southeastern portion. These differences illustrate the effect of the addi- tional canal use in tin 1 southeastern part of the township where a heavier draft is maintained with less lowering than in the adjacent southwestern portion. The differences in the conditions of draft and replenishment in the different parts of these areas is further illustrated by the hydrographs of typical wells shown in Figs. 6 to 8. The location of each well is shown on Map 2. 76 DEPARTMENT OF PUBLIC WORKS. The character of the fluctuation of ground water at any point reflects the conditions affecting- the well. The wells used are ones which are not subject to heavy draft and consequently reflect average changes for the vicinity rather than the local effects of single plants. A well whose hydrograph shows little change during the year in general indicates a limited recharge or a location at considerable distance from any direct source of supply. Wells adjacent to streams or canal use generally show a marked rise at the period of flow in such channels or of use under the canal. A lowering during the later season when run-off has diminished and the draft is a maximum is to be expected. S 5 3€5 jeo 355 JSO Jan Feb Mar Apr May Jan July Aug Sept Oct Nov Dec One mile west of Exeter /n area regular cane// ^service. \ \ receiving 3J5~ 33C 325 32o ■4- miles along Oaf side CreeK from Wel/SJ/ /n area x rece/t^/n tr-H" "\ Well 140 A r -' as /eJ £ £ ?' JS 3 . — - • a ~> Two miles east of Visalia Two rn//es south of Ms alia 1 i i i i i . i l :ss -o»it» Two miles north e &sf of Tufa re - ffi/xed C ana/ service and pumping At we s fern edge of canal area heavy pumping - no canal irrigation 3ince fst7 I s: o S30 ess eeo Western limit of canal arte 1 1 mi fed canal seryice\ 1/ ml ted canal irrigation and heovf pumping ^tWTTI^^H Near- Crcjj Cr y.'cii R4i_ ^o5 sit . 2 TO 4 >- w ell 1 1313 1 ?eo __^ 9 pss sse -* I3i ^ "•" 23 ST_ — -i IS _ At Tulare &?• Weil A6 Lk. Deep trve/l- foca/ conditions similar tc jfiatloir tretl fTZiA Deep use It - "V £L local condition s similar fo Jna/fow we// fT33 ~r Well AS^ T /v^. 7. ftydrographs of Typical Wei Is /n lines rad/af/ng across ftaweah Delia along Deep and F^ach wood CreeHs. WATER RESOURCES OF TULARE COUNTY. 79 In Fig. 7 wells 519 to 1912 are located along the general direction of Deep Creek. Well 519 is located in the upper portion of the delta and shows the effect of local stream flow and irrigation. This well in 1921 had practically recovered the 1917 elevations. Well 1629 is also within the canal areas receiving regular service and has recovered since 1919. Well 1625 is located two miles northeast of Tulare in an area receiving irregular canal service and of fairly heavy pumping. A marked lowering from 1917 to 1919 is shown with very small changes since 1919. Well 1708 is located west of Tulare in an area of heavy pumping where no canal service has been received since 1917. The quick response to irrigation in 1917 and the continual lowering since 1917 are noticeable in this well. Unless water for irrigation from canals is brought to this area with fair regularity a continual lowering is to be anticipated. Well 1952 is located about one-half way between Tulare and Cor- coran in an area considered within the. main Kaweah Delta but where very little canal service is received. A marked and continuous lower- ing is shown. Well R32 is located outside the canal area in the lower delta and shows a steady lowering due to pumping. Well 1912 is located at Tulare and like well 1708 reflects the effect of canal irrigation in 1917 and the lack of such replenishment since 1917. Well 1402 in Fig. 7 is located two miles east of Visalia near Packwood Creek. It has nearly maintained the 1917 elevation due to its location in the area of regular canal irrigation. Well 1633 is located two miles south of Visalia under conditions similar to well 1402 except that adjacent canal irrigation is not as extensive. Well 1732 is located font- miles west of well 1633 at the western edge of canal irrigation. The lowering in the two dry years of 1918 and 1919 is noticeable. Since 1919 the replenishment has balanced the draft. There is an area of heavy pumping to the west of this well. Well 1706 is located in the area of the Packwood Canal where canal service has been very limited since 1917 and where pumping is heavy. An average drop of about four feet per year is shown. Well R18 is located at the west limit of the area which is understood to ever receive canal irrigation and where no canal water has been used since prior to 1920. A continual drop with no recoverv is shown. 80 DEPARTMENT OF PUBLIC WORKS. J F ft A MJJASO/VD 30S 300 215 210 26S 2es 260 24s 3 miles west of Vis alia ha Jew welt in Corcoran Imp at/on D /strict. \ rig S. /iy droa raph^ of Ty/o/ca/ . lA/e//%> A M . J J A 5 ° N D . I o v. Jto j/s j/c JOS Joe w\ // to 14 & ■y- »/ /Vor/t; of X> "*"•*> A V Strafhrnore /n area of /oca/ ^ -/ pc/rn p*1(M t00. For the service secured from such storage, this develop- ment is considered less desirable than the previous estimate using 50,000 acre-feet of storage capacity. A smaller supply, such as 20,000 acre-feet per year with 15.000 acre- feet of storage capacity, could he secured with few shortages. The summary for such a supply is also iriven in Table 29. In four years out of the eighteen years of record there would have been shortages in the supply of 25 per cent. The estimated cost of 15.000 acre-feet of storage at the Ward site is $1,400,000 or over $90 per acre-foot. The cost of storage plus the costs of canals would make the cost of securing such a water supply higher than present standards would ordinarily justify. The present development of the Lindsay-Strathmore Irrigation District utilizes storage in a ground water basin along the river channel. The water considered available for storage from the winter and flood flow, as given in Table 29. should be reduced by the amounts of such flow that may be used to replace the water pumped by the district from the basin now used. Storage of Winter Flow Only. The amounts of discharge of the Kaweah River for November to February, inclusive, are shown in Table 29. If rights to the storage of this flow could be secured a minimum of 18.000 acre-feet per year would be available with 18,000 acre-feet of storage capacity. With 35,000 acre-feet of storage capacity a supply of 35,000 acre-feet could be made available in fifteen years out of the eighteen years of record. With 45.000 acre-feet of storage capacity a supply of 45,000 acre-feet could be secured in thirteen years out of eighteen, the shortage in the five years averaging about 40 per cent of the supply. This storage would be equally useful whether obtained at the Ward site or in ground water basins, the differences being matters of cost. A reservoir used for the storage of winter flow would be partly emptied by the time of the main stream flow in May and June and in many years additional use could be secured both by direct diversion and by refilling of storage from such excess flow. A total storage capacity of 50,000 acre-feet for storage under such conditions would appear warranted. If all of such storage should be obtained at the Ward site the estimated cost would be $3,600,000. Storage of Flood Flow Only. The use of a part of the water now passing across the Kaweah Delta by its retention in storage might be feasible without the additional storage of winter flow if it should be found that the existing uses of such winter flow presented legal difficulties not readily adjusted. The 108 DEPARTMENT OF PUBLIC WORKS. water supply available for such storage in each year has been taken as the outflow as given in Table 10. The use that might be obtained from such outflow is .shown in Table 30. TABLE 30. Regulated Irrigation Supplies Obtainable on Kaweah River from Storage of Water Not Now Retained on Kaweah Delta. Estimated outflow from Kaweah River, acre-feet Supply of 20,000 acre-feet supported by 30,000 acre-feet of storage capacity Supply of 30,000 acre-feet supported by 50,000 acre-feet of storage capacity lear Used directly, acre feet Secured from storage, acre-feet Shortage in supply, acre-feet Unused flow, acre-feet Used directly, acre-feet Secured from storage, acre-feet Shortage in supply, acre-feet Unused flow 1903-04 2S.000 2,000 550,000 80,000 255,000 56,000 4,000 33,000 14,000 234,000 27.000 9,000 5,000 4 000 2 000 13,000 13,000 11,000 8,000 4,000 4,000 9,000 13,000 6,000 6,000 4,000 16,000 8,000 7,000 7,000 20,000 9,000 20,000 12,000 16,000 6,000 16 000 11.000 7,000 14,000 16,000 3.000 1,000 10,000 14,000 4,000 20.000 11,000 15,000 507,000 60,000 217,000 19,000 198.000 14,000 6.000 2,000 20,000 20,000 16,000 12,000 4,000 6,000 12.000 20,000 9,000 9,000 5,000 22,000 10,000 10,000 30,000 14,000 30.000 18,000 26,000 6,000 24,000 5,000 10,000 21,000 29.000 2.000 28,000 24,000 13,000 1,000 30,000 21,000 25,000 1904-05 1905-06 480,000 50,000 1900-07 1907-08 1908-09 199,000 o 1909-10... 1910-11 o 1911-12 o 1912-13 o 1913-14 o 1914-15 o 1915-16... 164 000 1916-17 8 000 1917-18 1918-19.. 1919-20 1920-21 Mean 72,000 . 5,500 10,500 4,000 56,000 8,000 14,000 9,000 50 000 Table 30 indicates that with 30,000 acre-feet of storage capacity a regulated supply of 20,000 acre-feet per year might be obtained with an average shortage of 20 per cent ; the shortages occurring in six years out of the eighteen years of record. Four of the years giving shortages are the years 1918 to 1921 ; in 1919 there would have been no water obtain- able. Additional storage capacity would have been used only three times in the eighteen years. The estimated cost of storage would have been $2,500,000 or $125 per acre-foot of the supply it was attempted to maintain. Table 30 also gives the use that could have been secured from 50,000 acre-feet of storage capacity used to support a regulated draft of 30,000 acre-feet.- The average shortage would have been 25 per cent. Shortages exceeding 40 per cent of the supply would have occurred in six years out of eighteen; of these six years three are con- secutive from 1919 to 1921. The estimated cost of the 50,000 acre-feet of storage capacity is $3,600,000 or $120 per acre-foot of supply it is attempted to maintain. Additional storage would have been useful only three times during the eighteen years of record. The construction of 30,000 acre-feet additional storage capacity at an estimated increase in cost of $1,200,000 would have given an average use of 5000 acre-feet per year at an estimated construction cost of $240 per acre-foot of mean annual use for such increased capacity. WATER RESOURCES OF TULARE COUNTY. 109 Chapter VI. POSSIBLE CHANGES IN USE OF RUN-OFF OF KAWEAH RIVER. In the preceding chapters the extent of the Kaweah River water supply, the extent and effect of present use and the results to he antici- pated in the different portions of the area dependent on Kaweah River have been discussed. The conclusion is expressed that the present net use of water for the whole area closely equals the net available supply but that under existing conditions the available supply is not dis- tributed to the different parts of the area in proportion to the present rates of use with the result that shortages in supply now exist in some areas. In the present chapter possible met bods of changing the use of the available water supply so as to give a more efficient use are considered. TABLE 31. Summary of Present Irrigation and its Effect on the Ground Water in the Kaweah Delta in 1921. Area Gross area, acres Area irrigated, acres Average lowering of ground water, feet Draft in acre-feet per acre of gross area Portion of main area receiving canal service in which ground water held its elevation in 1921 _. _ __ _ Remainder of delta area covered by canals _ 135,000 55,000 60,000 95,000 20,000 73,000 30,300 19,300 15,900 7,300 2.6 .8 1.8' 1.3 0.3 1.3 Area covered by canals diverting for lands mainly above Venice Hills __ Area of lower Kaweah Delta outside of areas covered by canals _ Area west of Lindsay-Strathmore Irrigation District toward which ground water slopes from the Kaweah Delta 0.45 0.3 0.85 Total areas. 365,000 145,800 1.0 0.45 Table 31 shows the results of conditions of use on the Kaweah Delta in 1921. The water supply for 1921 was 93 per cent of the mean net annual available supply under existing conditions. The larger part of the run-off was received within a gross area of 135,000 acres either by canal diversion or by stream channel percolation. This area contained about one-half of the land irrigated and held its ground water elevation for the year. The other areas containing the remaining one-half of the irrigation on the delta all show a lowering of the ground water in pro- portion to their use or distance from direct sources of ground water supply. The results presented should be convincing that some modifica- tion of present conditions of use must occur if a continual lowering of the ground water over many parts of the Kaweah Delta is to be avoided. Should such lowering continue it must eventually result in an increase in the pumping cost to a point where pumping will no longer be profitable. The time before such a condition may be reached will depend on the rate of lowering and the increase in lift which present returns can meet. In some areas of relatively slow rate of lowering such conditions may not be reached for a considerable number of years ; in other areas of relatively rapid rate of lowering critical conditions if present ground water conditions continue, will be reached in a rela- 110 DEPARTMENT OF PUBLIC WORKS. tively short period. Further additions to the area irrigated by pumps iu those areas now showing a lowering of the ground water can only serve to shorten the period until such critical conditions may be reached. There are two general conditions under which additional supply may be secured for those areas now having an overdraft on their ground water supply. One of these would consist in such modifications as might be made in present conditions without materially disturbing the present character of practice, the other would be changes that would require the substitution of new practices materially affecting at least a part of the present methods. Among the changes which would not require material modifications in the present general methods of diversion from the stream would be the improvement by lining or otherwise of canals now diverting from the Kavveah River so as to reduce seepage losses in the areas adjacent to the stream and already containing an excess of ground water. Such changes would be mainly of direct benefit to the canals serving areas further from the stream, such as the Tulare Irrigation District, and the Packwood Ditch. The reduction in seepage on such systems would increase the supply which could be delivered to the outer canal areas with benefit both from the additional irrigation secured and from the replenishment of the ground water. An improvement in delivery to the advantage of those using water from canals would result from a more definite scheduling of diversion with rotation between the smaller ditches. This would reduce seepage losses in canals and channels and supply larger deliveries for more effective use in irrigation. in connection with any improvements for canals now serving areas where the ground water is lowering some increase in existing canal capacities would also be desirable. The existing canals have been developed to utilize unregulated stream flow and presumably have been extended to a total capacity which on the basis of the values at the time of construction was economically profitable. Any increase in diversion capacities could divert water for only limited periods during normal years and for very short periods in years of less than normal run-off. With the present values in these areas some additional diver- sion capacity over that of the original construction should be feasible. The benefits of such increased diversion capacity would apply mainly to canals on the lower portion of the delta where the soil conditions are such that direct replenishment of the ground water will occur from such increased canal use. In the higher areas of close textured soil, short periods of canal use while of benefit by reducing the pumping draft during such periods would not result in material additions to the ground water by percolation. The present development has been found to be equal to one acre irrigated for each 2.2 acre-feet of mean annual net available supply. This represents a relatively high rate of development. While some reduction in use might be secured by reduction in the area of crops of larger water use such as alfalfa and a substitution of such crops as orchards, a change which has been in progress in recent years, the total decrease in water consumption to be expected by this method is not large. Alfalfa and wild pasture represent less than one-half of the area now irrigated on the Kaweah Delta. WATER RESOURCES OF TULARE COUNTY. Ill The areas not producing crops on which there may be loss by evaporation clue to high ground water represent about 5 per cent of the cropped area. Changes in the distribution of canal diversion and local pumping which would reduce such losses are desirable. It will not be feasible to reduce losses from this source entirely ; there will necessarily be some areas of high ground water adjacent to the stream channels. The increase in the net available supply by the construction of storage to retain excess flood flows only has been discussed. The costs of storage for such flood water only were shown to be relatively high. Such shortage would not result in injury or interferenc with existing rights as only the run-off in excess of existing rights would be stored. It would, however, recpiire a determination of the extent of existing rights. Due to the high costs involved, other methods of utilizing portions of the excess flow now occurring by increased canal capacity and by lowering of ground water adjacent to the channels so as to increase absorption of flood flow are thought to be more practical. Storage of flood flows might be the only means by which excess water could be made available for the upper lands. No changes in existing conditions on the Kaweah River are feasible or advisable which would result in material injury to present rights. It is considered reasonable, however, that present diversions should be determined on a standard of beneficial use which, while supplying an adequate amount of water for essential crop needs, will enforce a stand- ard of practice consistent with public interest under present conditions and standards of values. Such a standard of use may be found to result in somewhat less diversion by some of those ditches having older priorities of right than may have been the practice in the past with a resulting increase in water supply available for diversion by those ditches of later priority which have been limited to shorter seasons of diversion. This would be of benefit mainly to the outer and lower por- tions of the delta as the area served by the ditches of later priority are generally those further from the stream channels. The methods of increasing the use of Kaweah River which involve changes in the present conditions of use, both legally and physically, would include transfers of existing canal rights to other areas, storage of winter flow and of excess summer flow and substitution of pumping in areas near the river channels for present canal use. It is possible to increase the production secured by the use of Kaweah River by changes in the character and location of use of parts of the present development. A transfer of all or part of the water now diverted by the Lakeside Ditch into areas not on the Kaweah Delta to areas where greater production per unit of water supply could be obtained would increase the total benefit derived from the available water supply. The substitution in the main canal area of high ground water elevation of pumped water for the present canal service with a transfer of the present canal diversions to areas of deficient canal or ground water supply would reduee the average lift of pumping, cause a draft on the ground water near the stream where replenishment takes place most readily with a corresponding lessening of the draft on those areas of least rapid recharge. A determination in definite terms of the extent of the diversion rights of existing canals both as to amount and as to the season at which diversion could be made, would enable 112 DEPARTMENT OF PUBLIC WORKS. other means of use for such portions of the discharge of Kaweah River as are not needed to supply existing rights to be undertaken. Except for the portions of the discharge now leaving the delta as outflow, such additional developments would be of the nature of changes in present conditions of use rather than the making available of new sources of supply. There is little present loss from the Kaweah Delta of the run-off during the winter months. The now at such periods is absorbed or diverted mainly for areas adjacent to the stream channel for which there is adequate replenishment available from the discharge during the main season. Storage of the winter flow would result in a lowering of the ground water near the stream channels by the general movement outward of the ground water during the winter months. This would result in having a larger capacity available for absorption of the sum- mer flow. The present use of winter flow is of some benefit to those canals which now divert during such periods. The extent of the benefit, how- ever, is considered to be less than that from use at other periods and it is not considered that any material actual injury will result to those lands near the stream channels by storage of such winter flow. Storage of winter flow might be accomplished either in surface reservoirs such as that at the Ward .site or by ground water storage in such basins as that now used by the Lindsay-Strathmore Irrigation Dis- trict. The use of ground water storage basins along the stream channel would require means of preventing the accumulation of storage from the portions of the flow to which prior rights are entitled. Means of pre- venting such refilling of ground water basin storage from water required for other rights are available. There are many surface reservoirs on streams where the portion of the use to which no storage rights attach is permitted to flow through or over the reservoir without depletion in amount. The differences physically lief ween the use of surface reser- voirs and ground water basins are ones of availability and cost rather than of the results secured. The extent to which storage of winter flow might be available if rights to its use could be secured have already been discussed. The following program represents the conclusions based on these investigations of the most feasible means of protecting the water sup- ply of the areas now developed with the minimum interference with existing conditions : 1. Complete a determination of existing rights on a basis which protects existing diversions in their essential needs but in which the standards of practice required are commensurate with present economic conditions of value of land and water. Such a determination should include a definition of the rates of diversion to which each right is entitled and a limitation of the season in whie,h such rights may be exercised. It may be secured through existing legal means or probably much more quickly and effectively by voluntary adjustment among the parties concerned if agreement by such methods can be reached. 2. Improve existing canals so as to reduce seepage losses in areas near the stream so as to deliver a larger part of the diversion to areas away from the stream in which ground water is now lowering. Increase canal capacities for those systems serving such outer areas. WATER RESOURCES OF TULARE COUNTY. 113 3. Increase pumping in areas near the river channels using pumped water as a substitute for present canal use in these areas so that the present canal use can be transferred to areas of deficient ground water supply. This will also increase ground water storage capacity for absorption of flood flow from the river channels. 4. Permit use of winter flow by storage for upper lands either in surface or ground water basins or a combination of both as may prove to be most economical. 5. Make direct transfers of present canal use from areas of less production per unit of water supply to those of a higher type of use where such transfers can be arranged. The benefits that would result from carrying out the program suggested would be the securing of sufficient additional water in the upper and outer areas to enable present development to be maintained without causing injuries to present use which could not be subject to compensation. The changes in present use in the main canal areas which would be required are matters of method of securing water rather than of amount and no material injury should result. The continuance without change of present conditions of diversion and pumping must eventually result in the reduction of the area now irrigated on some parts of the Kaweah Delta. The changes suggested would permit of the irrigation of such additional areas as could be supplied from any reduction of present use or losses such as the decrease in the amounts of water now leaving the area or the more efficient use of water now retained. For the interests of the area as a whole the maintenance of existing development is regarded as of more relative importance than the irrigation of such new areas as could be supplied by the program outlined. It is considered that it is to the interest both of the individuals concerned and of the community as a whole that land on which the cost of development has already been incurred should have its water supply protected before additional lands are brought under irrigation. Such developed lands can offer .security for higher costs in securing the water needed to supplement their existing supply than lands not developed and requiring a complete water supply. Under existing conditions all landowners have an equal right to draw upon the ground water underlying their lands for a reasonable use of such ground water. It has been shown that in several parts of the area the present ground water draft with only part of the area developed is in excess of the ground water supply. Additional pump- ing plants installed in such areas can only hasten the time when the ground water will be lowered to a point where pumping may not be profitable. The irrigation of additional land in the areas of present high ground water will intercept water now moving toward the outer areas with a resulting reduction in the supply reaching the outer areas. The changes suggested in the present conditions of use on the Kaweah Delta are all ones which require adjustment with present rights to such use. Such changes in present use are largely ones which can not be forced upon the owners of the rights to such use. There are not means of compelling an area now receiving canal service to substitute pump- ing in order that the canal service may lie carried to other areas of S — 21044 114 DEPARTMENT OF PUBLIC WORKS. deficient ground water. Storage of winter flow will to some extent affect present conditions of replenishment. The determination of what flood flow may be available for storage requires a definition of existing rights. That such adjustments can not be brought about without much delay, bitterness and cost unless approached in a spirit of fairness and community interest as a whole is indicated by the litigation which has been in progress over the pumping of the Lindsay-Strathmore Irriga- tion District for the past five years with no tangible results as yet except large costs and much ill feeling among the parties concerned. If the questions of the maintenance of the present irrigation develop- ment on the Kaweah Delta are approached with a realization of the injury that will result to the entire area from any permanent injury to any part it is thought that at least a part of the suggested changes can in time be brought about. The problems involved, however, are more largely human than technical and their solution can only be reached by a thorough realization among those directly concerned of their interest in the accomplishment of such adjustments with the minimum of injury to those affected by the changes and a maximum benefit at minimum cost to those receiving the more direct benefits. PART III. UTILIZATION OF WATER SUPPLY OF SOUTHERN PART OF TULARE COUNTY. WATER RESOURCES OF TULARE COUNTY. 117 Chapter VII. AREA DEPENDENT ON TULE RIVER FOR ITS WATER SUPPLY. The areas into which the southern part of Tulare County has been divided for the purposes of discussion are the Tule River area, the Deer Creek area, the White Creek area, and the Southwestern area. They cover all of the San Joaquin Valley in Tulare County south of the areas dependent on Kaweah River or Lewis Creek sources of water supply. The locations of the boundaries used are shown on Map 2. The actual limits of each area are in many cases indefinite and the sources of water supply for the portions near the boundaries are prob- ably the result of more or less mingling of waters from more than one source. The location of the areas irrigated is shown on Map 1, the ground water contours on Map 2, the fluctuations for 1921 on Map 3 and the general depths to ground water on Map 4. General Formations Affecting Ground Water. The water supply of the southern part of Tulare County being less than that of the Kaweah River the streams have been able to form less prominent and definite deltas. The geological formations are of more relative importance in affecting the ground water in these areas than in the northern part of the county. The eastern side of the valley is backed by the massive granitic rocks of the Sierras, which are flanked on the west by old beds of slate, intru- sions of serpentine and the resulting metamorphic schists, while these in turn are covered toward the valley by the more recent sedimentary and alluvial deposits. There is an area of older sediments generally classed as of Neocene age extending from the hills to west of Richgrove in the southern part of the county and narrowing as Tule River is approached. The local streams have cut their channels through these sediments and their recent deltas lie to the west of its outcrop. It is probable that this Neocene formation may extend out under the more recent valley alluvium and that the water secured by some of the deeper wells may be derived from its more porous strata. As its source of replenish- ment is confined to absorption from streams or precipitation on its areas of outcrop or from water contained in more recent overlying alluvium the rate of recharge and movement would be expected to be relatively slow as its outcrop is in an area of limited precipitation and run-off. As this formation contains many strata of clay the accumulation of pressure in the coarser water bearing strata is to be expected. Tb« blue clays reported in many of the deeper wells may be the capping strata of these sediments beneath which the artesian supplies are found. As this formation has had an indefinitely long period in which its more porous strata may have become filled with ground water under consid- erable pressure, the satisfactory yields of deep wells in the past or at present can not be taken as indicating the rate at which draft can be permanently maintained. These sediments were deposited at a period when this part of the San. Joaquin Valley was submerged and shows the characteristic stratification of such deposits. 118 DEPARTMENT OF PUBLIC WORKS. The recent alluvium now covering the valley floor is the result of the deposit of the material eroded by the streams from the adjacent moun- tain areas and to some extent from the older sediments of the valley edge through which the stream channels now pass. This alluvium is characteristic of such deposits in that it consists of irregular bodies or lenses of coarse and fine materials deposited by the varying discharge and meanderings of the streams. Water is usually obtainable throughout the area of such deposits. The coarser material is deposited nearer the upper portions of the deltas of the streams with the finer sands and clays carried further out into the main valley. While ground water occurs generally throughout these recent alluviums the yield obtainable from each well and the rate at which any water pumped may be replaced, depend very materially on the location of the well in relation to the source of the material forming the alluvium and to the present conditions as to location of stream channels or canals and the extent of run-off. Data available from other investigations indicates the extent of decrease in the artesian area. The reports of the State Engineer for 1878 to 1884 give data on artesian wells extending as far east as the line through Tipton, Pixley and Earlimart. Water Supply Paper 398 of the U. S. Geological Survey shows an area extending about H miles east of Tipton, one-half mile east of Pixley and one-half mile west of Earlimart as artesian. In the winter of 1920-21 the most easterly wells found to flow were several miles west of this line. The U. S. Census returns report 79 flowing wells with a total discharge of 35,513 gallons per minute used for irrigation in Tulare County in 1910. In 1920 the same returns show only 23 wells with a total discharge of 7173 gallons per minute. Some wells formerly flowing throughout the year now flow, if at all, only during the winter season. The general division of the area dependent on Tule River, Deer and White creeks from the southwestern area considered to receive its ground water from mingled sources was made on the basis of the ground water contours and type of seasonal fluctuations of the wells. In Water Supply Paper 398 a similar division is discussed based on the results of chemical analyses of the water. The location of the division between the areas in which the ground water at all depths contains very little sulphate, as given in Water Supply Paper 398, agrees generally with the division based on the data collected in these investigations. The deeper wells for an additional area to the west were found by the U. S. Geological Survey to yield water containing very little sulphate. This is considered to indicate that their source of supply is from the east side drainage areas. Such waters are at least partially artesian and may represent a mingling of several sources. The wells in the area discussed as the southwestern part of Tulare County are of this character. Extent of Tule River Area. The total area considered to be supplied from Tule River run-off has been divided into two parts. One of these is the area within which there is irrigation by canals diverting from the Tule River and the other is the area which the ground water contours indicate receives its ground water replenishment from water originating from the Tule WATER RESOURCES OF TULARE COUNTY. 119 River or the areas surface irrigated by Tule River water. As in the eases of other similar areas the actual boundaries are not definite and the actual effect of the Tule River on some parts of the area included is probably relatively small. The outer Tule area extends on the north to the center of the cone of ground water depression produced by the pumping west of Lindsay and to the Kaweah areas ; to the west to the area considered to represent the general mingled ground waters of the San Joaquin Valley trough ; to the south to the Deer Creek area and to the east to the line of contact of the granite and the valley fill or to the area considered to be dependent on Lewis Creek. TABLE 32. Areas in Acres Irrigated in Areas Dependent on Tule River for Their Water Supply. Area within area covered by canals Area irrigated in additional area dependent on Tule River for ground water supply, acres Total area, all classes, acres Area receiving canal service only, acres Area receiving canal service and supple- mental pump- ing, acres Area receiving pumping supply only, acres Total, acres Alfalfa 546 685 57 294 1,223 4,987 3,152 626 1.316 3,847 5,677 1,511 1,469 1,837 1,730 11,210 5,348 2,152 3,447 6,800 9,920 8,939 3,825 2,928 9,134 21,130 Orchards Vines _.. 14,287 5,977 Corn___ 6,375 Miscellaneous 15,934 Totals 2,805 13.928 12,224 28,957 34,746 63,703 AREAS IRRIGATED. In Table 32 the results of the data collected on the areas irrigated in 1921 are shown segregated by the source of water supply and crops. The relatively small area which depended entirely on canals for its water supply in 1921 is noticeable in this table. The crops included as miscellaneous include grain, pasture, cotton, truck and all other crops not included in the other four types shown. The orchards include both deciduous and citrus types. The segregations by ditches and by divisions of the area given later indicate the general division of these two types of orchards. The year covered by the ground water studies on the Tule River was one of less than normal run-off, the deficiency for 1920-21 on the Tule River being relatively greater than that on the Kaweah River for the same year. The actual run-off of the main Tule and of the South Fork at the gaging points of the U. S. Geological Survey from October 1, 1920, to October 1, 1921, was 90,520 acre-feet or 65 per cent of the normal. The run-off was well sustained, the discharge for June, 1921, being as large as that in some other years of much larger total annual run-off. All of the run-off in 1921 was used within the Tule River area without any outflow to Tulare Lake. The run-off while only 65 per cent of the normal in total amount was equal to 75 per cent of the average amount retained within the Tule River area. The areas irrigated in 1921 represent the present extent of develop- ment. Had there been a larger run-off in Tule River in 1921, canal irrigation would have been used to a larger extent on those lands having both sources of supply and additional areas would have been irrigated 120 DEPARTMENT OP PUBLIC WORKS. particularly under the lower ditches. The figures given, however, are considered to represent fairly closely the present extent of the area which will be irrigated in years in which the run-off does not exceed the normal supply. A total area of 63,703 acres of irrigated crop were found within the total area dependent on Tule River for its water supply. With a total mean annual run-off of 137,000 acre-feet, of which an average of 17,000 acre-feet probably leaves the area without use, one acre of crop is being irrigated for each 1.9 acre-feet of mean annual available supply. This represents a relatively heavy develop- ment in proportion to the available water supply. The area irrigated in 1921 represented 31 per cent of the gross area dependent on the Tule River for any water supplies at present available. Use by Canals. There is much less data available regarding diversions from Tule River than from Kaweah River. Measurements for the season of 1901 were made by Mr. A. E. Chandler for the Irrigation Investigation of the U. S. Department of Agriculture and are published in office of Experiment Stations Bulletin 119. Since 1901 many changes have occurred in the diversions. No complete records were obtained during these investigations. The time and funds available did not permit undertaking such measure- ments except by restricting the underground water studies and this was not considered advisable. The areas served, the general nature of the use and some measurements of diversions were obtained. There is no single definite basis on which the flow in Tule River is divided. As the result of litigation there is a general understanding of the relative rights and little controversy has arisen during recent years. Prom March 19 to April 10 of each vear the riparian owners below the east line of Sec. 15, T. 21 S., R. 26' E., receive the full flow of the river up to 400 second-feet. The upper ditches are closed as the dis- charge seldom exceeds 400 second-feet during this period. In years of more than normal run-off additional water may be received by these lower owners after April 10 if the run-off exceeds the diversions of the upper ditches. Under the larger number of the ditches diverting from the Tule River the stockholders own lands in excess of the areas for which water is available in many years. This results in variations in the areas actually irrigated in different years.- The areas actually irrigated in 1921 were obtained by direct canvass. In the South Fork of the Tule River the South Tule Independent Ditch Co. diverts below the stream gaging station. About 300 acres are served. There are some additional minor diversions and some use of water by pumping from wells in the South Fork Valley. Detailed data on such uses was not secured. The diversions on the main Tule River above the gaging station were not covered as their use of water is accounted for in the stream flow records. The irrigation by these ditches represents a small but valuable development. WATER RESOURCES OF TULARE COUNTY. 121 TABLE 33. Data on Irrigation by Ditches Diverting from Tule River— Season of 1921. Total area irrigated in 1921, acres Acreage irrigated in 1921 by crops Diversion measured June 10, 1921, sec.-ft. Area served Ditch Alfalfa Orchard Vines Corn Miscel- laneous 1901, from Bull. 119 acres North side of river — Pioneer_. _ 3,012 1,405 114 163 1,059 675 266 3,192 437 1,307 844 4,259 268 577 25 44 221 53 111 1,293 93 705 399 1,744 2,225 119 13 65 75 522 18 293 244 197 39 27 246 43 11 7 171 162 42 6 229 102 504 34 37 527 100 122 1,053 85 238 266 2,002 32 46 6 \ 35 25 '10 =50 22 19 20 1,261 Porter Slough __ ... Burton.. 100 Gilliam .. . 986 450 Hubbs and Miner South side of river — Campbell and More- 15 257 15 167 80 466 153 Poplar 296 3,000 855 Woods Central Stockton 60 20 900 395 Both sides — Lower Tule River Water Users Asso- ciation ... . ... 14,000 Totals 16,733 5,533 3.837 683 1,610 5,070 265 22,100 'Estimated. 2 MonthIy mean used. The data collected on the areas served in 1921 is assembled in Table 33. Of the total of 16,733 acres, the larger portion also received some additional supply by pumping. Such supplemental pumping supply varied from one irrigation to nearly full service. The results of measurements of the diversions on June 10. 1921, are also given in Table 33. The discharge of the main Tule River on this date was 214 second-feet and of the South Fork 16 second-feet or a total of 260 second-feet. The Stockton Ditch diverted all of the flow at that point. The sum of the diversions exceeds the record of stream flow on the date given. There were also small unmeasured diversions not included in Table 33. The figures for stream flow are the record for June 10 of the U. S. Geological Survey stations. Xo special effort was made to determine stream losses or to have the ditches maintained at a uniform rate of diversion at the time measured. Efforts were made, however, to make all measurements below the location of spillways. The results indicate either that there was such return of water to the stream by spillways or general seepage. Measurements of seepage on the ditches made in 1901. as given in Bulletin 119. show losses varying from less than 10 per eent to over 80 per cent. The average seepage loss probably exceeded 30 per cent of the diversion. On the lower ditches the present seepage losses are probably nearly as large as in 1901. It was concluded from the results of actual measurements in 1901 that there was little or no loss above the diversion of the Pioneer Canal, that there was some gain by seepage from adjoining irrigation between the Pioneer Canal and Por'terville and that below Porterville the water is gradually lost in the sandy bed. 122 DEPARTMENT OF PUBLIC WORKS. The Pioneer Ditch is the largest of the Tule River diversions serving the citrus areas. In addition to the water secured by direct diversion, there are two wells in Porterville from which water is pumped into the ditch. This ditch operates on a more definite system of delivery than most of those diverting from the Tule River and water is measured at each delivery. The records of delivery for 1920 and 1921 were exam- ined and the totals obtained. In 1921 the field canvass of the areas actually irrigated gave a total of 3012 acres as shown in Table 33. All except about 800 acres of this area received some supplemental pumped water. For 1920 the total deliveries were 3260 acre-feet and for 1921, 2500 acre-feet. The amounts delivered from the pumping plants are included in both cases. This represents an average of 1.1 and 0.8 acre-feet per acre irrigated and indicates the need of the additional .supplies secured by most of the lands from pumping. Records obtained in 1901, given in Bulletin 119, from May 19 to November 30 gave a total diversion of 10,102 acre-feet and a delivery of 2842 acre-feet or a conveyance loss of 72 per cent of the amount diverted. No continuous records of diversion were obtained in 1920 or 1921. The measurement of June 10, 1921, was made at a rate of flow which appeared to be about the average capacity of the ditch. If the same rate of flow was maintained during the times of maximum delivery a conveyance loss of about one-half the amount diverted is indicated. Tins data while incomplete indicates that a relatively large proportion of the water diverted is lost from the ditch and may become available for pumping within the area served or on lower lands. The records for 1920 from January to November give the following distribution of the total deliveries : Month, 1920 Per cent of total delivery Month, 1920 Per cent of total delivery January 6 7 1 3 30 19 July . . 15 February _ August 4 March __ September _. . _ _ . 9 April _ _ October _ _ _ _ _ 5 May .. _ . . _. November 1 June . The Porter Slough Ditch utilizes Porter Slough as a canal. The diversion is controlled by a wier and headgate at the head of Porter Slough. (Plate VIII, Fig. A.) The Burton Ditch generally received water in the winter and also after the run of the Lower Tule users. In 1921 there were four runs with a delivery of the head for one-half hour per share on each run to the 282 shares. This is equivalent to a diver- sion of about 300 acre-feet or about 2.6 acre-feet per acre for the 114 acres irrigated. The Gilliam Ditch diverts below the Burton Ditch. The Hubbs-Miner Ditch diverts through the Gilliam Ditch. The crops are diversified. On the south side of the river the Campbell and More- land Ditch, formerly called the Piano Ditch, is the upper diversion. It serves mainly citrus orchards. The upper portions of the ditch are WATER RESOURCES OF TULARE COUNTY. 123 concrete lined. The Vandalia Ditch is below and parallel to the Camp- bell and Moreland Ditch. There are 10 users under the Vandalia Ditch. The Poplar Ditch served a larger area in 1921 than any of the other Tule River diversions. It covers lower lands and has a larger propor- tion of alfalfa and mixed crops with less orchards than the ditches serving higher areas. The right of the Poplar Ditch is one of the oldest on the river. There are about 8000 acres under the ditch of which 6000 acres may be irrigated in years of favorable run-off. Sufficient observations of the flow of Poplar Ditch were made at the highway crossing south of Porterville to enable the total diversions to be estimated. Diversion began December 13, 1920, and continues through June with the exception of the time of the run for the Lower Tule users and other short periods. The total diversions were as follows : For the 3192 acres irrigated in 1921 the estimated average diverisons was 4.4 acre-feet per acre. Month Diversions in total acre- feet Month Diversions in total acre- feet December, 1920 920 1,800 2,240 1,440 2,100 May . - - - - -- 2,980 January, 1921 June 2,640 Total March __ _ 14,120 A.pril __ __ The Rhodes and Fine Ditch serves an area between the Poplar Ditch and the river. On June 10, 1921, all of the flow of the river was diverted at the head of the ditch and 41 second-feet returned to the river at the spillway. The sum of the diversions of the Woods Central and the Stockton Ditch which took the entire remaining flow on the same date was 39 second-feet. These measurements indicate little loss in con- veyance in this portion of the river. This is to be expected as hardpan occurs in portion of the stream channel. Losses by local seepage at the beginning of flow probably occur after periods of dry channel condi- tions. The Woods Central Ditch was formerly called Callison Slough. In 1921 each share received two runs. Water is used when available during the winter as well as during the summer. The Stockton Ditch is the last diversion above the Lower Tule users. In 1921 there were three runs stated to be 20 second-feet for 48 hours to each of the eight shares, or an equivalent of a total of 1920 acre-feet. For the 844 acres irrigated this is an average use of 2.3 acre-feet per acre. The diversion is shown in Plate VIII, Fig. B. The Lower Tule River Water 124 DEPARTMENT OF PUBLIC WORKS. Plate VIII, Figure A. Weir at Head of Porter Slough on Tule River. Plate VIII, Figure B. Diversion Dam of Stockton Ditch on Tulare River. WATER RESOURCES OF TULARE COUNTY. 125 Users Association comprises 37 riparian owners who by joint action secured a judgment against all of the upper ditches under which they receive the river flow up to 400 second-feet measured at the Aettle Bridge at the east line of section 15, T. 21 S., R. 26 E., for the twenty- two days from March 19 to April 10 of each year. These users have an area of 5135 acres; in many years only a portion of this area is irrigated. USE OF GROUND WATER. The rates of draft by pumping vary with the crops, soils and the extent of canal water received where this source of supply may be available. In the following tables further subdivisions of the areas have been made to correspond to differences in conditions of draft or replen- ishment of the ground water. The results for each area are given in Tables 34 and 35. The areas irrigated and the changes in ground water elevations are also shown on Maps 1 and 2. The segregation of the areas and use of water by crops in Table 34 indicates the differences in crop distribution in the different parts of the area and the extent of use of water. The amounts used per acre where pumping plants are used represent the irrigators practice under condi- tions where water is available throughout the season and where the dif- ferences in amount of use are mainly differences of cost rather than of availability of the supply. For the area not receiving any canal irrigation the average amount used for alfalfa was about three acre- feet per acre. For orchards the average use was 2.5 acre-feet per acre, being somewhat larger in the areas growing mainly citrus orchards. The extent of deciduous orchards in these areas is relatively less than on the Kaweah Delta. The use of water on vines appears to be similar in amount to that on orchards. A relatively large proportion of the vines in this area are of recent planting. The. general average amount of water pumped is only slightly less in the area served by canals than in that dependent entirely on pumps. About 50 per cent of the area receiving pumped water in the canal areas also received some canal irrigation. The pumping draft as given in Table 35 represents the amounts estimated to be drawn from the ground water by the pumps. The quantities given will exceed the net draft on the ground water by what- ever proportion of the water pumped returns to the ground water by seepage and percolation from the use of the pumped water. Iu the upper citrus areas such percolation is not to be expected. No deduc- tions in the estimated gross draft have been made for such return from irrigation ; for the conditions of soil and irrigation applying in this area a return by such losses of 10 to 20 per cent of the gross draft might be expected. The gross draft is based on the discharge and period of operation of the plants, measurements of the discharge being made where feasible. The results are thought to represent the actual draft fairly closely. The total indicated gross pumping draft for 1921 was 132,070 acre- feet. The average net available run-off of Tule River has been estimated as 120,000 acre-feet. Only a portion of this will reach the ground water as the run-off is largely diverted for .surface irrigation. It is obvious that a draft of 132,000 acre-feet can not be maintained 126 DEPARTMENT OF PUBLIC WORKS. *T o m a UJ 5 m k < £ 5 U5C5) cvi«-ieo IM CM -T3 09 § -+-> o3 09 1 X CD o co CD ONiO O r- o— i ! *-H C5S O c3 09 a OO iO CO *o uOCOt^ o t* CO ■+j ^-« 1— 1 M< ^ ^H ^ ^^CO M Ml 09 o ■* O 09 M 5 C3 co W B WNm 3 •a • to -o CO co*o CO -«*< ^^CO-CO t^. OCOOiO CM CS> (w o3 CO CM — i CO tO CO OS CO t^. Oi O CO^hCO CO O CM O ^t < o ■""" > CO to Tt< CO »-< l>" Tt* tO 00 H o>oo *0 CO ^ — < ■ iO i CM CO ' »c O 09 ■^ CM CM OS i GO-^J* i o" a) > b C3 1 • "rt 'd O CO ^ CO CO 1^- "0 -^f a> CM o c3 OW!N CO ^HOOOI" CO O SO O o C»t-i 00 OS CO o CO *H ■**<" t^" 00*" 00 t_ O r3 tHH « CD 3 H a o 1 i i i c CD -a a CD a CD -a *> ! i ! O ' ' ' a : ; : . . . 3 ^3 i « i .2 ' ' ' C 2 ; !« ^> ' ' CO * ! I ! O ca ! ^ hO ! t«-« i i O i .co 1* : 03 oa i-4 © ' 1 CD i i 3 ol 2t~ ; : O 09 "* 09 3 "o3 C a C3 -g cot-- S B 2 03CN1 3 ^ ra CD ^ a c S o bB 3 C — | o3 -; _. ; _■ ""* to ' ,» ot S " Ml -3 *e CM 03 *CD "2 *-> ^ 4m *- t- Qj u_i ~^? cy a > ° > CD CD U 03 CD is aja ^ _09 — "~"_^ S O ^ X ^ CO CO CD I* 03 M CO £ .52 os o/" 03 ~£ * » 52 . — c cp X C3 'tO CD fe CO S = X 'o "3 o u = « 5> o t- C o > x o ri c3 c3 c3 S O 09 4» 09 o o •? ti 53 B t£ 0)-OT3 JJhJi-)(-J H IS O CO H H C3 CD " J M t- (_ M •5 a WATER RESOURCES OP TULARE COUNTY. 127 TABLE 35. Areas Irrigated and Draft on Ground Water for Areas Dependent on Tule River for their Water Supply for Surface Irrigation and for Pumping. Area Gross area, acre Area irrigated by pump- ing, acre Total draft on ground water, acre-feet Draft in acre-feet per acre irrigated Draft in acre-feet per acre of gross area Lower- ing of ground water in 1921 in feet Rise in elevation of ground water, Nov. 1, 1920, to Feb. 1, 1921, feet Areas within which some lands receive canal irri- gation — Upper lands, east of west line of range 27 E Lands in range 26 E 26.200 28,800 21,800 8,365 11,167 6,623 20,893 21,097 10,394 2.5 1.9 1.6 0.80 0.75 0.50 0.35 1.20 3.30 1.6 0.3 Lands west of range 26 E.. 0.2 Totals 76,800 23,700 40,400 56,300 7,000 26,155 10.533 12,366 10,988 859 52,384 24,763 31,662 20,483 2,778 2.0 2.35 2.55 1.85 3.35 0.7 1.05 0.80 35 0.40 1.5 3.00 2.25 1.55 1.75 0.7 Areas outside of area receiving some canal irrigation but dependent on Tule River sources for their ground water supply — Area north of Tule River and northeasterly of Strathmore 3.40 Area east of west line of range 25 E. . 0.15 Area west of west line of range 25 E 1.20 Area south of Tule River in ranges 27 and 28 E._ 0.60 Totals 127,400 34,746 79,686 2.3 0.65 2.05 1.25 Total of all areas 204,200 60,901 132,070 2.2 0.65 1.85 1.05 from a supply of less than 120,000 acre-feet. The elements of uncer- tainty involved in this comparison are such that the amount of the Tule River run-off reaching the ground water can not be definitely determined and there may be some over estimation of the pumping draft. The above general comparisons indicate that the present use of the waters of Tule River approaches and probably exceeds the average net available water supply and that a continuance of present rates of use will result in a lowering of the -ground water over a long period of years. The relation of use and supply varies in the different portions of the area and such lowering will be more rapid in those portions of the area having the largest use in proportion to the supply. The data presented appears convincing that further increase in the rate of draft can not be made without a certainty of continual lowering of the ground water in some parts of the area. 128 DEPARTMENT OP PUBLIC WORKS. J r M A M J J AS M D J r ma At J J A S o At U Jo 6 We// 2-6-33 J04- J^outnu/est-^ jo; of Poplar in pumping area to ± >• 204- I Jn pumping Area n&a F>ixfey.\ /Vor/hwest of Alpaugh in oreO of ,SCc/ tiered pi/mping i . i i i_j. i i r i i" 7 , -^ 444- Wei/ T' ' ' I ^ 402 \ ft -4-oo 3S8 \ \ 1 \\ L i Near hi/Is south of \ \ /■ t^ .-- J C 394- P/anc between Tule River \ \ / "b 392 o na ' L >e ■4V2 410 .! Well 2-7- 13 ^o 6V? Between Tu/e ^4^c f? iv. r?r id D ec r Cr, of Tu/e River in arect of /itf/ei pw?7pint north of area reached by Tate r?/ ver~ Can a/ 5 sto Adjacent to area of canal i/je on /ower 71/ le ffiver r~/cj 13 sf Hydrographs of Typical Wells in Area west of Lindjaj strath more /rr tg- atton District and c/ep>e/?dent on t/ie Tute, reiver for its ^ rot* net water ^sc/pp/y 134 DEPARTMENT OF PUBLIC WORKS. Lands East of West Line of Range 25 East. The area east of the west line of range 25 east covers the portion of the Tule Delta extending- from Pixley to Tipton and eastward to the areas covered by canals. The ground water contours indicate that ground water may move into this area from Tule River sources; the extent of such movement on the outer portions of the area may be limited in amount. Present development is largely in alfalfa with a marked increase in vines in recent years. About 30 per cent of the gross area is now irrigated. The draft in 1921 was an average of 0.8 acre-feet per acre of gross area and resulted in a lowering of 2.25 feet in the water table. This rate of draft is the same as that on the upper canal served area ; the lowering was six times as great. The difference indicates the difference in conditions of ground water recharge. In general the greater amount of lowering occurred in tbe outer portions of the area. There was very little rise of the ground water during the winter of 1920-21. The average rise was 0.15 feet, being greatest on the western portions of the area. The larger winter rise in the area to the west occurs in an area which is partially artesian and may represent a recovery of pressure rather than of volume. The present rate of draft in this area represents about 25 per cent of the total available run-off of Tule River. In view of the use of this run-off both by direct canal diversion and by pumping on areas nearer its source it is hardly to be expected that this proportion of the run-off will be available in this area. It is probable that with the present rate of draft some lowering of the water table will occur in years of normal run-off. A continuation of the present rate of increase in pumping draft by the development of additional areas can only be expected to increase the rate of lowering. Lands West of West Line of Range 25 East. The area west of the west line of range 25 east includes those lands considered to receive their ground water supply from Tule River sources but which are situated relatively distant from any channel or canals supplied by Tule River. The western boundary of the area is the division between ground water derived from Tule River and those derived from general mingled sources and is necessarily indefinite. Present irrigation represents about one-fifth of the gross area, the crops being mainly alfalfa, grain, corn and pasture with very small areas of fruit or vines. The rate of draft in 1921 of 0.35 acre-feet per acre of gross area is relatively less than that in other areas. It resulted in a lowering of the ground water of 1.55 feet. There was a winter rise of 1.2 feet. As this area formerly was artesian, the winter rise is considered to be mainly a recovery of pressure rather than of volume. The ground water conditions in this area are more indefinite so that it is difficult to draw conclusions. The present conditions of use have resulted in a loss of artesian pressure so that wells which formerly flowed now flow, if at all, only during the winter months of minimum draft. The movement into this area of the 20,000 acre-feet now pumped can only be expected to occur under conditions of materially WATER RESOURCES OF TULARE COUNTY. 135 greater slope of the ground water than that now existing with the con- sequent increase in the lift required. For these two areas lying south- westerly from the area covered by Tule River canals the draft in 1921 represents 58 per cent of the total rim-off of the Tule River for that year or 43 per cent of the average available run-off. It would appear that this rate of draft in an area in which none of the run-off is applied directly to the surface is greater than the supply which can be expected to be available. The continuance of the present rate of draft can only be expected to result in a continued lowering of the ground water. The only detailed records available for the ground water fluctuations are those for 1921. There has been a continued lowering, however, in recent years, as indicated by general data collected in connection with these investigations. Data supplied by owners for fifteen wells in this area for periods varying from five to fifteen years show a lowering of the ground water of from fourteen to twenty-nine feet with an average of twenty-one feet. The larger number of these records are for wells in the western portion of the area. For five of the wells in the eastern portion of the area the lowering varied from seventeen to twenty-five feet. Lands South of Tule River Canal Area. The area south of Tule River in township 22 south, ranges 27 and 28 east, which has been included in the Tule River area, lies between the Tule River and Deer Creek. The division between the areas sup- plied from Tule River and Deer Creek is indefinite. The western por- tion of this area is probably within the zone of movement of ground water from Tule River. The eastern portion extends to the edge of the valley fill and may have only the locally tributary hill area as its source of supply. The total area included is 7000 acres of which 859 acres, practically all citrus orchard, are irrigated. The irrigated area lies in the eastern portion of the area, with practically no development in the western part of the area. It is uncertain whether there is any ground water movement from the Tule River through the depression or saddle back of Piano as there are no wells directly available on the saddle from which data on eleva- tions or materials could be obtained. Gravels occur near the surface and may extend to sufficient depths to permit some movement of ground water. The development in this vicinity is relatively heavy and the pumping has resulted in a cone of depression in the ground water as shown by the contours on Map 2. During 1921 in the eastern portion the ground water lowered as much as four feet for the full year although in the winter period a rise of six feet occurred. In the western portion there was little lowering except in the area adjacent to the pumping of the Terra Bella Irriga- tion District where the effect of the heavy draft appears to have extended into this area. Records for nine wells in the western part of this area show an average drop of six feet between 1916 and 1921. As there is prac- tically no local draft within this part of the area this lowering is due to the effect of the ground water slope in causing movement into other areas. AVhile some pumping in this area might be feasible without 136 DEPARTMENT OF PUBLIC WORKS. permanent lowering of the ground water it would appear that any such draft would he an interception of supplies now moving through this area into other areas where pumping is now practiced. SUMMARY. The preceding data and discussion of the ground water conditions of the areas dependent on Tule River for their water supply seem to warrant the following conclusions: (1) The present pumping draft closely approaches the total mean annual available run-off of Tule River. (2) While the general conditions are relatively favorable for the addition of a large part of the run-off of Tule River to the ground water, the present draft exceeds the average replenishment. (3) A consideration of the conditions on the different parts of the area shows that the greatest lowering of the ground water has occurred on those areas leas;t directly supplied and at the greatest distance from sources of percolation. The maintenance of present conditions can only be expected to result in a continued lowering of the water table in such areas. (4) Any increase in draft on such outer portions will directly increase the rate of lowering of the ground water. Any increase in draft in the portions of the area adjacent to sources of percolation will indirectly increase the lowering of the outer area by a reduction in the ground water supply available for outward movement. Many of the general features regarding the ground water supply of the Kaweah area, previously discussed, apply to the Tule area. In the case of both streams the pumping draft is resulting in lowering of the ground water in the outer parts of the areas. Much that has. been discussed in regard to possible improvements on the Kaweah River has application on the Tule River also. In the case of the Tule River present methods of use result in the canal irrigation being practiced in any area much smaller than that dependent on the Tule River for such water supply as it may receive. The same legal rights of each land owner to pump his reasonable share of the available ground water supply from under his land for its irrigation apply to both areas. It should be recognized that the exer- cise of this right by additional lands can only result in reducing the supply available for lands now developed. WATER RESOURCES OF TULARE COUNTY. 137 Chapter VIII. STORAGE SITES ON TULE RIVER. Storage on the Tule River has not been as extensively investigated in the past as it has on the other adjacent rivers. In the report by Mr. A. E. Chandler in 1901 on Duty of Water in Tule River Basin, pub- lished as a part of Bulletin 119 of the Office of Experiment Stations of the United States Department of Agriculture comments on two pro- posed sites are given. These sites are at Pleasant Valley on the main stream and just below the Indian Reservation on the South Fork. The possibility of construction of the Pleasant Valley site has been under some general discussion at various times without any definite steps look- ing toward its development being taken. Plans for the use of the site on the South Fork have been made by the South Tule Independent Ditch Company for a capacity of about 500 acre-feet, construction being contemplated as soon as the financing of the work can be arranged. The status of present water rights on Tule River, as previously discussed, indicates that there would be considerable difficulty in adjusting present diversions so as to enable any large portion of the run-off in normal years to be stored. It may well be that it would be to the advantage of at least some ditches to store a portion of the water they now receive in the earlier portion of the season for use in the late summer months but the extent of such storage is uncertain and the rearrangement of the present system of diversion of the river would be complicated. The discussion of the run-off in excess of present diver- sions shows such excess to occur in only occasional years. Its storage as a basis for a dependable annual supply would require a large capacity in proportion to the average annual use obtained from it and would only be economical in case storage sites having a very low cost per unit of capacity were available. The desirability of extensive storage on Tule River involves consid- erations both of present use of the flow and of the availability of sites. The feasibility of storage can not be settled without fairly definite data on capacity and probable cost of available sites. For this reason it was considered advisable to make surveys and prepare cost estimates for the regulation of Tule River by storage although preliminary investigations indicated that the conclusions would be unfavorable. Surveys were made of both the Pleasant Valley and the South Fork sites. On the South Fork the survey of the South Tule Independent Ditch was utilized and extended to cover a larger capacity. As the two sites are dependent on different sources of water supply they are most conveniently discussed separately. A general reconnaissance of the drainage areas of the tributaries of the main stream failed to reveal other desirable storage sites. The grades of the streams are generally steep without valley areas closed by narrow dam sites. On the Middle Fork there is a possible site below the mouth of Bear Creek ; a prelimin- ary estimate of cost and capacity indicated that the cost would be excessive and no surveys were made. 138 DEPARTMENT OF PUBLIC WORKS. PLEASANT VALLEY RESERVOIR SITE ON MAIN TULE RIVER. Map 6 shows the topography of this site. The details of the dam sites are shown on Fig. 14. The survey was carried to elevation 800 giving a total capacity of about 80,000 acre-feet. The capacity and area curves are shown in Fig. 15. Cs^fofc/om for 7%?0)Af~/ Cofac,Vy 1 7JO 750 3 6X- *7oo' "?00 "sot w /?/j-^y7ce > //) See/ fro/D JjovM esj<7 /P.jsrtS'K'* />r fret* 7s0>7r >^o<./'A f7*7 Cs*s>* of'/vrt for 72.QOO Tit: ff C e^ 7%///? £>am or? C /!&'?'!&/ of 7i//f/7 r ' f =l /-cf//e5of/9a.T7^//b>f f?/S*>r For reservoirs of over 12,000 acre-feet capacity two dams wall be required, one on the stream channel and one north of the main dam to close a depression in the rim of the reservoir. For capacities of over 60,000 acre-feet capacity a third dam would be required to close another depression in the rim. The main dam, if of masonry construction, could contain the spillway ; if of a form of construction not suitable to overpour, the spillway might be located at one of the depressions. WATER RESOURCES OP TULARE COUNTY. 139 8 250 TOO 7fO /ooo /eso /JOO /7?o eooo I | I 750 700 670 /aoeo zcpoo jcfxv jopoo jcpoo eopoo 7opoo dopoc At the main site (Plate IX, Fig. A) bed rock is not directly exposed. There are surface boulders of granitic rock both north and south of the river. Above the height of the dam on the slopes what appears to be bed rock is exposed. The depth of material over suitable bed rock on the slope is probably not excessive. There is little definite basis, how- ever, for an estimate of the depth of bedrock at the present stream channel and across the bottom of the present low land adjoining the stream. As this low land has a width of about 400 feet the depth to bedrock in this portion of the dam would materially affect the cost of construction. The probability of recommending the use of this site was not sufficient to warrant the cost of borings at this time. For a capacity of 80,000 acre-feet the length of crest of the main dam would be 1700 feet. For a capacity of 25,000 acre-feet it would be about 1400 feet. These lengths and the width of the valley bottom make some form of straight dam preferable to an arch type. Owing to the uncertainty as to depths of bedrock estimates of cost were prepared on three bases: (1) that no stripping would be required, (2) that stripping of the least amount considered probable would be required and (3) that stripping of an amount thought to be sufficient to cover any probable depth of bedrock would be required. The first assumption is obviously more favorable than can occur, the second is most favorable that can be expected and the third should include the least favorable conditions that would be expected. The depths of strip- ping given were based on examinations of surface conditions at the site and are shown in Fig. 14. 140 DEPARTMENT OF PUBLIC WORKS. Plate IX, Figure A. General View of Pleasant Valley Reservoir Site on Tule River. Plate IX, Figure B. Looking Across Main Dam Site From South End at Pleasant Valley Reservoir Site on Tule River. WATER RESOURCES OP TULARE COUNTY. 141 Cost estimates for the different assumptions regarding foundation conditions and for different capacities were made from which the curves shown in Fig. 16 have been plotted. The estimated costs were based on unit costs of $8 per cubic yard for masonry and $2 per cubic yard for stripping with items for paving, outlet gates, control of the river during construction, relocation of roads and railroad, and pur- chase of lands required. An addition of 15 per cent to the estimated cost of the above items was made to cover engineering and contin- gencies. The estimated cost of the masonry equals about 60 per cent of the estimated total cost. Cos^ /6^ sJcs-z'— 7&e^ as 1 ' £" ^fooooo /yPOOOOO far/fay /s/- ^S/f^p e>sr 7~ts/*> s^r&s-. The estimates as plotted in Fig. 16 show the cost of a masonry dam at this site to be relatively high per unit of capacity. Under the best foundation conditions to be expected the cost for the masonry dam at the largest capacity would $50 per acre-foot and might be $65 per acre-foot with foundation conditions which might be found to exist. For smaller capacities the unit costs are correspondingly greater. Estimates were also made for an earth dam across the present stream channel with spillway at one of the other two dams depending on the height of the dam. Provision for puddled cut-off trenches and for the grouting in the foundation of the main dam were made. The spillway would require concrete construction to prevent cutting back and would be more expensive and less desirable than an overpour at the main dam. 142 DEPARTMENT OP PUBLIC WORKS. An estimated cost of the earthwork of $0.60 per cubic yard was used. The material required in part at least would have to be brought from areas within the reservoir site. The estimated costs are also plotted in Fig. 16. These costs are lower than those of any masonry dam that could probably be built at this site although generally the type of con- struction would be less desirable than a masonry dam. In the following discussion of the possible use of this reservoir site the estimated cost for the earth dam has been used. In order to determine the use which might be secured from such a reservoir it was assumed that the full flow of the Tule River was available for regulation by storage so as to secure the maximum utiliza- tion of the water supply. This is equivalent to assuming that there are no existing rights which must restrict the maximum use of the w r ater supply and of approaching the study of storage on the basis of maximum usefulness. The mean annual run-off at the site since 1901 has been 120,000 acre-feet per year. Preliminary studies indicated that the annual differences in run-off would permit a regulated supply of 100,000 acre-feet per year being obtained without either excessive shortages or without excessive amounts of storage. The run-off records were compared with the monthly demands and the excess available for storage or the deficiency to be supplied from storage determined. The supply which it was attempted to maintain in each month was as follows: March, 7000 acre-feet; April, 12,000 acre-feet; Mav, 20.000 acre-feet; June, 18,000 acre-feet; July 17,000 acre-feet; August, 13,000 acre-feet ; September 13,000 acre-feet ; and October, 3000 acre-feet, The summary of the results obtained together with the estimated costs are given in Table 37. TABLE 37. Summary of Use and Cost of Storage of Different Capacities at Pleasant Valley Reservoir Site on Main Tule River. Regulated Supply for Irrigation of 100,000 Acre-feet per Year. Costs Based on Earth Dam at River with Spillway at Dam No. 2. Thousands of acre-feet unless otherwise noted g s ■ji a M w t*J *—i i— t a *— i s W H Acre-feet storage capac- ity P D n P •< o < 3 3 c CO cf CO i -i a. p c m n a. OO e •a •o ■ §| B B co £a 2 s " • S- itimated cost acre-foot of ca itv itimated cost acre-foot of n use . ^2 «*" CO co CO iS P i 8 p g *""* CO m a CO N- . CO ! Ct> 1 p ! D OO CD £' co CO timated cost acre-foot of inert in capacity timated cost acre-foot of m annual use i i ! : 1 p •a ! *< i p 1 9 /JO ov /fy> eff GROUND WATER CONTOURS <=>f SAN JOAQUIN VALLEY TULARE COUNTY ADJACENT AREAS STATE =f CALIFORNIA DEPARTMENTS PUBLIC WO RK5 DIVI5ION = f ENGINEERING ="•* IRRIGATION 7T/9 5. 77205 T20 5 T2/S. T22 5. Notes. — =— Lines indicating the bound- aries of su bcfivisions of the areas used in the ground water discussion .with number gives location of typical wells whose bydroqraphs are shown on figs 6, 7, e.s,TJ, I3A, 18 Elevations as of November I, 11Z\ Data for outer portions of Kaweah delta, Tule. River and Southern part of area., from readings of State. Department of Engineering Data farmain portion of Kaweah delta from readinqs of Lindsay- Strathmore Jrnqation Districf Readinqs from area west of Cross Greek mainly from data supplied byMox Enderlein Manager, South Kinqs River Association Dotted lines indicate location of contours to be uncertain due to Lack o-f data. Lonq dash lines represent contours for artesian strata T22 5. 77235. T24-5. based Surface water contours ondota from 550 wells- Art as ion wafer contours ar e based on data for 17 wells All elevations determined from actual leveling from US G-S datum, except for we.Hs west o-f Hanford for which depths to water were subtracted from around surface contour elevations R.23E RZ4E m$E F?.Z6E nziE PHYSICAL SCIENCES THIS BOOK IS DUE ON THE LAST DATE STAMPED BELOW BOOKS REQUESTED BY ANOTHER BORROWER ARE SUBJECT TO IMMEDIATE RECALL RECEIVED JUN 2 7 1990 PHY SCI LIBRARY AUG 9 1993 S 28 2000 If tp RECEIVED AUG 2 a 2000 PSL "S: IVED SEP^2 1J93 .'SiCALSCS. LIBRARY JAN 1 9 2000 JAN 2 7 2000 IEC1 APR 1 3 2000 LIBRARY, UNIVERSITY OF CALIFORNIA, DAVIS Book Slip-Series 458 C3Jl'#, TC&\ PHYSICAL SCIENCES LIBRARY ca A£ ~> •4- CoW obe. : <£_m o^>5 lT\ Pbdtet