Digitized by the Internet Archive in 2012 with funding from University of California, Davis Libraries http://archive.org/details/losangelescounty2455cali t Uu«ar24 57V STATE OF CALIFORNIA GOODWIN J. KNIGHT GOVERNOR PUBLICATION OF STATE WATER RESOURCES BOARD Bulletin No. 24 LOS ANGELES COUNTY LAND AND WATER USE SURVEY, 1955 MM JUNE, 1956 UNIVERSITY OF CALIFO^I,- JAN 141957 LIBRARY STATE OF CALIFORNIA GOODWIN J. KNIGHT GOVERNOR PUBLICATION OF STATE WATER RESOURCES BOARD Bulletin No. 24 LOS ANGELES COUNTY LAND AND WATER USE SURVEY, 1955 JUNE, 1956 LIBRARY UNIVERSITY OF CALIFORNIA DAVIS Vernon Industrial Area November, 1952 TABLE OF CONTENTS Pa fi e LETTER OF TRANSMITTAL, STATE WATER RESOURCES BOARD v ACKNOWLEDGMENT vi ORGANIZATION, STATE WATER RESOURCES BOARD .... ..... vii ORGANIZATION, STATE DEPARTMENT OF PUBLIC WORKS, DIVISION OF WATER RESOURCES viii CHAPTER I. INTRODUCTION 1 Authorization for Investigation A Related Investigations and Reports ... 5 Scope of Investigation and Report . 7 Area Under Investigation 10 Location and Description 10 Population ......... 13 Agriculture 15 Urban and Suburban Development 18 Water Supply . 19 Sewage and Industrial Waste Disposal . 25 CHAPTER II. LAND USE 28 Methods and Procedures 28 Results of Land Use Survey 29 San Fernando Unit 35 San Gabriel Unit 36 Pomona Unit 37 Coastal Plain Unit , . . . 37 Malibu Unit 37 TABLE OF CONTENTS (Continued) CHAPTER III. WATER REQUIREMENTS 39 Unit Values of Water Use . , , „ . „ „ . „ „ . . . . . . <> . . . . . . , 40 Present Water Requirements , . „ . . . „ „ . <, » « ■ ■ ■ „ . • <> . . . 45 Supplemental Water Requirements „ . .»» . ... » • • .... . « « e 49 CHAPTER IV. SUMMARY AND RECOMMENDATION 52 QjJTlIB.a.!iry «ocoeeooe0*oooooeooooooooa«o0ooe j£ rt© COlTirn.6riQ.cl L* lOXl «o«oo«oooooooooooeoo«oeoeo«ee >«? APPENDIX A Agreement Between the State Water Resources Board, the Los Angeles County Flood Control District, the Metropolitan Water District of Southern California, the Central Basin Municipal Water District, the West Basin Municipal Water District, the Pomona Valley Municipal Water District, and the Department of Public Works .ooooo .. 8 a O3 54 ILLUSTRATIONS Following Downtown Los Angeles, December, 1954 ooo.cooeoooo.oo* Frontispiece Vernon Industrial Area, November, 1952 . 00 <.oooo<. oco oe Frontispiece San Fernando Valley, Panorama City, February, 1948 . « . . . . . • 12 San Fernando Valley, Panorama City, January, 1952 • ... ...» • 12 Coastal Plain, Westchester, November, 1941 .<.••••••. •••• 27 Coastal Plain, Westchester, October, 1953 * • . • . . . « • • . „ . 27 San Gabriel Valley, Covina Area, March, 1941 » « • ° o . ° « <> • . ■ 38 San Gabriel Valley, Covina Area, November, 1954 <> • • » « • » • • • 38 li TABLES Table NOo Page 1 Gross Areas of Hydrologic Units, Coastal Los Angeles County . . 12 2 Populations of Principal Cities, Coastal Los Angeles County „ . 14 3 Historical Land Use, Coastal Los Angeles County ........ 17 4 Historical Seasonal Deliveries of Imported Water to Coastal Los Angeles County .................... 22 5 Deliveries of Colorado River Water to Member Agencies of Metropolitan Water District of Southern California in Coastal Los Angeles County During Seasons 1949-50 and 1954-55 . o ............. . 24 6 Historical Seasonal Discharge of Sewage and Industrial Waste to Ocean from Coastal Los Angeles County ......... 27 7 Land Use in Coastal Los Angeles County by Hydrologic Units . . 32 8 1950 Land Use in Coastal Los Angeles County by Hydrologic Units . 33 9 1955 Land Use in Coastal Los Angeles County by Areas of Cooperating Agencies ................... 34 10 Estimated Mean Seasonal Unit Values of Consumptive Use of Water on Irrigated Lands, Coastal Los Angeles County ... 43 11 Estimated Mean Seasonal Unit Values of Water Delivery and Consumptive Use of Water on Urban and Suburban Lands in Coastal Los Angeles County .............. 44 12 Estimated 1955 Mean Seasonal Requirements for Water, Coastal Los Angeles County ................... 47 13 Estimated 1950 Mean Seasonal Requirements for Water, Coastal Los Angeles County ................... 47 14 Estimated 1955 Mean Seasonal Requirements for Water Within Areas of Cooperating Agencies, Coastal Los Angeles County ......................... 49 111 Plate No, PLATES (Plates 1-8 are bound at end of bulletin) 1 Location of Coastal Los Angeles County 2 Cooperating Agencies and Hydrologic Units 3 Historical Population and Land Use in Coastal Los Angeles County 4 Historical Discharge of Sewage and Industrial Waste to Ocean from Coastal Los Angeles County 5 Present Land Use in Coastal Los Angeles County 6 Change in Land Use, 1950-55, Coastal Los Angeles County 7 Ground Water Basins and Sewered Areas with Ocean Outfall 8 Water Supplies and Water Requirements, Coastal Los Angeles County IV Goodwin J. Knight governor MR A. HILL, CHAIRMAN, REDOING /. MEIKLE, VICE CHAIRMAN, TUHLOCK *VEY O. BANKS, STATE ENGINEER SECRETARY STATE OF CALIFORNIA STATE WATER RESOURCES BOARD PUBLIC WORKS BUILDING SACRAMENTO 5, CALIFORNIA June 29, 1956 ADDRESS ALL COMMUNICATIONS TO THE SECRETARY A.FREW, King city C. A. GRIFFITH, AZUSA W. P. RICH, MARY8VILLE W. P. ROWE, SAN BERNARDINO PHIL D. SWING, SAN DIEGO Honorable Goodwin J. Knight, Governor, and Members of the Legislature of the State of California Gentlemen: We have the honor to transmit herewith Bulletin No. 2k of the State Water Resources Board, entitled "Los Angeles County Land and Water Use Survey, 1955", as authorized by Item 213. Chapter 777. Statutes of 1955. The survey of land and water use in Coastal Los Angeles County was conducted and Bulletin No. 2k was prepared by the Division of Water Resources of the Department of Public Works under the direc- tion of the State Water Resources Board, in cooperation with the Los Angeles County Flood Control District, The Metropolitan Water District of Southern California, Central Basin Municipal Water District, West Basin Municipal Water District, and Pomona Valley Municipal Water Dis- trict. Special assistance was also furnished by the City of Los Angeles, Department of Water and Power. The purpose of the investiga- tion was to determine the nature and extent of various types of land use and water requirements therefor in Coastal Los Angeles County. As a result of the investigation, it was found that, in Coastal Los Angeles County during the period from 1950 to 1955, popula- tion increased 912,000, gross water service area was expanded 36,000 acres, mean seasonal water requirements were increased 108,000 acre- feet, and supplemental water requirements remained essentially constant at about 200,000 acre-feet per season. Very truly yours, STATE WATER RESOURCES BOARD By &&u* ^^CJ ? Clair A. Chairman ACKNOWLEDGMENT Valuable assistance and data used in the investi- gation were contributed by various agencies including the following: The Los Angeles County Flood Control District, the Los Angeles County Sanitation Districts, The Metropoli- tan Water District of Southern California, the Bureau of Sanitation of the City of Los Angeles, and the Engineer's Office of the City of Vernon . The Department of Water and Power of the City of Los Angeles made a land use survey of the San Fernando Valley during the spring of 1955 and made the data available for inclusion in this bulletin. The cooperation of these agencies is gratefully acknowledged. VI ORGANIZATION STATE WATER RESOURCES BOARD Clair A. Hill, Chairman, Redding R. V. Meikle, Vice Chairman, Turlock A. Frew, King City W. Penn Rowe, San Bernardino C. A. Griffith, Azusa Phil D„ Swing, San Diego W. P. Rich, Marysville Harvey 0. Banks, State Engineer Secretary and Engineer Sam R, Leedom, Administrative Assistant vn ORGANIZATION STATE DEPARTMENT OF PUBLIC WORKS DIVISION OF WATER RESOURCES Frank B, Durkee ................. Director of Public Works Harvey 0. Banks ........... ...... State Engineer William L. Berry .......... . Assistant State Engineer This bulletin was prepared under the direction of Max Bookman, Principal Hydraulic Engineer Engineer-in-Charge of Southern California Office and Ro M„ Edmonston, Supervising Hydraulic Engineer Assistant Engineer-in-Charge of Southern California Office by Lucian J Meyers, Senior Hydraulic Engineer and Robert H. Born, Associate Hydraulic Engineer assisted by Ronald C. Hightower ............... Assistant Civil Engineer Harold P. Zablodil .................. Senior Delineator Theodore Matthews ....................... Delineator .____0- Henry Holsinger, Principal Attorney T. R, Merryweather, Administrative Officer Isabel C Nessler, Coordinator of Reports vm CHAPTER I. INTRODUCTION The phenomenal growth of population and industry in the South Coastal Area of California and particularly in Los Angeles County, which had its beginning in the first, two decades of this century, reached unprecedented heights during the 192Q ! s, moderated during the 1930* s, and equaled or ex- ceeded all previous records during the war years of the 1940 's, has,, since 1950, exceeded all previous growth records „ Population estimates and census data reveal that the growth in population of the area for the five years since 1950 has been over 900,000 or nearly twice that of the decade between 1930 and 19A-0o The Los Angeles County Regional Planning Commission reports that over 300,000 new dwelling units have been constructed in Los Angeles County from 1950 to 1955 <> A large part of the new residential area occupies lands formerly utilized for irrigated agriculture „ Rapidly expanding markets and a readily available labor pool have attracted hundreds of new industries to the area during the same periodo The foregoing cited growth of population and industry has created increasing demands for water in Los Angeles County as well as in the entire South Coastal Area 8 It is,, therefore, desirable to periodically evaluate the changes in population and land use in coastal Los Angeles County and the effect of these changes upon requirements for water therein. This information is valuable and necessary in planning present and future developments required to maintain adequate water supplies <= For a number of years prior to 1950., several of the larger ground water basins which constitute the major source of local water supplies of Los Angeles County vrere experiencing overdraft conditions, and importation facili- ties of the Los Angeles Department of Water and Power were already being utilized to very nearly their maximum capacity. Increases in water demands since 1950 have been provided for mostly by increased importation of water through the Colorado River Aqueduct. Water supplies imported through this latter facility have also reduced overdrafts in certain of the ground x^ater basins. During 195 5? nearly 400,000 acre-feet of water per season were im- ported from the Colorado River for use in the South Coastal Area, which amount represents approximately 30 per cent of total rights in and to the waters of the Colorado River claimed by agencies in the South Coastal Area» The Metropolitan Water District of Southern California has recently completed construction of facilities which will increase the capacity of the Colorado River Aqueduct from about 600 second-feet to approximately 1,000 second-feet. Because of increasing requests for imported water from its mem- ber agencies, the District has recently obtained voter authorization for, and initiated work upon, a construction program to complete the facilities of the Colorado River Aqueduct. Completion of these facilities will make possi- ble importation of approximately 1,200,000 acre-feet of water per season from the Colorado River, which amount constitutes essentially the total diversion rights in and to the waters of the Colorado River claimed by agencies in the South Coastal Area During 1951* the Division of Water Resources prepared a report on the Feather River Project, a plan to bring supplemental water to the San Joaquin Valley and southern California. The California Legislature of 1951 authorized construction of the project by the Water Project Authority, and at subsequent legislative sessions funds were appropriated for detailed studies -2~ by the Division of Water Resources leading to preparation of a report to the Legislature of 1955 presenting a program for financing and constructing the project. During the 1956 legislative session, additional funds were appro- priated for acquisition of sites and for preparation of final plans for certain features of the project in order that construction can be initiated in Fiscal Year 1958. Also, funds in the amount of $500,000 were appropriated for a study of a coastal route for the Feather River Project Aqueduct leading to the South Coastal Area, $200,000 to make investigations of routes for the aqueduct through the Tehachapi Mountains and $200,000 to make a study of alternative routes for the Feather River Project Aqueduct in San Diego County. During the 1955 legislative session, a law was passed requiring ground water users in Los Angeles, Ventura, Santa Barbara, San Bernardino, and Riverside Counties to maintain and file with the Division of Water Re- sources records of their ground water extractions in order that such informa- tion will be available for use in adjudication of rights of overlying water users to ground water supplies and to facilitate the evaluation of ground water resources in the subject areas c Also, during the 1955 legislative session, a law was passed authorizing formation of ground water replenishment districts endowed with taxing powers and having as their main purpose the preservation of ground water basins by re- plenishment thereof with imported water supplies. The previously cited rapid growth of population and industry in Los Angeles County demonstrates the need for broad scope planning for water projects to import supplemental water supplies and for organization of districts charged with the responsibility of insuring adequate water supplies. It is desirable and necessary to make periodic surveys of land use and water requirements within the area in order that such data will be available for use in planning -3- of projects and timing of their construction and also for use in guiding proper district organization and planning. The investigation herein reported upon consisted of a survey of land use and water requirements in coastal Los Angeles County for conditions of 1955. Authorization for Investigation During the spring of 195 5.« the Los Angeles County Flood Control District, the West Basin Municipal Water District, the Central Basin Munici- pal Water District, and the Pomona Valley Municipal Water District expressed interest in, and made formal request to the State Water Resources Board for, a survey of present land use and water requirements in Los Angeles County. At its regular meeting of June 3? 1955, the Water Resources Board approved a recom= mendation by the State Engineer for a one-year cooperative investigation as requested by the foregoing agencies, and directed the State Engineer to enter into a cooperative agreement with the interested agencies for the purpose of conducting the investigation,, The agreement between the State Water Resources Board, the Los Angeles County Flood Control District, The Metropolitan Water District of Southern California, the Central Basin Municipal Water District, the West Basin Municipal Water District, the Pomona Valley Municipal Water Dis- trict, and the Department of Public Works acting through the agency of the State Engineer, was entered into as of July 1, 1955 ° It provided that the work under the agreement "shall consist of (l) field surveys and office studies to determine (a) the nature and extent of present land use and water requirements, segregated by class cf use and by principal hydrologic subdivisions of coastal Los Angeles County, including San Fernando Valley, Raymond Basin Area, San Gabriel Valley Area, Pomona Area, Central Basin, West Coast Basin, and other areas comprising the Coastal Plain of Los Angeles County; (b) an estimate of -4- the present supplemental water requirement of the investigational area; (2) comparison of the results of the foregoing surveys and studies with similar data available for 1950 conditions; and (3) formulation of a report thereon." Under terms of the agreement, the investigation and report were to be completed by June 30, 1956, or as nearly thereafter as possible „ Funds to meet the cost of the investigation and report in the amount of $20,000 were provided as follows s State of California (State Water Re- sources Board), $10,000; Los Angeles County Flood Control District, $5?000; Metropolitan Water District of Southern California, $2,500; Central Basin Municipal Water District, $1,200; West Basin Municipal Water District, -$750; and Pomona Valley Municipal Water District, $550 „ A copy of the agreement between the State Water Resources Board and cooperating agencies is included in Appendix A, Related Investigations and Reports Under provisions of the authorizing agreement, data obtained in connection with the current investigation are to be compared with similar data for 1950 conditions. Pursuant to action of the California Legislature of 1947 (Chapter 1541* Statutes of 1947) and subsequent annual appropriations of funds, the State Division of Water Resources under the direction of the State Water Resources Board conducted a comprehensive investigation of the water resources of the entire State of California,, This investigation had for its purpose the preparation of The California Water Plan Results of the investigation are contained in three publications of the Water Resources Board? Bulletin No, 1, "Water Resources of California", 1951.; Bulletin No, 2, "Water Utilization and Requirements of California", June, 1955; and Bulletin No. 3 S "The California Water Plan", May, 1956 (Preliminary Edition), The -5= investigations for Bulletin No. 2 included a survey of land use and water re- quirements in the Los Angeles Metropolitan Area for conditions of 1950. Com- parisons of data compiled in the current investigation with data compiled in Bulletin No, 2 are presented hereinafter. The following reports, containing information pertinent to land and water use within coastal Los Angeles County, were also reviewed and utilized in connection with the studies hereinafter reported upon? California State Department of Public Works, Division of Water Resources. "Pacific Slope of Southern California 59 . Bulletin No. 30. (Unpublished) California State Department of Public Works., Division of Water Resources. "South Coastal Basin Investigation, Overdraft on Ground Water Basins". Bulletin No. 53 . 1947 . California State Department of Public Works, Division of Water Resources. "Report cf Referee, City of Pasadena v„ City of Alhambra, et al. Case No. Pasadena C-1323, Superior Court, Los Angeles County". July, 1943c California State Department cf Pablic Works, Division of Water Resources . "Report of Referee, California Water Service Company, a corporation, et al, v. City of Compton, et al. Case No. 506806, Superior Court, Los Angeles County". June, 1952. California State Water Resources Board. "Central Basin Investigation". Bulletin No. 8. .March, 1952. Hall, William Hammond, State Engineer. "Report of the State Engineer to the Legislature of the State of California, Session of 1880". Part IV, Appendix on Irrigation in San Bernardino and Los Angeles Counties. 1880. Hall, William Hammond, State Engineer. "Irrigation in Southern California" «, 1888. Los Angeles County Regional Planning Commission, "Master Plan of Land Use liB o 1941. Mendenhall, Walter C. "Development cf Underground Waters in the Western Coastal Plain of Southern California". United States Department of Interior, Geological Survey. Water Supply and Irrigation Paper No. 139 » 1905 o ■6- Scope of I nvestigation and Report As provided in the authorizing agreement,, the general objectives of the Los Angeles County Land and Water Use Survey included field surveys and office studies of the nature and extent of present land use and water require- ments^ estimates of present supplemental water requirements, and a comparison of the results of the surveys and studies with similar data available for 1950 conditions o In carrying out the stated objectives, full use was made of maps prepared and procedures and methods developed in connection with the prepara- tion of State Water Resources Board Bulletin No„ 2, In addition, studies were made of importation of water and the exportation of sewage and the effect of changes in these items since 1950 on supplemental water requirements of coastal Los Angeles County., Present land use in the investigational area was determined from a detailed field survey conducted in the summer of 1955« Wherever possible,, recent land use surveys in the investigational area were utilized,, Surveys completed in the spring of 1955 by the Division of Water Resources in the Raymond Basin Area and by the Los Angeles Department of Water and Power in the San Fernando Valley were adopted for use in the current investigation,, A review was made of unit values of water use derived in connection with the preparation of State Water Resources Board Bulletin No„ 2 to evaluate their applicability to 1955 conditions of development. Primary attention was given to possible changes in industrial water use. Data obtained from unit water use studies were used in conjunction with land use surveys to determine present water requirements. Safe yield of local \irater supplies was evaluated from basic data contained in the files of the Division of Water Resources,, Present supplemental water requirements were derived as the •7- difference between present water requirements and safe yield of local water supplies. Results of the Los Angeles County Land and Water Use Survey are presented in the three ensuing chapters of this report Chapter II, "Land Use "3 includes data on present land use within the investigational area, together with a discussion of methods and procedures utilized in the deriva- tion thereof,, Chapter III, "Water Requirements", contains data on unit use of water by various categories of land use together with determinations of present water requirements and present supplemental water requirements,, Chapter IV, "Summary and Recommendation" contains a brief summary of the results of the investigation and a recommendation« The following definitions of certain terms and concepts, as used in this report, are presented to facilitate understanding of the ensuing subject matter Annual - This refers to the 12-month period from January 1st of a given year through December 31st of the same years sometimes termed the "calendar year". Seasonal - This refers to any 12-month period other than the calendar year. Mean Period - A period chosen to represent conditions of water supply and climate over a long series of years For purposes of the current investi- gation, the mean precipitation period embraces the 50 seasons from 1897-93 through 1946=47;? anc * ^ ie mean runoff period, the 53 seasons from 1894-95 through 1946=47. Mean •=■ This is used in reference to arithmetical averages relating to mean periods* Average - This is used in reference to arithmetical averages relating to periods other than mean periods. Present « This is used generally in reference to land use and water supply conditions prevailing during the 1954-55 season. Ultimate - This is used in reference to conditions after an unspecified but long period of years in the future when land use and water supply develop- ment will be at a maximum and essentially stabilized. Water Utilization - This term is used in a broad sense to include all employ- ments of water by nature or man, whether consumptive or nonconsumptive, as well as irrecoverable losses of water incidental to such employment, and is synonymous with the term "water use 11 . Water R equirement - The water needed to provide for all beneficial uses and for all irrecoverable losses incidental to such uses. Present Supplemental Water Requirement - The additional water needed to provide for all present beneficial consumptive uses of water and for irrecoverable losses incidental to such use over and above the safe yield of the present water supply development. Consumptive Use of Water - This refers to water consumed by vegetative growth in transpiration and building plant tissue, and to water evaporated from adjacent soil, from water surface, and from foliage. It also refers to water similarly consumed and evaporated by urban and nonvegetative types of land use. Applied Water - The water delivered to a farmer's headgate in the case of irrigation use, or to an individual's meter in the case of urban use, or its equivalent. It does not include direct precipitation. Irrigation Efficiency - The ratio of consumptive use of applied irrigation water to the total amount of water applied, expressed as a percentage. Aquifer - A geologic formation or structure sufficiently permeable to yield water to wells or springs. Free Ground Water - A body of ground water not immediately overlain by imper- vious materials, and moving under control of the water table slope. Confined Ground Water - A body of ground water immediately overlain by material sufficiently impervious to sever free hydraulic connection with overlying water, and moving under pressure caused by the difference in head between the intake or forebay area and the discharge area of the confined water body. Safe Su rface Water Yield - The maximum dependable rate at which surface water would be available throughout a chosen critically deficient water supply period, with a given stage of surface water supply development. Safe Ground Water Yield - The maximum rate of net extraction of water from a ground water basin which, if continued over an indefinitely long period of years, would result in the maintenance of certain desirable fixed con- ditions. Commonly, safe ground water yield is determined by one or more of the following criteria? 1. Mean seasonal extraction of water from the ground water basin does not exceed mean seasonal replenishment to the basin. 2. Water levels are not so lowered as to cause harmful impairment of the quality of the ground water by intrusion of other water of undesirable quality, or by accumulation and concentration of degradants or pollutants. 3° Water levels are not so lowered as to imperil the economy of ground water users by excessive costs of pumping from the ground water basin, or by exclusion of users from a supply therefrom. Ground Water Overdraft - The rate of net extraction of water from a ground water basin in excess of safe ground water yield. Quality of Water - Those characteristics of water affecting its suitability for beneficial uses. Area Under Investigation The area under investigation, hereinafter designated "Coastal Los Angeles County", comprises that portion of Los Angeles County directly tribu- tary to the Pacific Ocean exclusive of certain portions of the San Gabriel Range within Angeles National Forest „ It includes the Los Angeles County portion of the area designated in State Water Resources Board Bulletin No. 2 as Hydrographic Unit No. 6, and also portions of Hydrographic Units Nos. 3 and 5j lying within Los Angeles County. The general location of the area is shown on Plate 1, "Location of Coastal Los Angeles County". The boundary of the investigational area is shown in detail on Plate 2, "Cooperating Agencies and Hydrologic Units" „ Location and D escription Coastal Los Angeles County comprises an area of about 1,430 square miles with an average north-south dimension of about 20 miles and a width of about 68 miles „ The area is composed of the inland San Fernando and San Gabriel Valleys separated from the Los Angeles Coastal Plain by a range of mountains crossing the area in a southeasterly direction from the Santa Monica ■10= Mountains to the Chino Hills , Elevations range from sea level to over 3,700 feet in the Santa Susana Mountains at the upper end of San Fernando Valley, San Fernando and San Gabriel Valleys are drained by the Los Angeles and San Gabriel Rivers, respectively, which cross the intermediate range at Los Angeles and Whittier Narrows, respectively, and thence cross the Coastal Plain, These principal stream systems,, together with other minor streams including Malibu, Topanga, and Ballona Creeks, enter the Pacific Ocean along a 65-mile coast line between Ventura and Orange Counties, The three main valleys or basin groups hereinbefore described are filled with absorptive alluvial or marine deposits of Recent origin underlain and generally surrounded by relatively impervious rock formations. Important soil types found in Coastal Los Angeles County include those of the Yolo,, Hanford, Tujunga, Pomona, and Chino series. Alluvial deposits in the area are faulted and folded,, resulting in hydraulic discontinuity between adjacent water-bearing formations and creating several distinctly identifiable ground water basins „ With the exception of portions of the Coastal Plain,, all ground water basins are considered to be generally unconfinedo Penetration of rainfall and percolation of stream flow to ground water in some Coastal Plain basins is restricted by the presence of a relatively impervious clay stratum or strata overlying the important pumped aquifers. Surface stream flow and precipitation enter these aquifers along the general location where they emerge at the ground surface in the forebay areas below Los Angeles and Whittier Narrows, Precipitation varies widely both seasonally and monthly, and also is subject to wide extremes of occurrence over localized areas. Precipitation generally occurs as rainfall, although rare snowfalls have been recorded through- out most of Coastal Los Angeles County, Mean seasonal precipitation varies -11= from approximately 12 inches along the coast to about 25 inches along portions of the northern boundary of the area. With the exception of the Santa Monica Mountains,, little increase in precipitation with increase in elevation occurs over the intermediate belt of hills separating the inland valleys from the Coastal Plain. The 50-year mean seasonal precipitation at Los Angeles, for the period 1897-93 through 1946-47, was 14.81 inches. Mean temperature at Los Angeles is about 63° F., ranging from a record high of 11.0°, which occurred during the current investigation, to a recorded low of 28°. Damaging winds and frost are rare and occur for short periods only. Loss of semitropical crops is usually prevented during heavy frosts by use of smudge pots or wind-making machines . For study purposes, Coastal Los Angeles County has been divided into five component units, based primarily upon topographic and geologic considera- tions. These units > designated the San Fernando Unit, San Gabriel Unit, Pomona Unit, Coastal Plain Unit, and Malibu Unit, are depicted on Plate 2, "Cooperat- ing Agencies and Hydrologic Units 88 . Gross areas of the foregoing study units are presented in Table 1. TABLE 1 GROSS AREAS OF HYDROLOGIC UNITS COASTAL LOS ANGELES COUNTY Gross area Unit t in acres San Fernando 204,000 San Gabriel 175*000 Pomona 24,000 Coastal Plain 425,000 Malibu 87,000 TOTAL 915,000 -12- San Fernando Valley Panorama City February, 1948 San Fernando Valley Panorama City January, 1952 33:331 Population The Los Angeles County Regional Planning Commission estimated the population of Coastal Los Angeles County to be 5,033,611 in July, 1955 . This figure represented an increase of about 22 per cent over the 4, 121, 712 recorded by the last decennial census in April, 1950, and an increase of nearly 47 pe r cent over the estimated population in October, 1945 . The Com- mission estimated the population of the sane area to be 5,169,641 as of April 1, 1956o The indicated net gain during the preceding nine-month period is, therefore, 136,030* Nearly 40 per cent of California's 13,000,000 plus population presently resides within Coastal Los Angeles County. Within Coastal Los Angeles County, much of the recent population increase has occurred in outlying areas relatively far removed from the con- gested downtown area. Although a major portion of the increase was the result of migration to the area from o\itside areas, a significant portion was due to the natural effect of excess of births over deaths. An average population increase of about 12 per cent has been recorded since 1950 by the 20 cities in Coastal Los Angeles County having populations in excess of 30,000 in 1955 » Presented in Table 2 are the 1940, 1950, and estimated July 1, 1955, popula- tion figures for each of the 20 cities. -13- TABLE 2 POPULATIONS OF PRINCIPAL CITIES COASTAL LOS ANGELES COUNTY 2 Population Per cent City : 1940 a s 1950 a : 1955 b increase, : 1950-55 , Alhambra 33,935 51,359 55,007 7 Arcadia 9,122 23,066 35,186 53 Beverly Hills 26,323 29,032 30,977 7 Burbank 34,337 78,577 92,782 18 Compton 16,198 47,991 64,022 33 Culver City 3,976 19,720 30,603 55 Glendale 82,532 95,702 115,057 20 Huntington Park 23, 648 29,450 30,973 5 Ingle wood 30,114 46,185 55,358 20 Lakewood c c 55,033 — Long Beach 164,271 250,767 292,107 16 Los Angeles 1,504,277 1,970,358 2,189,128 11 Pasadena 31,864 104, 577 117,057 12 Pomona 23,539 35,405 50,166 42 Redondo Beach 13,092 25,226 38,717 53 Santa Monica 53,500 71,595 77,931 9 South Gate 26,945 51,116 52,962 4 Torrance 9,950 22,241 63,467 185 West Covina 1,072 4,499 30,756 584 Whittier 16,115 23,320 32,205 3'5 a U0S0 Bureau of Census,, b Estimate by Los Angeles County Regional Planning Commission, July, 1955. c Incorporated April 16, 1954; unincorporated figures not available -14- Of particular interest are figures for the City of Lakewood, which was incorporated in April,, 1954* and had an estimated population of 55*0S3 as of July, 1955 o Virtually all of the land within the present boundaries of this city was devoted to the production of truck crops in 1950, and the popula- tion cf the area was probably less than one thousand. Also noteworthy is the extraordinary population increase of nearly 600 per cent which has occurred within the incorporated community of West Covina si*nce 1950 « In 1950, West Covina had a population of 4.9 500 \vith most of the lands within its presently incorporated limits devoted to the production of citrus fruits. By July, 1955? a majority of these lands had been subdivided, and the population was estimated to have increased to 30,756» These examples serve to illustrate the dynamic nature of current population trends in Coastal Los Angeles County, According to results of a special census completed in April, 1956, the City of Los Angeles had a population of 2, 243*901 or approximately 43 per cent of the estimated population of 5,161,863 in Coastal Los Angeles County excluding the Malibu Unit. This relationship over the years may be readily seen on Plate 3* "Historical Population and Land Use in Coastal Los Angeles County", on which a graphic comparison of the populations of the two areas since 1880 is shown. Agriculture Irrigation in Coastal Los Angeles County was first practiced by the mission padres cf San Gabrial and San Fernando missions. These missions were located where water was most abundant and where irrigation could be easily developed, and excellent harvests were reported in the early part of the 19th century. Crops were first irrigated by direct diversion from surface streams,, -15- As in other areas, the introduction of the deep well turbine pump greatly stimulated the development of irrigation in Coastal Los Angeles County » By 1926., one of the peak years prior to the depression, there were approximate- ly 209^000 acres under irrigation,, Principal crops included citrus, avocados^ walnuts, and other deciduous fruits, truck crops, and alfalfa. Up until about 1952;, Los Angeles County led all other counties in the United States in total value of farm products „ With the gradual encroachment of urban and suburban development on lands previously irrigated, however*, the total irrigated acre- age has declined until at present there are fewer acres irrigated in Coastal Los Angeles County than there were in 1904° For the year 1954? the Los Angeles County Agricultural Commissioner reported approximately 4, 10C acres of citrus orchards were converted to resi- dential subdivisions in Coastal Los Angeles County <, During the period from 1950 to 1955? valuation of citrus cropped area dropped from $31,638 ? 30G to $17^308, 000 o Large gains in nursery stock valuations have been reported in recent years by the Los Angeles County Agricultural Commissioner due to demands by subdivisions., Even with the encroachment of urban and suburban developments upon agricultural landsj irrigated farm crops still remain a substantial part, of the economy of Los Angeles County. In the year 1955, the total value of farm crops in Los Angeles County was about $260^,000,000 as compared to a similar figure of $240 ,,000 ,,000 in 1950* The increase in crop values was believed to be due mainly to a rise in price indexes rather than an increase of agricultural production, The historical growth and subsequent decline in irrigated acreage in Coastal Los Angeles County a based on results of land use surveys recorded -16« in 1880, 1888, 1904, 1926., 1932, 1942, 1950, and 1955, are presented in Table 3° Also shown are data on urban and suburban land use discussed in a later section of this report.. The historical development of irrigation is depicted graphically on Plate 3, "Historical Population and Land Use in Coastal Los Angeles County". As can be seen from Plate 3, irrigation develop- ment reached a peak in the late 1920 's. It will be noted that, of the 1,<95 square miles within Coastal Los Angeles County (excluding the Malibu Unit), 165 square miles are classified as nonhabitable . This classification of lands was made in connection with the preparation of State Water Resources Board Bulletin No. 2. It will be further noted that only about 260 square miles, or 23 per cent of the 1,130 square miles of habitable area within Coastal Los Angeles County, xvere vacant in 1955» TABLE 3 HISTORICAL LAND USE COASTAL LOS ANGELES COUNTY : Gross areas, in acres Year s Irrigated s s agriculture s Urban and : suburban t Total 1880 36,100 ■}<■ 36,100 1888 41,800 ._■/<■ 41,800 1904 94,100 13, 800 107,900 1926 219, 500 149, 800 369,300 1932 185,500 153,000 338, 500 1942 178, 500 172,100 350,600 1950 132,300 380,800 513,100 1955 87,400 456,500 543,900 * Data unavailable „ -17- Urban and Suburban Development Coastal Los Angeles County has undergone a transformation from an agricultural area to an essentially urban and suburban region, characterized by heavy industrial development „ This transformation was sharply accelerated during and following the conclusion of World War II hostilities, and has intensified to an even greater degree since 1950, Much of the increase in urban and suburban development can be attributed to the expansion of industrial and military establishments during the war and the necessity for public and private services necessary to satisfy the increased needs of the area. The desirable climatic conditions in the county have always attracted retired people „ Following the cessation of hostilities, urban and suburban construc- tion increased rapidly as more construction materials became available. The rapid groxvth of residential development in outlying areas, in- cluding adjacent Orange County, may be attributed to a number of causes, in- cluding overcrowding of the central urban area, an expanded freeway system, availability of less expensive land, and a basic desire for home ownership. The decentralization of industrial and commercial centers has created con- venient, shopping and employment opportunities in the outlying areas. Approx- imately 77 per cent of the population of Coastal Los Angeles County presently resides within incorporated cities „ Industrial development within the area has been particularly signi- ficant over the past decade* Major industries from all over the United States,, attracted by the mild climate enabling year-round employment, excellent trans- portation facilities, ready markets for manufactured goods, and a relatively abundant labor pool 5 have established branch factories, assembly plants, and distributorships in the area, During the period from 1950 to 1955, the total -13- area devoted to industry increased by 16 per cent due to new construction and expansion of the existing industries. During the same period, it is estimated that the new investment in industry in the County amounted to about $750,000,000. Already presented in Table 3 are data on urban and suburban develop- ment -within Coastal Los Angeles County based on historical land use data. The gradual encroachment of urban and suburban lands on irrigated agriculture over the years is depicted on Plate 3, "Historical Population and Land Use in Coastal Los Angeles County". Water S upply The two primary sources of water supply for Coastal Los Angeles County include water stored in underlying ground water basins, and importa- tions from the Owens and Colorado Rivers . As previously stated, surface diver- sions constituted the primary source of water supplies for early irrigation enterprises. Because of the erratic nature of this supply and due to increased demands for both irrigation and domestic water supplies, it soon became inade- quate., and wells were drilled to tap the underlying ground water aquifers. The locations of the ground water basins in Coastal Los Angeles County are shown on Plate 7? entitled "Ground Water Basins and Sewered Areas with Ocean Out fall ". Irrigation development received considerable impetus with the intro- duction of the deep well turbine pump„ It is reported that the first of such pumps was installed in a well in the Coastal Plain Unit shortly after the turn of the 20th century. Before the general development of ground water occurred, there was an excess of water rising to the surface at the natural outlets of most of the ground water basins and artesian flows existed at many points. As -19- irrigation develop;.- eased with the corresponding depletion of ground! water storage, these rising flows disappeared or were substantially reduced Local ground water overdraft conditions, or excess of net extrac- tions of ground water over replenishment , have prevailed and have developed in magnitude in certain portions of Coastal Los Angeles County since the early 19C0 C £„ Sea-water intrusion into coastal, pumped aquifers was noted as early as 1912, when perceptible quantities of saline water were pumped from we] in the Rsdondo Beach area Sea-water intrusion has historically occurred in ground water basins along almost the entire coast line of Los Angeles and Orange Counties,, Overdraft conditions are believed to prevail in the Coastal Plain Unit, where static or piezometric ground water levels have for a number of years remained below sea level over a large part of the area e A steady decline in ground water levels has been noted in wells there since as early as 1920 a It appears that the principal pumped aquifers underlying the Coastal Plain have insufficient transmitting capacity in their landward extensions to conduct water supplies to wells from forebay areas in adequate quantities to meet the water needs of 1 verlying Coastal Plain la San Fernando Valley, ground water levels have been maintained in large part through use of imported water from the Owens River System of the City of Los Angeles 6 In San Gabriel Valley, ground water conditions have been helped through use of imported water from the Colorado River and through bailment : ping from ground water by court decree (City of Pasadena v e I 3al 2d 908, 20? P 2d 17 (1949) )o Overdraft conditions were recognized in the Chino Basin in 1945, a portion of which is included the Pomona Un.ito »20» The inadequacy of local water supplies to meet the expanding municipal and irrigation needs of the area was recognized as early as 1900 ? when extensive studies were begun by the City of Los Angeles to locate sources of supplemental water. These early studies led to construction of the Los Angeles Aqueduct from the Owens River Basin and its later extension to tap the waters of the Mono Lake watersheds. Beginning in 1923, the Los Angeles area experienced a serious drought. The Owens-Mono supply was found to be inadequate to meet expected future water requirements in the City of Los Angeles. Studies were begun by the City of Los Angeles of plans for importation of water from the Colorado River. Planning and construction of the Colorado River Aqueduct was assumed by the newly formed Metropolitan Water District of Southern California in 1928 5 and the first Colorado River water reached Coastal Los Angeles County in 1941» Seasonal quantities of water imported to Coastal Los Angeles County from the two sources are presented in Table 4° It will be noted that deliveries of water from the Los Angeles Aqueduct for the past five seasons have equaled or nearly equaled the maximum capacity of the facility which is estimated to be about 320,000 acre-feet per season. =21- TABLE 4 HISTORICAL SEASONAL DELIVERIES OF IMPORTED WATER TO COASTAL LOS ANGELES COUNTY In Acre-Feet Season ending s Los Angeles j Colorado River 2 September 30 % Aaueduct § Aqueduct 5 Total 1915-16 43,700 43,700 17 68,200 __ ,__ 68, 200 18 129,300 _ — .____ 129,300 19 176,000 176,000 1919-20 202 5 300 __. — ,___ 202,300 21 187,700 -1 187,700 22 204, 600 — „____ 204, 600 23 186,300 186,300 24 149,900 _______ 149,900 1924=25 127,800 127,800 26 169,700 169,700 27 173,500 _______ 173,500 28 194,700 194,700 29 190,100 _______ 190,100 1929-30 198,100 ____ — ._ 198,100 31 215,800 > — 215,800 32 238,200 _______ 238, 200 33 228,400 228,400 34 185,600 _______ 185,600 1934-35 194,900 _______ 194,900 36 237,000 ____-_- 237,000 37 206,300 -__—- 206,300 38 209,000 _______ 209,000 39 237,300 _______ 237,300 1939-40 217,200 _______ 217,200 41 201 , 600 4,900 206,500 42 246,400 10,300 257,200 43 264,400 6,700 271,100 44 274,500 18, 500 293,000 1944=45 266,300 25,800 292,100 46 284,100 44,200 328,300 47 291,000 53,700 344,700 48 306,400 61,500 367,900 49 298, 500 61,900 360,400 1949=50 305,400 54,700 360.100 51 317,400 73,700 391,100 52 316,600 76,000 392,600 53 320,900 95,000 415,900 54 318, 600 139,200 457,300 1954=55 316,300 153,500 469,800 -22- As of January 1, 1956j 14 water agencies within Coastal Los Angeles County \tfere members of the Metropolitan Water District . These agencies had a gross area of 947 square miles. Quantities of water delivered to member agencies of the Metropolitan Water District within the investigational area during the seasons of 1949-50 and 1954-55 are presented in Table 5» The service area of the Metropolitan Water District within Coastal Los Angeles County is shown on Plate 2. •23- TABLE 5 DELIVERIES OF COLORADO RIVER WATER TO MEMBER AGENCIES OF METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA IN COASTAL LOS ANGELES COUNTY DURING SEASONS 1949-50 AND 1954-55 In Acre-Feet Season ending September 30 1949-50 1954-55 Softened Water City of Beverly Hills City of Burbank Central Basin Municipal Water District City of Compton Foothill Municipal Water District City of Glendale City of Long Beach City of Los Angeles City of Pasadena Pomona Valley Municipal Water District City of San Marino City of Santa Monica City of Torrance West Basin Municipal Water District Mis cellaneous** Subtotal Unscftened Water 400 2,100 200 1,400 1,100 3,600 300 800 13,800 16,200 5,300 29,000 17,300 17,800 1,100 10,200 11,200 2,100 8,000 2,200 30, 500 800 600 52,600 123,400 Pomona Valley Municipal Water District Los Angeles County Flood Control District*"* Mis cellaneous&* Subtotal GRAND TOTAL, SOFTENED AND UNSOFTENED 2,100 2,100 54,700 5,200 24,800 100 30,200 153,500 * Less than 50 . ** Nonmember agencies ^ water delivered on year-to-year contract basis, =24- Sewage and Industrial Waste Disposal In the early stages of urbanization of Coastal Los Angeles County^, the majority of sewage and industrial waste disposal was accomplished through use of privately-owned cesspools and septic tanks, In free ground water areas, percolation from these cesspools and septic tanks constituted an important source of replenishment to the underlying ground water basins. With increased urban and industrial areas, it has become necessary to construct extensive sewage disposal systems and treatment facilities in the interests of public health and convenience. Although more satisfactory from economic and sanitary standpoints, the installation of extensive sewage treatment and disposal works serving urbanized areas overlying free ground water basins, in effect, imposes a penalty upon the ground water basins by removing an important source of replenishment, unless the treated effluent is returned to ground water by artificial means. Coastal Los Angeles County is served by two major sewage and waste disposal agencies. The City of Los Angeles operates two systems, the first discharging its waste through the Hyperion Treatment Plant and ocean outfall located just north of the City of Manhattan Beach, and the second through a small treatment plant located on Terminal Island at the outskirts of the City of Long Beach. The second agency, the Los Angeles County Sanitation Districts, discharges waste through the Joint Disposal Plant located near Wilmington and thence through an ocean outfall located just west of San Pedro. The locations of the sewered areas with ocean outfall are shown on Plate ?» Total volume of sewage and industrial wastes discharged to the ocean through the three afore-mentioned treatment plants during 1954-55 was about 478,500 acre-feet, of which 57 per cent was discharged through the Hyperion -25- Plant* 41 per 1 through the Joint Disposal Plant; and the remaining one per cent through the Terminal Island Plant c Total discharge to the ocean during the season of 1950 was 346,500 acre- feet. Daring the five-year period from 1949~50 through 1954-55* fche total seasonal volume of sewage discharged to the ocean from areas overlying free ground water basins in Coastal Los Angeles County was increased from 71>5O0 acre-feet to Il6 5 600 acre-feet c These quantities represent 20 per cent and 24 per centp respectively, of the coincident total discharge of sewage and industrial waste to the ocean from all sewered areas in Coastal Los Angeles County P indicating a four per cent increase in the proportional quantity of sewage and industrial waste discharged to the ocean from free ground water areas Presented in Table 6 is a tabulation of quantities of sewage and industrial waste discharged to the ocean from the three treatment plants serving Coastal Los Angeles County* Comparative relationships of seasonal sewage and industrial waste discharges to the ocean from the three treatment plants are also illustrated on Plate 4* entitled "Historical Discharge of Sewage and In- trial Waste to Ocean from Coastal Los Angeles County" Not included in Table 6 g or shown on Plate k$ are minor quantities of brine waste discharged from certain oil fields which do not pass through the three major treatment plants. "•CO™ TABLE 6 HISTORICAL SEASONAL DISCHARGE OF SEWAGE AND INDUSTRIAL WASTE TO OCEAN FROM COASTAL LOS ANGELES COUNTY In Acre-Feet : City i of Los Angeles i Los Angeles County ; i Sanitation Districts : Season ending s Hyperion : Terminal Island Total September 30 : outfall : outfall j joint outfall s 1924-2$ 88, 500 2,400 • 90,900 26 92,700 2,500 95,200 27 99,700 2,500 102,200 28 102,900 2,700 2,200 107,800 29 116, 200 3,200 7,700 127,100 1929-30 126,500 3,300 10,900 140,700 31 126,700 3,100 12,900 142,700 32 128,100 2,800 14,700 145,600 33 124,700 2,900 15,300 142,900 34 112,000 2,900 16,300 131,300 1934-35 127,100 3,000 18,400 148, 500 36 130,800 3,300 20,700 154,800 37 143,900 3,400 21,200 168,500 38 147,000 3,000 26,300 176,300 39 146, 600 3,400 27, 800 177,800 1939-40 150,500 3,300 31,300 185,100 41 167,600 3,900 36,600 208,100 42 160,000 4,200 38,800 203,000 43 162,500 5,600 49,400 217, 500 44 187,400 6,500 56,700 250, 600 1944-45 178,700 6,600 57,300 242, 600 46 179,400 6,700 60,600 246,700 47 204, 600 7,000 66, 200 277,800 48 218,300 6,200 87,400 311,900 49 223,200 6,600 115,000 344,800 1949-50 213,500 6,300 126,700 346, 500 51 229,600 5,800 139,000 374,400 52 256,000 6,300 161,900 424, 200 53 258,600 5,900 168,800 433,300 54 271,300 6,500 193,700 471,500 1954-55 273,500 6,900 198,100 478, 500 -27- Coastal Plain Westchester November, 1941 Coastal Plain Westchester October, 1953 *JU~.rrrrrrrrrrrr, CHAPTER II. LAND USE The nature, location, and areal extent of present land use within Coastal Los Angeles County was determined by a detailed land use survey con- ducted during the summer of 1955- Detailed results of that survey are pre- sented in this chapter with discussion and tabulations of land use within the various hydrologic units and other appropriate subdivisions of the investiga- tional area. Methods and Procedures The survey of land use ivithin Coastal Los Angeles County was carried out through the use of generally the same methods and procedures utilized in the 1950 survey which are described in Chapter II, State Water Resources Board Bulletin No, 2« As one of the stated objectives of the current land and water use survey is to compare 1955 land and water use data with those for 1950, every attempt was made to keep methods and procedures utilized in the conduct of field work and office studies comparable with those used in the 1950 survey. Field mapping of land use in connection with the current investigation \iras carried on during the period from July through September of 1955 • The Raymond Basin area was mapped by the Division of Water Resources in a survey completed in May, 195 5* and the San Fernando Valley area was mapped by the City of Los Angeles, Department of Water and Power, in a special survey completed in April, 1955 . Data compiled from the two latter surveys were considered repre- sentative of average conditions of development prevailing in 1955, and were so utilized in this investigation. Mapping in the field was expedited by use of field maps prepared during the 1950 survey, supplemented by recent aerial photographs of the -23- entire investigational area. Where possible, a saving in time and expense was effected through noting only the changes in the nature of land vise which had occurred since the prior survey. Detailed categories or urban, suburban, and agricultural land use were mapped. In urban and suburban areas, as well as in irrigated agricultural areas, the grouping of land use categories for survey purposes was based primarily on relative water-using characteristics. Delineation of urban and agricultural lands was largely accomplished on the basis of their gross areas; that is, in general, the included areas of roads, farm lots, and other essentially nonwater- using parcels or strips of land were not segregated at the time of the survey. These items were later evaluated by application to the gross surveyed areas of appropriate percentage factors, determined from detailed surveys of representative sample plots,, Results of Land Use Survey Data obtained from the land use survey of Coastal Los Angeles County, conducted during the summer of 1955, have been compiled in tables presented hereinafter. These tables summarize the land use data for hydrologic units previously described and also for the individual agencies which cooperated in this investigation. Comparable land use data from the 1950 survey are also presented. The specific types of land use included in each of the general categories presented in the tables are set forth as follows? Water Service Areas Urban and Suburban Residential ...... Single and multiple-family houses and apartments, rural residences, rest homes, hospitals, trailer parks, and residential subdivisions under construction at time of survey „ -29- Commercial Industrial c Unclassified urban and suburban . . Included nonwater service areas Irrigated Agriculture Alfalfa ....... Pasture ....... Deciduous orchard . . Walnuts Citrus and subtropical Truck crops Hay and grain Unclassified crops Included nonwater service areas . . . Nonwate r Service Areas Nonirrigated Agriculture Native Vegetation . . . . All classes of commercial enterprises including strip commercial and downtown- type commercial areas All classes of industrial land use in- volving manufacturing, processing, packaging, and storage operations excluding oil fields and tank farms. Schools, dairies, and livestock ranches, Oil fields, tank farms, vacant lots, and public streets. Hay, seed, and pasture. Irrigated grasses and legumes other than alfalfa used for livestock forage. Includes irrigated parks. All varieties of deciduous fruits, nuts, and olives except walnuts. . Oranges, lemons, grapefruit, tangerines. and avocados. . Fresh vegetables of all varieties, flower seed, and other nursery crops. Beans, sugar beets, field com, and hops. Public highways and roads, farm access roads, and other inclusions not devotee to crop production. All varieties of dry-farmed crops in- cluding pasture. Native grasses, brush, and trees, including phreatophytes. -30- Unclassified ... Bare ground including river washes and beaches, xirater surfaces. Table 7 presents 1955 land use for the five hydrologic units compris- ing Coastal Los Angeles County. Also shown in Table 7 , for comparative pur- poses, are land use data for the entire Coastal Los Angeles County for 1950. In order to facilitate specific comparisons, 1950 land use for the same hydro- logic units is presented in Table 8. Presented in Table 9 is 1955 land use within areas of the agencies which cooperated in this investigation. Compara- ble land use data for the areas of the cooperating agencies were not compiled during the 1950 survey. Time and funds allotted for the current study were not adequate to permit re-evaluation of basic data from the 1950 survey to compile this information. -31- i~! e O 09 •»* u on L I O o &• cc e as o o W o 2 o o H 3 W ON.H 4 I •« a3 81 rH O ft. o • O O O OI O O O OS CM t^. CONDI e> ». «, «J uno ono OQ CM i-l i-l OOOQOOOOjO o ooooooooo o on en en oo im^pmW fH lf\- Ol ■ .7? C^VO VO rH CM O O °l o o o tv-tv.^: c* ct ^ CM ro o 3 O o tx o o o o o ONiH o o o o o o o o NO NO NO CM «* *\ •» oi t^J- ONO P\H rH r-t r-t o o o o o o 1 O I I O f OOOOOOOO | O oooooooo o CO en CN t-1 OO NO CM ^t j UN rH J" CO o o o o o o CM FN CNCO £"H 8 o o •c o o o o oi CM 00 [-1 ""0 * a o UNt-^ enl CM CO o o UN e-H ON o c . sF o o ON o o J- o o o o; o °I o o o o o o ° o CM J*- HJ- «-) ^ t> O O j O O I cm en i o o o o oi o o o o o o o C\ t^ en CM iHl b=J ,'5 o C C ai a> o o o o o o o o CM CM CM O O* <* 04 « OO PAH J" Cn| o o o o o o o o t-^ UN CM CO ooj- cm h o o NO o o UN en| f^ OI o ol o CO fH o UN OO oooooooo oooooooo o jd - en end- cm cm o* <* oi ot, oi e=S cn f-1 UN^- f-4 ooooooooi o olo ooooooooo olo ^- H H N W\N JCO t-^ f^l CO o O o OI o o o O o O o o CO UNCO OI en ff* Oh o» "! j eJ R, en <-) uN'-nl °1 en o ON J s o CM T3 § U 3 3 ri l« 9 Cj SO s. o' e-> - ra c5 ^32= t .J 8 « 8 o o ss «! CO O -3 e- o o o UN OS 4 I ss O 0-. T3 C lio f* CD O O O OJ o o o ©! est J^r-^-vo! « •>. •, «ii I(\0<1N0 COM H iHJ ft o o o o o 8 o o o o VO .1 & OOOOOOOO OOOOOOQQ -» o. o, <>, a, » c ONCN CNCO 9\ir\9\ «-S UNCM o o o ©1 o c S 5 oj o VO CM iH J3- •i ©* » •> -3" J^VO *-i UN V) •-( CO o] iH e\ -=N ON o o on o o 0-( o © o] o i O j O I UN I VO ) Ol o oj o VOJ ON O O Ol o o o ol o CO r-i f-ti O OOOOOOOOl O Q OOOOOOOO o © «M VO VO CM ON «N UN i-l! VO «** O O O O! O o o o oj o J3" CN e-fl 0— il ON o o o o o o o o on co ao on es >- C"J CO CO ON CO o o ON ON o CM 4% iv-i in °l E- O =33- 2 PL, o o u to e-« O o o 2 << 8 E- W) << o o w to E3 § UN UN ON h 4* a> o rH ft ■H H Bl I > ■ -i n o ~H Dj ■ -, a o s fa S a 0) o -p PL, .. 4» e ■H ■H H fa 3 s, -P c «H •w O Q +^- H r/t CO 3 fa ■1) > g -P 1 " °° 4» a c> a «- m H fa cd pa & ♦* ra ■H .j r-t O O B) *H fa 3 fa • E S ♦» 0) a! o '= ,. «6 „ XI rt fa -^ P £ CO %4 o S« O Cm C *-< ■-( ■J o d +» ■rl o H fa rH ■P c O 10 fa a, ■rt «) o o E fa •P -- 3 •i' o ►.- ■ 3 1 r-t o to 0] -J a a a <. s. 3 5 t/1 o o o o o o o o CNVO CM O t-t CO OOOOOOOOIO o oooooooolo o lf\ Jf r-< CM ON O CN C\| r-t ON o O o O o o o o O o o O o o o UN CM CM »>> •H VO •l o» 'V » • •V C r ! J- UNCNr-l o J- r4| CN r-t ON UN co o o o o o °! O Q O 1 ( 1 O O 1 o o o o o o o o O o O 1 t ! O O 1 o Q J- o UN.* CN £*-J O CM CN I t 1 UN UN | UN £ c\ • * ft *, «> ft, I 1 1 * 1 * .-( CM CM l-i t^ £**J UN CM I 9 8 J* 1 t^. CN CM a-*\ St o O O O o o o o ON VO NO O *. CO c k « M r-t > fa i? CO c D ? E cd T3 g 3 4» O is cr; o «-• t> c 03 03 O fa o fa to fa o o fa 4> x> 3 $ OS CO 4-f " 3 T3 Cd 4 s fa Bg q CO T3 O Cfl 5 O O E 5 cd ^ ^- The nature and extent of land use in Coastal Los Angeles County are illustrated graphically by color separations on Plate 5, consisting of four maps and an index sheet and entitled "Present Land Use in Coastal Los Angeles County" . Although classified as industrial-type land use, oil fields and tank farms are indicated by a special convention because of their relatively low water use as compared to other industrial developments. Nonwater service areas including nonirrigated agricultural lands and lands devoted to native vegeta- tion are not differentiated on Plate 5. The following paragraphs contain some general discussion of the re- sults of the 1955 land use survey of Coastal Los Angeles County presented in the foregoing tables and some general comparisons of the 1955 data with that obtained in the 1950 survey. During the five years from 1950 to 1955, the gross water service area increased from 508 ,,000 acres to 544,000 acres, a gain of about seven per cento Evidence of substantial urban and suburban encroachment on agricul- tural lands is shown by an increase of 82,000 acres in the gross urban and suburban area and decreases of 46,000 acres in the gross irrigated area and 22,000 acres in dry-farmed lands. The largest single loss in irrigated lands was by citrus and subtropical orchards which were reduced in areal extent by nearly 50 per cent. As would be expected, the largest increase in urban and suburban areas was in residential development of all types amounting to a 29 per cent increase during the five-year period. San Fernando Unit The San Fernando Unit experienced a net increase of about 7,000 acres in gross water service area. The balance of the 14,000 acres of expansion of urban and suburban use occurred on about 7,000 acres of formerly irrigated -35- lands principally devoted to citrus orchards. Severe inroads were also made on walnut orchards and truck farms in this unit. Most of the new urban and subur- ban development, as well as the new irrigation development, occurred in the west and northwest portions of the unit. It will be noted in Tables 7 and 8 that, for the San Fernando Unit, land area classified as "commercial" decreased from 6,200 acres to 4,500 acres from 1950 to 1955* an apparent reversal of the general increase in commercial land use in Los Angeles County. The reason for this apparent inconsistency is that the Los Angeles Department of Water and Power, in its 1950 survey of San Fernando Valley, included in its "commercial" classification schools, dairies, parks, golf courses, etc., which were classified by this Division in other categories, principally "unclassified urban and suburban" and "irrigated agri- culture". From 1950 to 1955, there was an increase in urban and suburban lands in the unit of 14, 500 acres or 23 per cent, with a corresponding decrease in irrigated lands of 7,300 acres or 23 per cento San Gabriel Unit Despite substantial residential construction in the San Gabriel Unit, principally in the El Monte-Covina area, very little net increase in the gross water service area occurred in that unit. New urban and suburban development, totaling nearly 15,000 acres, supplanted an equal area of irrigated agricultural development. Over 56 per cent of the new urban and suburban development was residential in character and nearly 73 per cent of the irrigated lands taken . of production xvere devoted to citrus orchards. From 1950 to 1955, there was an increase in urban and suburban lands in the unit of 14,900 acres or 22 per cent with a corresponding decrease in irrigated lands of 14,600 acres or 34 per cent. -36- Pomona Unit A reduction in irrigated lands was noted in the Pomona Unit, which re- duction was not completely offset by new urban and suburban development. The net loss in gross water service area of 3,400 acres represented, for the most part, lands taken out of production in anticipation of pending freeway and sub- division development. From 1950 to 1955, there was an increase in urban and suburban development in the Pomona Unit of about 2,200 acres or 40 per cent, with a corresponding decrease in irrigated lands of 5,600 acres or 51 per cent. Coastal Plain Unit The largest increase in gross water service area from 1950 to 1955 throughout Coastal Los Angeles County was found to have occurred in the Coastal Plain Unit \vhere a net increase of about 31,000 acres or 11 per cent was recordedo Substantial increases in urban and suburban lands were noted in the Lakewood, Norwalk, and Whittier areas as well as in the southwest Los Angeles area. New urban and suburban areas about 49,000 acres in extent were developedc A reduction of irrigated acreage in the amount of 18,000 acres occurred during the period„ Over half of this acreage was devoted to citrus orchards. Nearly 5,000 acres of truck crops were also taken out of production., New residential development amounted to 36,000 acres. Malibu Unit The Malibu Unit, comprising nearly 90,000 acres or approximately 10 per cent of the gross area of Coastal Los Angeles County, contained water service areas 1,900 acres in extent in 1950, or less than one per cent of the total gross water service area of Coastal Los Angeles County <, By 1955, the -37» gross water service area within the unit had grown to 3*500 acres, of which 3*000 acres were urban and suburban in character*, Most of the increase occurred along the coast in beach house and commercial development . Irrigated lands presently comprise some 500 acres „ From 1950 to 1955* there was an increase in urban and suburban lands of lc.700 acres or 130 per cent and a corresponding decrease in irrigated lands of 100 acres or 17 per cento The encroachment of urban and suburban development upon irrigated lands and vacant habitable lands is depicted graphically on Plate 3* previously referred to, The area of vacant habitable lands indicated thereon was deter- mined from land classification surveys conducted for State Water Resources Board Bulletin No e 2« The area! change in land use in Coastal Los Angeles County during the period from 1950 to 1955 is demonstrated graphically on Plate 6, "Change in Land Use, 1950-1955.S Coastal Los Angeles County",, The plate shows the expansion of water service areas since 1950 and also the extent of urbanization of lands formerly occupied by irrigated agriculture,, =33= San Gabriel Valley Covina Area March, 1941 San Gabriel Valley Covina Area November, 1954 CHAPTER III. WATER REQUIREMENTS Population growth and transformation of land use in Coastal Los Angeles County have generated great interest in their effect upon water require- mentSo As previously shown, during the period 1950 to 1955, population in the area increased over 900,000, urban and suburban areas were expanded by about 82,000 acres, and irrigated lands were decreased by an area of 46,000 acres. In the following material it will be shown that the foregoing changes resulted in an increase of 108,000 acre- feet in the water requirements of Coastal Los Angeles County. This chapter presents estimates of the total water requirement and supplemental water requirement in Coastal Los Angeles County for 1955 con- ditions and a comparison thereof with similar requirements for 1950 conditions. Estimates of water requirements in each of the component hydrologic units and service areas of cooperating agencies for 1955 conditions are also presented. Water requirements discussed in this chapter are consumptive in nature. Deter- mination of non consumptive water requirements, including those for the preser- vation and propagation of fish and wild life, flood control, repulsion of sea water from, and preservation of a suitable salt balance in, ground water basins is not within the scope of this bulletin. Present water requirements in Coastal Los Angeles County were deter- mined from land use data presented in the preceding chapter and from estimates of unit applications and unit consumptive uses of water derived as described hereinafter, with consideration given to the disposition of the unconsumed por- tion of the applied water with regard to its availability for re-use, and to losses incurred in conveyance of water to its place of use. Present supplemental water requirements in Coastal Los Angeles County were evaluated as the difference between present water requirements and the sum of the presently developed safe yield of local water supplies -39. and present imports of water from outside sources,, wherein present conditions were assumed to be those existing during 1955= Unit _ Value s of Wa ter Use In connection with the current investigation,, a review was made of unit values of water use derived in State Water Resources Board Bulletin No„ 2 studies to determine the applicability of these unit values to 1955 conditions of development . Detailed studies of water use in sample industrial areas were conducted to supplement available data in the files of the Division of Water Resources,, Results ox the foregoing studies indicated that, for the most part, mean seasonal unit values of water use derived in 1950 were still generally applicable in 1955° A complete discussion of the techniques employed in the derivation of those units is contained in Chapter 2, "Methods and Procedures" of Bulletin No, 2, and, therefore, only a general description of those proce- dures is set forth following „ In general, unit values of consumptive use of applied water for each of the irrigated crop classes were estimated, as described in Bulletin No, 2, by a modification of a method developed mainly by Harry F. Blaney and Wayne D» Criddle of the Soil Conservation Service of the United States Department of Agriculture, and outlined in their reports entitled "A Method of Estimating Water Requirements in Irrigated Areas from Climatologi cal Data", dated Decem- ber, 1947 s and "Determining Water Requirements in Irrigated Areas from Clima- tologi cal Data", dated August, 1950« The method involved correlation and ad- justment of available consumptive use data for irrigated crops in other locali- ties to correspond with experimental data and environmental conditions prevail- ing in Coastal Los Angeles County „ Unit values of applied water for the -40- various irrigated crop classes were assumed to be equal to the respective de- rived units of consumptive use of applied water divided by the respective crop irrigation efficiency. Available experimental data indicate that an average irrigation efficiency of about 70 per cent is being achieved for most crops in Coastal Los Angeles County, and this figure was utilized in the current investi- gation. Unit values of water use on urban and suburban lands were estimated on the basis of a sampling procedure in which an inventory was made of measured water deliveries to sample areas representative of each category of land use. In the case of residential and commercial areas, single blocks wholly devoted to one type of land use were chosen as sample areas. In the case of industrial areas, larger sample areas were chosen because of the greater range of unit values of water use encountered. Unit values of applied water were com- puted by dividing the amount of water delivered to a sample area by the net sampled area, excluding streets, In order to determine the reasonableness of the unit values of water use utilized in this investigation, a special study was made for certain large sections of Coastal Los Angeles County where accurate data on water deliveries were available . For the purposes of this study, data were compiled for aggre- gate service areas of eight water service companies located generally on the Coastal Plain, plus the Raymond Basin Watermaster Service Area. It was found that, for the total net water service area of 35,200 acres, the actual amount of water applied for the season 1954-55 was 140,500 acre- feet. Based upon mean seasonal units of applied water utilized in this investigation, the esti- mated total water applied to this area would have been 120 , 400 acre-feet for the season or 14 per cent less than the actual amount appliedo -41- Based upon the foregoing, it is believed that the derived theoretical unit values of applied water are quite reasonable because they are intended to reflect average conditions and the season of 1954-55 is not considered to be average,, The 1954-55 season was not only a dry season with respect to rainfall, but also one having extremely high temperatures. Rainfall at Los Angeles was only 11<>94 inches in 1954-55 > which was about 80 per cent of normal. Temper- atures were also abnormally high, reaching a maximum of 110° F„ on September 1, an all-time record high. Actual water consumption was therefore, greater than the expected long time mean values derived herein. Based on the foregoing analysis and from a detailed re-evaluation of industrial units of water use, it was concluded that units of applied water as derived for Bulletin No„ 2 are still generally applicable to 1955 conditions of development. It should be pointed out that the units of applied water, as derived, are averages not only with respect to seasonal variation but also xvith respect to areal location, and are not necessarily applicable to small localized areas wherein specific climatic or cultural conditions may produce wide variations from average con- ditions o Unit values of water use hereinafter utilized in the derivation of 1955 water requirements of Coastal Los Angeles County are presented in Tables 10 and 11. Table 10 contains estimated mean seasonal unit values of consumptive use of water on irrigated lands, and Table 11 contains estimated mean seasonal unit values of water delivery and consumptive use of water on urban and subur- ban lands. ■42- 9 s § Ed s 8 El) W D W s o u p o o ft •B Pi to a o &. .a o I w CO El E- 3 ri 3 <«> p-\ a 1 o cA cA CM 1 e- " •• i fl a o s •H -H c^s sH aS fa!*. ■»» • o CM o o CM o l-t 00 « CM J" CM CM o CM OS Q o l-l CM as o as « o • o os * o as d o ft f-1 O ON O ON © o\ so o CM l-H OS O SSI c i-« O « H d OS d St o •rt o. o fa +» JO 3 C ro n a) T3 a, fa C o 00 S fa a) <9 T3 to o •o Cm ^ fa s 3 2 M § a} +» -'J a o s o | B 5? «< Oi o > O E-" SEJ 10 O IS a bp iH a> a> o o a) a -43- TABLE 11 ESTIMATED MEAN SEASONAL UNIT VALUES OF WATER DELIVERY AND CONSUMPTIVE USE OF WATER ON URBAN AND SUBURBAN LANDS IN COASTAL LOS ANGELES COUNTY In Feet of Depth .tion s Total delivery % Consi imptive use Land use classif ica : Applied : s water s Precipi- : tation : Total Residential, single 2.6 1-3 0.9 2.2 Residential, multiple 4.5 0o3 0,6 0.9 Residential, estate 2.0 1.5 1.1 2.6 Residential, rural 1.8 0.8 0.8 1.6 Commercial, strip 3.4 0.4 0.5 0.9 Commercial, downtown 10.2 1.1 0.5 1.6 Industrial, manufacturing 9.2 1.4 0.6 2.0 Schools 0.9 0„4 0.7 1.1 Dairies 1.9 1.0 0.9 1.9 Livestock and poultry ranches 1.3 0.6 0.7 1.3 Oil fields 0.0 0.0 0.6 0.6 Vacant 0*0 0.0 0.6 0.6 Airports 0.0 0.0 0.5 0.5 Streets 0,0 0.0 0.5 0.5 -44- Present Water Requirements Quantities of total applied water and consumptive use of applied water for Coastal Los Angeles County were derived by application to the areas of land use, presented in Chapter Inappropriate unit values of water use derived in this chapter. In water service areas overlying or tributary to free ground water basins, it was assumed that all applied water in excess of consumptive use returns to underlying ground water storage and is available for re-use, except for sewage and industrial waste exported from the area. The water requirements for these areas were, therefore, estimated to be the sum of consumptive use of applied water, sei\rage export, and irrecoverable conveyance losses. In those water service areas overlying or tributary to confined ground water basins or in areas adjacent to the ocean, it was assumed that no re-use of applied water in excess of consumptive use could be effected. The water requirement for these latter areas was assumed to be equal to the total applied water plus irrecover- able conveyance losses. It has been shown that water requirements of a particular area are determined to a large degree by the interrelated topographic, geologic, and other physical conditions affecting the use and re-use of water. Depicted on Plate 7 3 entitled "Ground Water Basins and Sewered Areas with Ocean Outfall", are the major ground water basins within Coastal Los Angeles County together with the extent of overlying lands which are equipped with facilities which presently discharge their sewage and industrial waste to the ocean. A sub- stantial reduction in available local water supplies during the period 1950 to 1955 has been due to widespread extension of sewerage facilities connected to ocean outfalls into lands overlying free ground water basins; thus removing -45- an important source of replenishment to those basins. Presented in Table 12 are estimated mean seasonal water requirements in hydrologic units of Coastal Los Angeles County for conditions as of 1955. For comparative purposes^ estimated mean seasonal water requirements in hydro- logic units for 1950 conditions of development are presented in Table 13. ■46- TABLE 12 ESTIMATED 1955 MEAN SEASONAL REQUIREMENTS FOR WATER COASTAL LOS ANGELES COUNTY In Acre- •Feet Hydrologic unit ° Irrigated lands Urban and : suburban areas Total San Fernando 42,200 116,400 158,600 San Gabriel 40,300 106.800 147,100 Pomona 7,700 9,200 16,900 Coastal Plain 64,800 665,300 730,100 Malibu 800 2,200 3,000 TOTALS 155., 800 899,900 1,055,700 TABLE 13 ESTIMATED 1950 MEAN SEASONAL REQUIREMENTS FOR WATER COASTAL LOS ANGELES COUNTY In A.; ire- -Feet Hydrologic unit Irrigated lands ' Urban and : suburban areas 1 Total San Fernando 51,500 77,500 129,000 San Gabriel 59,300 71,700 131,000 Pomona 15,600 4,900 20,500 Coastal Plain 94,500 570,400 664, 900 Malibu, ^LJtQQ, 1,300 2,700 TOTALS 222,300 725,800 948,100 ■47- It is estimated that mean seasonal water requirements for conditions of 1955 in Coastal Los Angeles County were about 1,056,000 acre-feet. This is an increase of about 108,000 acre-feet or approximately 11 per cent over the seasonal i\rater requirements of 948,000 acre-feet estimated for 1950 conditions. The largest increase on a percentagewise basis occurred in the San Fernando Unit where water requirements increased about 30,000 acre-feet or about 23 per cent. The largest total gain in water requirements occurred in the Coastal Plain, where it is estimated that the total water requirements increased 65,000 acre-feet since 1950. It will be noted that the estimated water requirements in the Pomona Unit decreased about 3,600 acre-feet between the 1950 and 1955 surveys despite the extensive construction of urban and suburban developments in that area. From land use data previously presented, it will be noted that in the Pomona Unit irrigated acreage decreased from about 11,000 acres to 5,000 acres between 1950 and 1955 1 whereas urban and suburban areas increased from 5,500 acres to 7,700 acres o It was found from field investigation that a substantial area of lands in the Pomona Unit was removed from irrigated agricultural production for the purpose of being subdivided for home sites. However, at the time of this investigation, no construction work on these areas had been started. It appears that the foregoing condition Is mainly responsible for the reduction in water requirements in the Pomona Unit from 1950 to 1955 . Water requirements for conditions of 1955 were also derived for areas of each of the agencies cooperating in this investigation and are presented in Table 14, For reasons stated in Chapter II, it was not possible to compile comparable data on water requirements for the areas of the cooperating agencies for 1950 conditions . -48- TABLE 14 ESTIMATED 1955 MEAN SEASONAL REQUIREMENTS FOR WATER WITHIN AREAS OF COOPERATING AGENCIES COASTAL LOS ANGELES COUNTY In Acre-Feet : Irrigated : Urban and s Agency s lands s suburban areas % Total Los Angeles County Flood Control District 155,800 399,900 1,055,700 Metropolitan Water District of Southern California 135,200 796,400 931,600 Central Basin Municipal Water District 26, 600 139,500 216,100 West Basin Municipal Water District 17,600 90,300 103,400 Pomona Valley Municipal Water District 27,700 21,000 43,700 Supplemental Water Rei quirements Supplemental water requirements in Coastal Los Angeles County for con- ditions of 1955 were computed as the difference between the 1955 water require- ments, shown previously in this chapter, and the sum of the safe yield of local water supply sources and the 1954-55 seasonal importation from outside sources,. The safe yield of local water supply sources, derived almost entirely from ground water basins in Coastal Los Angeles County, was determined by studies of the Division of Water Resources in connection with the preparation of State Water Resources Board Bulletin No, 2 and State Division of Water Re- sources Bulletin No, 53 mentioned hereinbefore. From these studies the mean seasonal safe yield was estimated to be about 385,000 acre- feet. This estimate of safe yield is believed to be reasonably accurate and applicable to 1955 ■49- conditions of development,, It should be noted that preparation of the estimate of safe yield of local water supplies made necessary some rough approximations of the safe yields of portions of certain ground water basins around the periphery of the investigational area. This was particularly true in the Pomona Unit which includes only the western portion of the lands overlying Chino Ground Water Basin. A pro rata share of the safe yield of this latter basin was assigned to the Pomona Unit. It is believed that the foregoing is a reasonable procedure. During the season of 1954-55;, the total importation of water to Coastal Los Angeles County from outside sources was about 470,, 000 acre-feet, comprised of about 316,000 acre-feet from the Owens-Mono System of the City of Los Angeles and about 154*000 acre-feet from the Colorado River Aqueduct. It has been shown that the mean seasonal water requirement of Coastal Los Angeles County for 1955 conditions was about 1,056,000 acre-feet. The following tabulation presents a computation of the 1955 supple- mental water requirement of Coastal Los Angeles Countys Acre-feet per season Water requirement 1,056 ,,000 Water supply Safe yield of local supplies 385,000 Importation from outside sources 470 3 000 Subtotal 855,000 Supplemental water requirement 201,000 A similar computation for 1950 conditions showed that the mean seasonal supplemental water requirement of Coastal Los Angeles County at that time was about 206,000 acre-feet. It appears, therefore, that increased ■50- importations of water to the area from outside sources have just about equaled the increase of water requirements in the investigational area over the past five years, and apparent overdraft of local ground water supplies has continued essentially unchanged. Presented on Plate 8 is a graphical comparison of water supplies and water requirements in Coastal Los Angeles County for present and historical conditions insofar as records are available, and also for probable ultimate conditions as estimated in Bulletin No. 2. It will be noted that, beginning about the year 1926, water requirements in the study area exceeded local and imported water supplies by increasing amounts. Since these differences were, and are still, being supplied from ground water extractions, they are designated "apparent ground water overdraft" on Plate 8. It will be further noted that, since the water requirements shown on Plate 8 include no allowance for losses which would be incurred in importing water supplies to eliminate the apparent overdraft, the water requirements shown are slightly smaller than those tabu- lated previously in this bulletin. The ultimate water requirements of Coastal Los Angeles County shown on Plate 8 were taken from data compiled for Bulletin No. 2, and represent this Division's estimate of the probable water requirements of the area at some indefinite future date when development therein has reached its maximum level . •51- CHAPTER 17. SUMMARY AND RECOMMENDATION Summary The results of the 1955 survey cf land and water use in Coastal Los Angeles County are sujamarised as follows? lo During the period 1950 to 1955* population of Coastal Los Angeles County increased from 4$ "1-22, GOO to 5* 034*000, a growth of about 912,000 or 22 per cent, 2. The gross water service area of Coastal Los Angeles County increased from 508,000 acres in 1950 to 544*000 acres in 1955* an increase of about 36,000 acres or 7 per cento 3o The gross urban and suburban area in Coastal Los Angeles County expanded from 375*000 acres in 1950 to 457*000 acres in 1955* an increase of 82,000 acres or 22 per cent, 4 9 The gross irrigated area in Coastal Los Angeles County was reduced from 133*000 acres in 1950 to 87,000 acres in 1955* a reduction of 46,000 acres or 35 per cento 5. The mean seasonal water requirement of Coastal Los Angeles County increased from 948*000 acre-feet in 1950 to 1,056,000 acre-feet in 1955* an increase of 108,000 acre-feet or 11 per cent, 6o The supplemental water requirement in Coastal Los Angeles County has remained essentially constant, about 200,000 acre-feet per season, during the period from 1950 to 1955o It appears that importations of water from outside sources have been increased by an amount just sufficient to equal the increase in water requirements and apparent overdraft of local ground water supplies has continued essentially unchanged. Re commendat ion In view of the need for basic data relating to the current and probable continuing changes in land use and other items affecting use of water, which are prerequisite to sound water resources planning, it is recommended that a survey of land and water use similar to that reported on herein be re- peated in Coastal Los Angeles County at not less than five-year intervals. -53- APPENDIX A AGREEMENT BETWEEN THE STATE WATER RESOURCES BOARD, THE LOS ANGELES COUNTY FLOOD CONTROL DISTRICT , THE METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA. THE CENTRAL BASIN MUNICIPAL WATER DISTRICT S THE WEST BASIN MUNICIPAL WATER DISTRICT,, THE POMONA VALLEY MUNICIPAL WATER DISTRICT , AND THE DEPARTMENT OF PUBLIC WORKS -54 AGREEMENT BETWEEN THE STATE WATER .RESOURCES BOARD., THE LOS ANGELES COUNTY FLOOD CONTROL DISTRICT , THE METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA, THE CENTRAL BASIN MUNICIPAL WATER DISTRICT, THE WEST BASIN MUNICIPAL WATER DISTRICT,, THE POMONA VALLEY MUNICIPAL WATER DISTRICT, AND THE DEPARTMENT OF PUBLIC WORKS THIS AGREEMENT,, executed in quintuplicate, entered into as of July 1, 1955, by the State Water Resources Board, hereinafter referred to as the "Board", the Los Angeles County Flood Control District s The Metropolitan Water District of Southern California, the Central Basin Municipal Water District., the West Basin Municipal Water District,, the Pomona Valley Municipal Water District, all hereinafter referred to as the "Districts"; and the Department of Public Works of the State of California, acting through the agency of the State Engineer, hereinafter referred to as the "Stats Enginee W I TNES S E T H WHEREAS, by the State Water Resources Act of 1945, as amended, the Board is authorized to make investigations, studies,, surveys, hold hearings, prepare plans and estimates, and make recommendations to the Legislature in regard to water development projects, including flood control plans and projects; and WHEREAS, by said Act, the State Engineer is authorized to cooperate with any county, city, state agency,, or public district on flood control and other water problems and when requested by any thereof may enter into a coop- erative agreement to expend money in behalf of any thereof to accomplish the purposes of said act; and WHEREAS, the- Districts desire and hereby request the Board to enter into a cooperative agreement for the making of field surveys and office studies to determine the nature and extent of present land use and water requirements in principal hydroiogic subdivisions of coastal Los Angeles County, and an estimate of the present supplemental water requirements of these subdivisions; comparison of the results of the foregoing surveys and studies with similar data available for 1950 conditions; and formulation of a report thereon; -55" NOW, THEREFORE, in consideration of the premises and of the several promises to be faithfully performed by each as hereinafter set forth, the Board, the Districts, and the State Engineer do hereby mutually agree as follows: ARTICLE I - WORK TO BE PERFORMED The work to be performed under this agreement shall consist of (l) field surveys and office studies to determine (a) the nature and extent of present land use and water requirements, segregated by class of use and by principal hydrologic subdivisions of coastal Los Angeles County, including San Fernando Valley, Raymond Basin Area, San Gabriel Valley Area, Pomona Area, Central Basin, West Coast Basin, and other areas comprising the coastal plain of Los Angeles County; (b) an estimate of the present supplemental water re- quirement of the investigational area; (2) comparison of the results of the foregoing surveys and studies with similar data available for 1950 conditions; and (3) formulation of a report thereon. The Board, by this agreement, authorizes and directs the State Engineer to cooperate by conducting said investigation and formulating said report and by otherwise advising and assisting in said investigation. During the progress of said investigation, all maps, plans, informa- tion, data, and records pertaining thereto which are in possession of any party hereto, shall be made fully available to any other party hereto for the due and proper accomplishments of the objectives hereof. The work to be done under this agreement shall be diligently prose- cuted with the objective of completing the investigation and report by June 30, 1956, or as nearly thereafter as possible. -56- ARTICLE II - FUNDS The Los Angeles County Flood Control District, the Metropolitan Water District of Southern California,, the Central Basin Municipal Water Dis- trict, the West Basin Municipal Water District, and the Pomona Valley Municipal Water District, upon execution by them of this agreement shall transmit to the State Engineer the sums of Five Thousand Dollars ($5, 000), Two Thousand Five Hundred Dollars ($2,500), One Thousand Two Hundred Dollars ($1,200), Seven Hundred and Fifty Dollars ($750), and Five Hundred and Fifty Dollars ($550), respectively, for deposit subject to the approval of the Director of Finance, into the Water Resources Revolving Fund in the State Treasury, for expenditure by the State Engineer in performance of the work provided for in this agree- ment. Also, upon execution of this agreement by the Board, the Director of Finance will be requested to approve the transfer of the sum of Ten Thousand Dollars ($10,000) from funds made available to the Board by Item 213 of the Budget Act of 1955 for expenditure by the State Engineer in performance of the work provided for in this agreement and the State Controller will be requested to make such transfer.. If the Director of Finance, within thirty (30) days after receipt by the State Engineer of said sums totaling Ten Thousand Dollars ($10,000) from the Districts, shall not have approved the deposit thereof into said Water Resources Revolving Fund, together with the transfer of the sum of said Ten Thousand Dollars ($10,000) from funds made available to the Board for ex- penditure by the State Engineer in performance of the work provided for in this agreement, such sums contributed by the Districts shall be returned thereto by the State Engineer „ The Board and the State Engineer shall under no circumstances be obligated to expend for or on account of the work provided for under this "7(- agreement any amount in excess of the sum of Twenty Thousand Dollars ($20,000) as made available hereunder^, and when said sum is exhausted, the Board and the State Engineer may discontinue the work provided for in this agreement and shall not be liable or responsible for the resumption and completion thereof. Upon completion of and final payment for the work provided for in this agreement; the State Engineer shall furnish to the Board and to the Districts a statement of all expenditures made under this agreement. One-half of the total amount of all said expenditures shall be deducted from the sums advanced from funds appropriated to said Board, and one-half of the total amount cf all said expenditures shall be deducted from the sum. advanced by the Districts and any balance which may remain shall be returned to the Board,, and to the Districts,, in proportion to the sums advanced by eacho IN WITNESS WHEREOF, the parties hereto have executed this agreement to be effective as of the date hereinabove first written., Approved as to Form and Procedure HAROLD W» KENNEDY S County Counsel E By /s/ Roy W. Dowds A Attorney for Los Angeles County L Flood Control District Approved as to Form and Procedure S E /s/ James H o Howard A__ Attorney for the Metropolitan L Water District of Southern California LOS ANGELES COUNTY FLOOD CONTROL DISTRICT By /s/ John Anson Ford Chairman, Board of Supervisors Pro Tem ATTEST HAROLD Jo OSTLY, County Clerk and ex officio Clerk of the Board of Supervisors By /s/ James So Allison Deputy THE METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA By /s/ Robert Bo Diem er General Manager and Chief Engineer -53 Approved as to Form and Procedure CENTRAL BASIN MUNICIPAL WATER DISTRICT E /s/ Ralph Be Helm A By James A„ Miller L Attorney for Central Basin Municipal Water District By /s/ To Mayne Thompson., Pres, pro-tern s/Carl Fossette, Secretary Approved as to Form and Procedure iJEST BASIN MUNICIPAL WATER DISTRICT S E A L /s/ Ralph Bo Helm Attorney for West Basin Municipal Water District Approved as to Form and Procedure /s/ Morgan Wo Lowery Attorney for Pomona Valley Municipal Water District Approved as to Form and Procedure /s/ He nry Hoi singer Attorney for Division of Water Resources POMONA VALLEY MUNICIPAL WATER DISTRICT B y /s/ Carl H Lorbeer S E A L Pre So /s/ Fred C Froehde General Mgr STATE WATER RESOURCES BOARD Clair Ao Hill,, Ghairman Approved as to Form and Procedure Attorney^, Department of Public Works Approved; D-^ector of Finance State of California Department of Public Works FRANK Bo DURKEE Director of Public Works B y /s/ Ao Ho Henderson Deputy Director of Public Works Jul 27 1955 /s/ Ao Do Edmonston Ao D„ Edmonston State Engineer oSoHoYo? RoC Jo s i t Form s Budget g Value s Descript, s DEPARTMENT OF FINANCE o APPROVED i Aug 15 1955 s E A L ? JOHN Mo PEIRCE, Director ,59 _ t By /s/ Louis J Heinzer s Administrative Adviser PLATE I DIVISION OF WATER RESOURCES LOS ANGELES COUNTY LAND AND WATER USE SURVEY LOCATION OF INVESTIGATIONAL AREA 1956 AS/SANTA ~ ^./ V-_ \ %» / * / / ' f •' \ i ""»* \ «^tI| >'»» X *** /T* _.'7t ^V ' T » / V- — >- — I ANGELES NATIONAL FOREST f if r J >,a CLABEMONTf ■zr I CENTRAL BASIN MUNICIPAL WATER DISTRICT WEST BASIN MUNICIPAL WATER DISTRICT POMONA VALLEY MUNICIPAL WATER DISTRICT '909 REGULATING R£SEPvOjS ■ •••■■ METROPOLITAN WATER OISTRICT MAIN DISTRIBUTION SYSTEM CITY OF LOS ANGELES MAIN DISTRIBUTION '■" SYSTEM i^.av BOUNDARY OF INVESTIGATIONAL AREA ^ || J — ». HYOROLOGIC UNIT BOUNDARY LOS ANGELES CITY LIMITS NOTE' LOS ANGELES COUNTY FLOOD CONTROL OISTRICT BOUNDARY COINCIDES WITH LOS ANGELES COUNTY BOUNDARY FOR AREA SHOWN DIVISION OF WATER RESOURCES LOS ANGELES COUNTY LAND AND WATER USE SURVEY COOPERATING AGENCIES AND HYDROLOGIC UNITS 1955 -d POPULATION N0TF . VALUES IN GRAPHS EXCLUDE MALIBU UNIT YEARS LAND USE HISTORICAL POPULATION AND LAND USE IN COASTAL LOS ANGELES COUNTY DIVISION OF WATER RESOURCES ■ LOS ANGELES COUNTY SANITATION DISTRICTS - TOTAL DISCHARGE TO OCEAN « >- CITY OF LOS ANGELES, HYPERION CITY OF LOS ANGELES, TERMINAL ISLAND o 200,000 WATER YEAR- OCTOBER I TO SEPTEMBER 30 HISTORICAL DISCHARGE OF SEWAGE AND INDUSTRIAL WASTE TO OCEAN FROM COASTAL LOS ANGELES COUNTY DIVISION OF WATER RESOURCES LEGEND RESIDENTIAL COMMERCIAL INDUSTRIAL OIL FIELD, TANK FARM IRRIGATED AGRICULTURE MILITARY RESERVATION BOUNDARY OF INVESTIGATIONAL AREA HYDROLOGIC UNIT BOUNDARY ^ '* PRESENT LAND USE COASTAL LOS ANGELES COUNTY 1955 INDEX TO SHEETS SCALE OF MILES f II? 1 1 PRESENT LAND USE COASTAL LOS ANGELES COUNTY PRESENT LAND USE COASTAL LOS ANGELES COUNTY jHFFT? OF4 SHEETS Ci PRESENT LAND USE COASTAL LOS ANGELES COUNTY PLATE 6 NATIONAL FOREST r 1/ 5 ClAREMONt/ ' DIVISION OF WATER RESOURCES LOS ANGELES COUNTY LAND AND WATER USE SURVEY CHANGE IN LAND USE 1950-1955 \ SUSAN* \ '•.. l»' ' *. ISL/LL CANYON] PLATE 7 ••V iff ••y.. .-;- •fcy 8 ^ <0 /-J I LTTTtE I w J X S^yV ^^sspj S4N 'LIAS* I -' ANGELES NATIONAL FOREST 1 >> a * ~ ■ <« / t — \ Werdugo\ : Itj V i 717 S" ERV0 'V A Tr '"^vyggu r 'IX • e « d u g .fc> L a" ■•.^' K-J r*--v \ ■' r J *. CRESCENT* »•. <*^ s"~' -^ ' un'jx vp,, H.-C... / _.l < ~-. \TUJUNGA \''; r-J \y- UMJ-f >\ s. in iV N "S \ \ . '{WEST CMSTAL\ -T?C_ 3CEAN park Ml ^&*Sjs INGLE WO OIJ ^4 C/^/C OCEAN '•P LAJ\N \VKST COASTALl '■■AX-- ^-1. ■•' IBHSaOEWI ' , L-^_- — *j ,'rY^ \LOWH CANYON] IfftP )> ' t\ i.m a»ton,o (/ j pLa, .■ ";''S'j .7 ! iuppfff_cj7ivcwi , \yf Li f y r if gaan_ "SS 1 ""/ %\ ,..,.■.,. 1 ^ -pjg ^v ^ j ;-:x. .-^:, v • :\:-:v[ -- :;/f /ir'- L!r W ! f ;'.> •/ lA siN Arcadia) V S- ' ' ' -^y •&■:..* . I »»> ^ I ftf I waV-hVll I 'J"' .•/•!• \ * " / m M "" N0 ..-^— > jin^L. j^r 1 . :- ^3"' '$ r~£/ •••' / v V fa :# >wv, UJSJJT ?•:■• y \LOS AHCEL£S\ ^Sft | 7 MONTE BELLO ID COJJTHOL j HUNTINGTON PARK ! ICfWTffAL CIMSni. " plow pflgssoHr l/ ' N.'--i- '%._-/' ^ — 1 / r ^ ^=V LEGEND ,* * * • . GROUND WATER BASlN \CHINO\ GROUND WATER BASIN NAME SEWEREO AREAS WITH OCEAN OUTFALL *mm~~ BOUNDARY OF INVESTIGATIONAL AREA _ — HYOROLOGIC UNIT BOUNDARY LOS ANGELES CITY LIMITS Vc \ BIVIEION OF WATtK Ht»OURCI» LOS ANGELES COUNTY LAND AND WATER USE SURVEY GROUND WATER BASINS AND SEWERED AREAS WITH OCEAN OUTFALL 1950-1955 w 1.0 K .5 LEGEND WATER SUPPLIES APPARENT GROUND WATER OVERDRAFT SAFE LOCAL YIELD WATER REQUIREMENTS . • IRRIGATED LANDS ■ URBAN AND SUBURAN AREAS PROBABLE ULTIMATE WATER SUPPLIES AND WATER REQUIREMENTS COASTAL LOS ANGELES COUNTY DIVISION OF WATER RESOURCES THIS BOOK IS DUE ON THE LAST DATE STAMPED BELOW MAR i & ^ 173227 Calif. State water re- sources board. Bulletin. cv \tf TD201 C2 no.2ii IIS*' C PHYSICAL SCIENCES LIBRARY 17H227 3 1175 00457 5158