HomeMy WebLinkAbout; Tri-Agencies Water Transmission Pipeline Draft EIR; Tri-Agencies Water Transmission Pipeline Draft EIR; 1975-02-01environmental impact report CARLSBAD MUNICIPAL WATER DISTRICT CITY OF OCEANSIRE VISTA IRRIGATION DISTRICT 60A
February 1975 draft environmental impact report TRI-AGENCIES WATER TRANSMISSION PIPELINE prepared for CARLSBAD MUNICI PAL WATER Dl STRICT URS RESEARCH COMPANY 155 Bovet Road, San Mateo, California 94402 (415) 574-5000 A URS Company
STUDY ORGANIZATION This study was conducted by URS Research Company for the Carlsbad Municipal Water District, the City of Oceanside, and the Vista Irrigation District. Project direction was provided by Milton Staackmann, Vice President, URS Research Company. Robert W. Castle was Project Manager. The URS Research Company staff responsible for major contributions included 0. Leon Crain, John Kiefer, David Maiero, and Thomas Williams. Report editing, production, and direction of the URS Re- search Company Word processing Center was provided by Carol Harmon. Socioeconomic analysis was provided by URSRC economic consultant Daniel Cook; archaeological investigations were con- ducted by Stanley Berryman, Environmental Consultant.
CONTENTS Sect ion Page I INTRODUCTION ...................... 1 I I PROJECT OBJECTIVES ................... 3 I11 DESCRIPTION OF EXISTING WATER DISTRIBUTION SYSTEMS ............... 5 PROJECT DESCRIPTION ................... Physical Description .................. 7 ...................... Project Costs 11 .............. Construction Procedures 11 Operational Procedures ............... 13 V ENVIRONMENTAL SETTING .................. 17 Topography ....................... 17 Geology-Geotechnical Setting .............. 17 Soils ....................... 21 Landslides ..................... 24 Seismicity ................ ; .... 27 Mineral Resources ................. 29 .............. Unique Geologic Features 29 Atmospheric Environment ................. 30 Climatology .................... 30 AirQuality .................... 31 Hydrology/Water Resources ................ 34 Surface Waters ................... 34 Groundwater .................... 39 Imported Water .................:. 40 Wastewater Treatment and Disposal ......... 41 Biological Setting ................... 44 Flora ....................... 44 Wildlife ...................... 48 NoiseEnvironment .................... 50 ........... Archaeology and Historic Structures 50 Visual and Aesthetic Setting .............. 51 iii
CONTENTS Section Page Socioeconomic Setting .................. 51 ........... Present Socioeconomic Profile 52 Planning for the Future . Projected and Planned Growth ................. 61 ...... Comprehensive Plans and Growth Policies 73 Composite Plans and Study Maps ............ 82 .......... Future Water Supply Predictions 83 VI ENVIRONMENTAL IMPACTS OF THE PROPOSED PROJECT ...... 85 Topographic Modification ................ 85 Geotechnical Impacts .................. 85 Earthquake Shaking ................. 90 Shrink-Swell Behavior ............... 91 Erosion Potential ................. 91 Landslides ..................... 94 ................. Soil Liquefaction 94 ............. Loss of Mineral Resources 95 Air Quality Impacts ................... 98 Construction-Related Impacts ............ 98 Secondary or Indirect Impacts ........... 99 HydrologyIWater Resources ................ 106 Construction Impacts ................ 106 Long-Term (Normal Activities) Impacts ....... 106 Biological Impacts ................... 108 Noise Impact of Project ................. 110 Short-Term Impact ................. 110 Archaeology . Impacts ................... 110 Aesthetic Impacts .................... 112 ................. Long-Term Impacts 112 Socioeconomic Impacts .................. 113 Indirect Long-Term Impacts ............. 113 VII UNAVOIDABLE ADVERSE IMPACTS WHICH CANNOT BE ........ AVOIDED SHOULD THE PROJECT BE IMPLEMENTED 117
CONTENTS Section Page ................... VIII MITIGATINGMEASURES 121 ..................... Erosioncontrol 121 .......................... Dust 122 .......................... Noise 122 .................. Biology Revegetation 122 ....................... Archaeology 123 ..................... Socioeconomics 124 .......... IX ALTERNATIVES TO THE PROPOSED PROJECT 125 ....................... No Project 125 ............. Construction of Three Pipelines 126 ................ Alternate Pipeline Routes 126 RELATIONSHIP BETWEEN LOCAL SHORT-TERM USES OF MAN'S ENVIRONMENT AND THE MAINTENANCE AND .......... ENHANCEMENT OF LONG-TERM PRODUCTIVITY 129 ........... IRREVERSIBLE ENVIRONMENTAL IMPACTS 131 THE GROWTH-INDUCING IMPACT OF .................... PROPOSED PROJECT 133 Water Service as Indirect Facilitator ............ of Population and Economic Growth 133 Land-Use Planning and Policy. and the Use of Water Services as a Tool to Guide .......... or Limit Population and Urban Growth 133 .................. GENERAL BIBLIOGRAPHY 139 APPENDICES A Noise Criteria B Report on the Archaeological Resources of the Tri-Agencies Pipeline
TABLES Number Page 1 Peak Day Water Demands and Peak Day Factor, ............... Tri-Agencies Service Area. 6 .................. 2 Soil Characteristics 25 3 Air Quality Data Summary - .................... ElCajon--1973 32 ............. Ambient Air Quality Standards. 33 ....... Hydrographic Units of the San Diego Basin. 36 Estimated Mean Seasonal Natural Runoff for ..... Hydrographic Units Within the San Diego Region 38 Comparison of the Water Quality of Water Derived from the Colorado River and ................ the Statewaterproject. 42 Flora Typical to Coastal ScrubIChaparral ............... andGrassland Communities. 46 ............ Wildlife Typical to Project Area 49 1973 Statistical Profile of the Socioeconomic Character of the Tri-Agencies Service Area and ........ Community Statistical Subregional Areas. 53 Summary of 1971 Land Use by Major Category Cities ........... of Carlsbad, Oceanside, and Vista. 58 Basic Projected Planning Statics - 1975-1995 Tri-Agency Service Area, Combined Community ........................ Areas.. 66 Basic Projected Planning Statistics - 1975-1995 Subregional Community Statistical AreasITri- ............... Agency Water Services Area 68 Projected Population Growth: 1975-1995 - Subregional Community Statistical AreasfTri- ...... Agency Water Services Area by Census Tracts. 70
TABLES Page 15 Geologic Problems and Severity Ratings ......... 87 16 Construction Air Pollution Potential .......... 100 17 Range of Particulate Valued Which May Occur for Pipeline Projects. ............ 101 18 Range of Gaseous Concentrations Which May Occur for Pipeline Projects. ............ 102 19 Probability of Certain Limiting Standards Being Exceeded During Periods of Construction. ..... 103 20 Date Federal Air Quality Standards Will Be Met Given Alternative Population and Technological Assumptions. ............... 107
FIGURES Number Page Location Map. Tri-Agency Pipeline ............ 8 Schematic Drawing of the Proposed Tri-Agency Pipeline ................... 14 General Geology ..................... 18 Faults ......................... 22 ....... Soils Map . Vicinity of Tri-Agency Pipeline 23 Areas of Relative Amounts of Landslides ......... 26 Earthquake Epicenters in Southern California ...... 28 The Water Resource Elements of the San Diego Region .................... 35 Hydrographic Units of the San Diego Basin ........ 37 Distribution of Plant Communities ............ 45 Project Population. 1973-1995: San Diego County Region. Tri-Agency Service Area. and ......... Community Subregional Statistical Areas 65 .............. Summary of Geologic Problems 86 Ranges of Maximum Accelerations in Rock ......... 89 ................. Swell-Shrink Potential 92 Susceptibility to Erosion ................ 93 Limitations for Conversion From BrushtoGrass ..................... 96 Potential Sources of Construction Material ....... 97 ............. Air Pollution Carrying Capacity 105 viii
Section I INTRODUCTION The San Diego County Water Authority (SDCWA) and three member agencies, the Carlsbad Municipal Water District, the City of Oceanside, and the Vista Irrigation District have retained URS Research Company to prepare an Environmental Impact Report with the objective of assessing - the beneficial and adverse environmental implications of the construction and operation of the proposed Tri-Agency water distribution system. Since 1950 the population of San Diego County has tripled. In the period 1960 to 1970 population growth in San Diego County accounted for 11 percent of the California total. This expansion has resulted in tremendous demands for water, the majority of which (90%) must be import- ed due to lack of local resources. Historically this imported water has come from the Colorado River through aqueducts operated by the Metropolitan Water District of South California (MWD). Recent legisla- tion and completion of the State Water Project will soon change the source of this imported water from the Colorado River to higher quality Northern California (Feather River) water. The MWD, SDCWA, and some of the SDCWA member agencies are currently adapting their treatment and distribution systems to accommodate this change. The existing water supply system in the Vista-Carlsbad-Oceanside area is currently near the point where its capacity is insufficient to meet peak demands. Additionally, the present system is inadequate to serve the outlying areas currently undergoing or planned for development. The proposed Tri-Agency Pipeline will solve the immediate water supply problems within each system, and will meet the water requirements of the planned development of each service area.
Section I1 PROJECT OBJECTIVES The most immediate objective of the proposed project is to relieve the existing problem of maintaining adequate flow in the existing sys- tems of Carlsbad, Oceanside, and Vista during periods of peak flow de- mand. The relatively high hydraulic gradient proposed will allow the existing systems to be back-fed under pressure. Backfeeding will supplement flow at the extreme ends of these systems where head losses are at a maximum, thereby extending their useful lives and the impend- ing need for major modifications. The pipeline will be routed into several other existing storage facilities, including Squires Reservoir, increasing the systems flexi- bility to meet peak demands in the future. Major connections will be provided for the future installation of new supply to the Vista I.D. No other provisions for the accommodation of major connections are pro- posed. The bulk of the planned service area is preliminarily zoned for residental density use and the pipline sized accordingly for the pro- jected population. The existing and future water supply requirements of three respective agencies have been combined into a single jointly funded and operated system with the objective of significantly reducing the overall project costs. While thereby reducing overall costs passed to the consumer (from the costs of three separate pipelines), the unification of the agencies' requirements into a single project will similarly reduce a num- ber of possible environmental impacts. Timing of the project is critical if uninterrupted service is to be maintained in the next several years. Approximately one year will be re- quired from the start of construction to actual water transmission. As
peak demands may not be accommodated presently, service interruptions are a potential threat. The San Diego County Water Agencies have historically been successful in avoiding water shortages through timed construction, although by narrow margins on several occasions. Their goal is to con- tinue to meet the area's demands without interruption.
Section 111 DESCRIPTION OF EXISTING WATER DISTRIBUTION SYSTEMS Colorado River water is currently served to the City of Oceanside, the Carlsbad MWD, and Vista 1.D. through a series of pipelines fed by Pipeline No. 3 of the Second San Diego Aqueduct. 1975 peak-day water demands and peak-day factors for these agencies are presented in Table 1. In the existing system a number of reservoirs and storage tanks have been provided to meet peak flow requirements and agricultural supply. In spite of this storage the present system is currently reaching the point where it may be insufficient to supply the peak demands of some of the outlying elements of existing systems. While domestic water requirements are provided almost exclusively P by imported water, some of the agricultural water supply is provided by local water (37.5% in the Bueno Colorado MWD of which the Vista I .D. is a member) and through wastewater reclamation projects. Local water contribution to Oceanside and Carlsbad requirements is negligible.
Table 1 PEAK DAY WATER DEMANDS AND PEAK DAY FACTOR TRI-AGENCIES SERVICE AREA AGENCY PEAK DAY DEMAND (cf s) PEAK DAY FACTOR City of Oceanside Vista I.D. Carlsbad MWD 27.2* 2.0 Source: Annual Report, 1973, SDCWA * Present capacity of Carlsbad MWD is 25 cfs.
PROJECT DESCRIPTION
Section IV PROJECT DESCRIPTION PHYS ICAZ, DESCRIPTION The proposed Tri-Agency Pipeline alignment is shown in Figure 1. Segments of the pipeline are indicated by letter designation and are referred to in this discussion. The reader is directed to the pre- liminary engineering report conducted by the CWA in 1972 for detailed engineering description. Section AB (42-inch I.D. pipe) The proposed pipeline will connect to Pipeline 3 of the Second + San Diego Aqueduct at about station 2913 +50-, southeast of the city of Vista and near the intersection of the Second Aqueduct and Highway 78. Through a system of metering devices a single pipeline will proceed westward on 8th Street across Rancho Santa Fe Road and then southerly to La Mirada Road at the edge of Dunn School. The alignment proceeds westerly along La Mirada Road some 1,900 feet to point B. Total length of the segment is approximately 3,650 feet. At point B a 12-inch lateral line extends from the main trunk some 400 feet to the north along a road to an existing hilltop water storage facility (point C). This 12-inch line is the first of the supply lines to the Vista I.D. Section AB is designated to accommo- date a flow of 73.8 cubic feet/second (cfs) . Section BD (39-inch I.D. pipe) The alignment proceeds westward from point B along La Mirada Road (partially improved road -- dirt or gravel) to a point just east of
the Rancho 9ua Hedionda property line. At this point (D) a T-connection will be installed allowing a future 20-inch supply line south to the Vista I.D. Design flow in Section BD will be 68.8 cfs. Section DG (33-inch I.D. pipe) The alignment continues westerly from point D, entering and passing through the confines of an active gravel pit and concrete batching plant. Continuing westerly, the alignment enters the properties of Rancho Agua Hedionda. Near this property line the alignment leaves the areas of higher relief and enters a small valley to avoid a grove of oak trees. It follows a ranch road for some 600 feet to the approximate location of future Melrose Drive, point G. At point G a northwest-trending 18-inch lateral supply line some 6,100 feet long follows this proposed easement and other existing easements to the connection point for the V.D. (Point F). The design flow in Section DG is 52.6 cfs. Section GP (30-inch I.D. pipe) From G, the line continues some 350 feet where it leaves the ranch road and crosses Agua Hedionda Creek bed. It then proceeds up hill to point E, a T-connection for the future where an attachment for a third distribution line will be made. The line continues to the 500-foot contour and subsequently drops into a small valley draining south into Agua Hedionda Creek. The alignment then proceeds northwesterly along an existing powerline easement some 2,300 feet to near the summit of Coxey Hill. This section continues westerly over the northerly shoulder of Coxey Hill to the Agua Hedionda Ranch line (Point G-l), where a 24-inch lateral supply line extends south approximately 700 feet, the beginning of a future service line to supply water to the 400 acre- foot capacity Squires Reservoir. This section proceeds westward to point P, some 2,350 feet. At point P a 21-inch lateral line extends northward about 3,000 feet supplying an existing water storage facility on San Francisco Peak and the City of oceanside's system. Design capacity of Section GP is 38.0 cfs.
Section PT (24-inch I.D. pipe) From point P the alignment extends westward approximately 17,600 feet through the Carlsbad MWD to the western side of the El Camino Real (S-11) This section drops from about 400 feet to roughly 200 feet. Three existing water tanks (J,L,M) which are part of the Carlsbad storage system, will be tied into this alignment. Outlets for these possible lines will be provided. It is planned that future local residential water requirements will be tied directly to this line. Design flow in this line will be 20.0 cfs. Section TN (24-inch I.D. pipe) This final section of pipe will connect the line at the point it crosses the highway to the terminal point of the Carlsbad System running in a southerly direction paralleling the highway. This alignment was selected to provide the shortest practical route. To the degree pos- sible existing property lines are utilized. Interference with existing improvement or significant features was additionally considered in route selection. A number of ancillary facilities and structures will be required. A metering station will be constructed on the Second Aqueduct at station 29132, and will be confined entirely to the existing CWA right-of- way. The station will be used to control flow to the Tri-Agency Pipeline via throttling valves. Flow metering -devices and shutoff valves will also be installed. Metering stations will be provided at the point of delivery to each participating agency. These stations will be equipped with flow regulat- ing valves. U
A common metering and control station for both the CMWD and Oceanside will be located at point P. Metering stations are generally small concrete structures, low in profile. Other related structures will consist of blow-offs provided at the low points of all siphons (including energy dissipators and drainage conduits), air release valves at high points in the line, and 20-inch diameter access manholes at intervals of not more than 2,000 feet. Where these access outlets are not combined with blow-offs and vents they will be protected with mortar and buried. PROJECT COSTS The estimated cost of the project will be approximately $3.6 million based on 1974 prices. This cost will be borne jointly by the participating agencies according to the following percentages: Carlsbad Mn>, 43% or $1.57 million; City of Oceanside, 27% or $0.96 million; and Vista I.D., 30% or $1.07 million. Preliminary studies have indicated that the combination of the three agencies' requirements into a single pipeline will result in a cost saving of $1.5 to $2.0 million over the costs of three individual pipelines. At this point in time it is planned to finance the construction through bond issues. Construction Procedures Construction of the pipeline in the cross-country portions will re- quire the disturbance of an area approximately 60 feet in width. The procedure involves four steps. Initially the right-of-way is cleared of vegetation to provide access for the construction equipment and stock- piling of materials. Next, the trench is excavated to a depth of about 7 to 10 feet and excavated material pilediin mounds adjacent to the trench.
The width of the trench is dependent upon pipeline size, depth, and local soil conditions. A layer of coarse aggregate bedding is then laid in the trench and the pipe emplaced and connected to the previous- ly laid length. The trench is then backfilled and compacted with a minimum cover of 4 to 5 feet. Excess material is then evenly graded over the disturbed area, returning it to its natural configuration. Erosion control measures are employed and the area revegetated. In areas where rock is encountered, blasting may be necessary. Where watercourses are traversed, any existing flow will be divert- ed while the pipeline is laid below the streambed. At such points the pipe will be encased in concrete and buried deeper than typical to pre- vent erosion and preclude flotation. Pipeline constructed under public streets will not require as much heavy construction equipment as in the cross-country reaches since there is no clearing or grading involved. The amount of space disturbed will be less than 60 feet (about one-half the curb to curb pavement width). This reduction in operating space is accomplished by using shored verti- cal cuts in trenching, offsite storage of trenching spoil, and offsite storage of the pipe segments. As this requires hauling of trench materi- als from the site during trenching, and back to the site during backfill operations, the forward progress of the pipelaying operation is somewhat slower than open cross-country construction. Excess trench spoil can be used as fill in other projects and should not impose a load on existing disposal areas. The pavement of all street and highway surfaces excavated or damaged during construction will be restored in accordance with the regulations and specifications of (and subject to inspection of) the public authority having jurisdiction in each case. All driveways, private roads, and other facilities excavated or damaged during construction and not under
the jurisdiction of a public authority, will be reconstructed with the same type of materials as used in the original construction and to the same thickness and other applicable dimensions in such manner as to re- store the affected portions to a sound and serviceable condition. Any sidewalks, driveways, or private roads which have been removed for the purpose of construction shall have suitable temporary sidewalks, drive- ways or roadways emplaced and maintained in satisfactory conditon until final restoration is made. During the construction period it will be necessary to transport both personnel and material to the construction sites, and there will be a minor increase in traffic on some public streets. Upon completion of construction, a period of system testing will begin where the pipeline is tested prior to its integration in the over- all system. Operational Procedures A schematic diagram of the proposed Tri-Agencies Pipeline is shown in Figure 2. The proposed pipeline can be used by the three agencies in- volved for peaking by utilizing the existing storage facilities owned by Vista Irrigation District and Carlsbad Municipal Water District on a joint use bas is. Pechstein Reservoir, owned by Vista Irrigation District, has been particularly valuable due to its working elevation of 820 to 827 feet, which is above the required hydraulic gradient for most of the Vista Irrigation District system. This allows Vista Irrigation District to draw on this reservoir during peak demand, supplemented by the higher pressure water from the proposed Tri-Agencies Pipeline back-feeding the system. A 15 MG reservoir is planned to replace Pechstein in the future .
PI PEL1 NE 3 SECOND SAN DIEGO AQUEDUCT 5.0 -+ VISTA I. D. EX1 ST1 NG TANK 9 Ill FUTURE CONNECT1 ON VISTA I. D. rr) FUTURE CONNECT1 ON VISTA I.D. CV rr) I I 1 14.6 VlSTA1.D. EX1 ST1 NG SYSTEM Figure 2. SCHEMATIC DRAWING OF THE PROPOSED TRI-AGENCY PIPELINE 0 CO m 0 00 CY) SAN FRAI'qC! SCO PEAK 18.0 CITY OF QCEANS!DE SQUIRES RESV CARLSBAD MWD EX1 ST1 r\iG S'I'STEk 0 0 cv Figules Flow in cfs CARLSBAD MWD EX1 ST1 NG SYSTEM
During low use, water can be placed in storage from the Tri- Agencies Pipeline in reservoirs at devations above Pechstein Reservoir. When these reservoirs are at capacity, some excess flow in the Tri-Agencies Pipeline can be diverted to storage at Pechstein Reservoir. To accomplish this versatility, it is recommended that the control valves and meters at both Pechstein Reservoir and the Tri-Agencies Pipeline be equipped with supervisory control and remote flow indicators. Monitoring and control of the meters and valves should be accomplished from the Authority's Operations Center. Some of the peak demand on the aqueduct can be reduced by utilizing storage in Squires Reservoir, to be withdrawn by the lower lying areas in the Carlsbad Municipal Water District system during the periods of higher use. It appears that, by careful control of the systems, pumping can be virtually eliminated except when water is being placed in storage in the hFgher reservoirs.
URS Section V ENVIRONMENTAL SETTING TOPOGRAPHY The proposed project is located on the western flank of the north- western trending Peninsular Ranges. Terrain in the area is character- istically hilly with several small mesas toward the coastline. Eleva- tions range from nearly 650 feet near the connection to the Second San Diego Aqueduct to about 200 feet at the terminal connection to the Carlsbad MWD system. Drainage in the area is moderately well developed. The majority of the proposed alignment drains into Aqua Hedionda Creek which it crosses slightly east of its center. A portion of the western end of the alignment drains into Vista Creek. Both drainages terminate at the ocean wfth well-developed lagoons. GEOLOGY -GEOTECHNICAL SETTING General surficial geology is shown in Figure 3. The oldest rock outcroppings in the area are the Jurassic volcanics and metamorphics of the Black Mountain or Santiago series. These rocks have been intruded by plutonic rocks associated with the Southern California Batholith. The stratigraphic column is completed by a sequence of unmetamorphosed Cre- taceous, Eocene, Pleistocene sedimentary rocks whose thickness has been estimated at less that 4,000 feet (Hertlein and Grant, 1954). The follow- ing includes a brief summary of these geologic units.
- I0 0 i~-iHwl--4: 10 20 30 40 Miks i I0 0 I0 20 30 40 wk-trt -I I SO Kttometcrs Figure 3. GENERAL GEOLOGY 18
Figure 3 LEGEND EXPLANATION SEDIMENTARY ROChS - Alluvlurn Alluvrol- fon, flood-plorn, swamp, lake, ond dune depos,ts Dune sand I I Shodo rn coostol orecs only .................... :.<. ... ................... ....: -Q~:::..,::! :;::;;;.. .... ........... .,. .: .;. z .:::.,? Marine terroce de;)c~s~ts 1 Covered tn ploces by nclmcrrne I I depos!ts Terrace Geposnts tn cocstol oreos, older olluvrol- fan deposits ond OT~OSIC volley frll m ,.iterror oreos, ond lcke beds 87 lmperrol Vollrj, In port contcn~pcr ~iieids wrth mcrrne terrace depostts I Y 0, - L" * - a Pllocene morlne rocks Srltstone, sonr'stone, Idlocene and Pllocene and conglor erote nonmorlne rocks Pleistocene nonrnorlne deoos~ts Sondsione, conglom- erote, breccia, sl'tstole, cloy, ond luff, includes some M~ocene rnorrne rocks Plrocene rnorlne Sandstone, shc's, s~lt- rucks cod Plers - stone, conglcnerote, tocene conglomerofe ond breccrc rn lmperrol Volley I Tom I iJ Oligocene ~nd lower h!~scene rocks Sondsi-ne, s~ltstone, 0.13 conglom- erote, morrne rn upjer port only u Eocene morlne and ncnmortne rocks Sondstc7e, conplomero+e, old srlt- stone, upper port moln:y non- mor.)e in souttrern coos?al oreo u Paleocene nonrnorine and morlne rocks Sondsfcne, conglomerc!e, cloy, and lignrle; upper port morrne L.--J Cretoccous marine ond nvnmuririe rocks Congloncrote, sondstcrrc, Srl~stnne, ond shale; bosol port nuvmorme in Scntu An0 Nountoins METAMORPHIC ROCKS - Rocks tentatively assigned to the Frcnclscon group Schrsts, chert, Irmestone, and ossocroted bosrc Igneous rock! on Polos Verdes Hrlls ond Cotoltno lslond only Youyger metornorphfc serles Slate, sc'lrsts, quortrrte, omph~oolrts. conglomerate, ond Irmestone. I probably rncludes some olderrocks I Older rnetomorphlc rocks Schrsts, gnersses, phyllrte, quortrrte, and /,mestone, probob:y rncludes some younger rnetomorphic rocks. J U) IGNEOUS ROCKS Mornly meso-copprng flows, with loco/ pyroclosfrc moterrol rndeslte and bvsolt Solton Seo Doclte ond ouortz latlte '1 Smoll m!rusive mosses in coostcl oreo! 1 0 Plufoi~c cntruslve rocks of the 1 southern Col~fornia bottrollth , 5 Mornly tonolrte, gronodrorrte, o7d I gobbrogc rocks I Older plutonlc ond hybrtd rocks Mornly gronodiorrte and hybrrd gnejsses, rncludes older rocks west of Son Gorgon10 Poss Hypobyssol Intrusive rocks Mornly fme-grorned porphyrres of ,nternedrote composrtron, related to older volconrc rocks lzcl 11 Older volconlc rocks Metomorphnscd flow and pyroclostrc rocks of ondes~t~c to quart: lotrtrc composrtron J J
Pre-Tertiary Igneous and Metamorphic Rocks Rocks of the Black Mountain series consist primarily of dark- colored intrusive and effusive rocks of basic and intermediate composi- tion. They include andesitic and trachytic flows, agglomerates, tuffs, and metamorphosed sediments. These volcanic and metasedimentary rocks have been intruded by acid rocks including quartz diorite and bitite granite. No fossils have been found in these units. Cretaceous Rocks Cretaceous sedimentary rocks occur in limited outcrop along the coast. They consist of hard sandstones, shales, and conglomerates of both marine and nonmarine origin. The marine sequences are locally fossiliferous . Eocene Rocks Eocene rocks are represented by the La Jolla formation and Poway Conglomerate which are believed to be of middle or early upper Eocene age. These rocks are typically sandstones and siltstones, with some conglomerate. The upper parts are nonmarine. Marine microfossils and invertebrates are locally common, and some unique vertebrate localities have been found in the nonmarine sections. Pliocene Rocks The Pliocene is represented by the San Diego and Sweitzer forma- tions. The San Diego formation consists of yellowish and grey sand- stone and siltstone with some conglomerates. It is approximately Q50 feet thick and often contains excellent marine fossils. The Sweitzer
formation is a thin stratum of reddish-brown conglomerate and pebbly sandstone which commonly caps terraces south of Mission Valley. Pleistocene Rocks Marine fossiliferous Pleistocene deposits occur as terrace material in many coastal areas. Also encountered are deposits of gravel, sand, and silt of nonmarine origin in terrace deposits and deeper valley fill. Recent alluvium occurs in most of the present valley bottoms. Structure There has been relatively little folding in the younger rocks. The only major fold in the area is an asymmetrical fold northeast of Soledad Mountain. The younger sediments, which are of primary concern to this project, have been deposited on wave-cut benches in the older I rocks, and have experienced little deformation other than some minor tilting. There are no known major faults in the vicinity of the project. I Identified faults, as mapped by the California Division of Mines and Geology in 1971, are shown in Figure 4. Soils Soils within San Diego County have been mapped and described in de- tail by the Soil Conservation Service (1971). The reader is referred to this study for more detailed information. Generally the soils are coarse loamy decomposition products of the underlying rocks and are relatively thin in profile. Figure 5 depicts the approximate locations of various soil types in the vicinity of the pipeline alignment.
. . . . . . . . Fault, location projected - -- Fault, approximately located - Fault, location known Source: California Div. Mines & Geol . , 1971 (I URBAN GEOLOGY MASTER PLAN Figure 4. FAULTS
Table 2 summarizes certain data used in this environmental evaluation. Soil profile thickness, depth to hardpan, shrink-swell potential, ero- sion susceptibility, limitations for conversion of vegetation from brush to grass, and suitability of soils as a source of sand, gravel, or decomposed granite and suitability as topsoil are included. A certain degree of natural erosion of these soils will occur. Modification of the soil surface particularly as encountered during construction will generally accelerate the rate of this erosion, often impacting areas off-site. For this reason, the natural or background level of soil erosion in the area will be discussed. Although no known studies of sediment yield have been conducted on the project watershed, an indication of probable magnitude may be derived from a similiar ob- served area. In this case, data were available from the Soil Conserva- tion Service (Journal of the Hydraulics Division,American Society of Civil Engipeers, December 1972) for the San Juan Creek in Orange and Riverside Counties, some 30 miles to the north. The annual rainfall, slopes, land use, and geology in this area are similiar to the project area. Using reservoir sedimentation rates, an average sediment yield of 1.64 x cubic meters per square meter of surface area was obtained. Applying this factor to the area potentially disturbed by the project, it can be estimated that less than 50 cubic meters of soil are eroded annually, the bulk of which is deposited in the watercourse of the Agua Hedionda River. The bulk of this sediment movement can be expected to occur in a relatively few days during which high rainfall occurs. Landslides Landsliding is a relatively common problem in parts of San Diego County and has occurred in portions of existing water transmission systems. Figure 6 shows the approximate location of the project on a
Table L SOIL CHARACTERISTICS SOIL DEPTH SWELL- LIMITATIONS FOR SUITABILITY SUITABILITY PROFILE TO SHRINK CONVERSION FROM AS A SOURCE AS SYMBOL SOIL NAME THICKNESS HARDPAN POTENTIAL ERODIABILITY* BRUSH TO GRASS OF MATERIAL TOPSOIL Bonsall Sandy Loam, 2-9% slopes Bonsall Sandy Loam, 2-92 slopes, eroded Bonsall Sandy Loam, 9-15% slopes, eroded Carlsbad Gravelly Loamy Sand, 5-9% slopes Carlsbad Gravelly Loamy Sand, 15-302 slopes Carlsbad-Urbanland Complex, 2-92 slopes Cieneba Coarse Sandy Loam, 15-302 slopes, eroded Cieneba Coarse Sandy Loam, 30-65% slopes, eroded Cieneba Rocky Coarse Sandy Loam, 9-30% slopes, eroded Cieneba Very Rocky Coarse Sandy Loam, 30-752 slopes Diablo Clay, 2-92 slopes Diablo Clay, 9-152 slopes Diable Clay, 15-30% slopes. eroded Fallbrook Rocky Sandy Loam, 9-30% slopes, eroded Friant Rocky Fine Sandy Loam, 9-30% slopes Friant Rocky Fine Sandy Loam, 30-70% slopes Gaviota Fine Sandy Loam, 9-302 slopes Gaviota Fine Sandy Loam, 30-50% slopes Huerhuero Loam. 5-9% slopes, eroded Huerhuero Loam, 9-15% slopes Huerhuero Loam, 9-15X slopes, eroded Las Flores Loamy Fine Sand, 2-9% slopes Las Posas Stony Fine Sandy Loam, 5-9% slopes Las Posas Stony Fine Sandy Loam, 9-15% slopes, eroded Las Flores Loamy Fine Sand, 15-302 slopes, eroded Las Flores Loamy Fine Sand. 9-30% slopes, severely eroded Las Posas Stony Fine Loam, 30-652 slopes Loamy Alluvial Land, Huerhuero Complex, 9-50% slopes, severely eroded Marina Loamy Coarse Sand. 2-9% slopes Marina Loamy Coarse Sand, 9-30% slopes Salinas Clay Loam, 2-9% slopes Steep Gullied Lana Visalia Sandy Loam. 2-5% slopes Vista Coarse Sandy Loam. 5-9% slopes Vista Coarse Sandy Loam, 15-30% slopes High High High Low Low Low Low Low Low Low High High High Moderate Low Low Low Low High High High High Severe (9) Severe (9) Severe (9) Severe (2) Severe (2) - Severe (16) Severe (1) Severe (16) Severe (1) Slight Slight Moderate (1) Severe (16) Severe (9) Severe (1) Severe (I) Severe (9) Severe (9) Severe (9) Severe (9) Severe (2) Slight Slight Slight Slight Slight D. Granite D. Granite D. Granite Sand Sand Unsuitable D. Granite D. Granite Fair Fair Fair Poor Poor CbC CbE -1 ccc Severe Severe Severe Poor Poor D. Granite Unsuitable Poor CmrG Severe Poor DaC DaD DaE2 Slight Slight Slight Unsuitable Unsuitable Unsuitable Poor Poor Poor Moderate D. Granite Fair FxE Severe Unsuitable Poor Unsuitable Poor Poor Severe Unsuitable Unsuitable GaE GaF HrC2 Severe Severe Poor Severe Slight Slight Slight Slight Slight Blight Severe Moderate Severe Unsuitable Poor HrD HrD2 Unsuitable Unsuitable Poor Poor LeC Unsuitable Poor High Severe (2) High Severe (2) High Severe (2) High Severe (2) High Severe (1) Variable Severe (1) Unsuitable Poor Unsuitable Poor Unsuitable Poor Unsuitable Poor D. Granite Poor LrG Unsuitable LvF 3 M1C M1E SbC Low Severe (2) Slight Sand Poor Poor Fair - Good Fair Fair Low Severe (2) Slight Sand Moderate Moderate (2) Slight Unsuitable Unsuitable Unsuitable StG Va6 Variable Severe (1) Low Severe (16) Severe Slight vsc Low Moderate (2) Slight D. Granite VsE Low Moderate (2) Slight D. Granite * 1 = Slope 2 = Surface Layer Texture 9 - Depth to Hardrock (Hardpan) 16 - Grade of Structure in Surface Layer
LEGEND Q - Quaternary Sediments gm - Granitic/Metamorphic T - Tertiary/Tertiary Quaternary Sediments P - Paleozoic- Precambrian Rocks , Relative Abundance A most Source: D. H. Radburch & K .D. Crowther, 1970 Figure 6. ARUS OF RELATIVE AFiOUNTS OF LANDSLIDES Q
map indicating areas of relative amounts of landslides. Relative abundance is presented on an increasing scale of 1 to 6. As can be seen, most of the western county falls within the relatively low abundance zone 2. Seismicitv Figure 7 shows epicenters and magnitudes of earthquakes of magni- tude greater than 4.0 that have been historically recorded in Southern California. Earthquakes of magnitude less than 4.0 are not shown, but can be assumed to be much more abundant and more widely distributed than the larger earthquakes. No large earthquakes have been recorded as oc- curring within the Coastal San Diego area. The proximity of many epi- centers to a site is an indication that the site will probably be subject to similar earthquakes in the future and, conversely, their ab- sence from an area suggests a low likelihood of activity in at least the immediate future. , Neither the time or occurrence nor the size of an earthquake can be accurately predicted at present. Based upon past earthquake activity, probable size of future events can, however, be estimated. The detailed study of McEuen and Pinckney (1972) considers seismic risk to the San Diego area. They consider the Elsinore fault zone to be the source of maximum seismic risk to the San Diego area. The "maximum probable earthquake1' associated with this fault is of magnitude 7.3. Two other major fault zones exist to the northeast. The San Jacinto fault zone and the San Andreas fault zone are both north and east of the Elsinore fault. Large earthquakes originating along either of these faults could impact the project site.
URS Although it is reasonable to eliminate surface rupture as a potential hazard, damage may be incurred by transmission of seismic energy through rocks. Hard, firm rock, such as in the high areas under- lain by the Southern California batholith, is vibrated less than softer sedimentary rocks found in the terrace areas. Such soft rock may undergo seismic vibration several times that of hard rock. Very soft rock, such as alluvial fans, landslides, or stream deposits, may actually fail under seismic shaking. Mineral Resources A variety of metallic and nonmetallic mineral resources have been exploited in San Diego County. In the vicinity of the project site, mineral resources consist primarily of nonmetallic construction mate- rial, in particular sand and gravel. Sand and gravel production has generally increased, along with population growth, since the early 1900s, fluctuating to meet local demands. Some extraction of crushed rock and decomposed granite has taken place throughout the coastal area on a small scale intermittent basis. Sand and gravel have been extracted in the vicinity of the pipeline alignment near Green Oaks Ranch. unique Geologic Features Underlying bedrock, the foothills, and the mountains in western San Diego County are composed primarily of granitic materials. Unique fea- tures within these rocks are generally limited to unusual petrologic composition or internal structure of primary interest in research geology. Pegmatitic and other discordant bodies (dikes) also occur in association with these rocks. Most surface occurrences of these rocks are highly weathered and consequently low in quality, although a tourmaline-bear ing pegmatite locality exists north of the alignment. Excavations do expose unweathered material, and could expose new deposits.
The mesa areas are composed of sequences of Cretaceous (70 million years old) to recent sedimentary deposits. These rocks are predominant- ly of marine origin and locally may contain excellent fossil assem- blages. This is particularly true of the Eocene sandstones which have yielded excellent and unique fossils of fish, amphibians, birds and early mammals. Identification of fossil sites (localities) is in a very preliminary stage at this time. Sites are generally discovered in stream channels or during construction excavations where weathered overburden material has been removed. Unique landforms and geologic structures are generally less common in the mesa areas than they are in regions of higher relief or along shorelines in the county. No known unique geologic features or significant fossil localities have been associated with this project. ATMOSPHERIC ENVIRONMENT Climatology The climate of the project site and the surrounding region is typical of the San Diego Basin and can be described as coastal semi- arid subtropical. The prevailing weather patterns are in part tempered by the Pacific Ocean, with the result being that summers are cool and winters warm, in comparison with other places along the same general latitude (mean annual temperature of 60 - 62'). Winds are generally light (average speed of 7 mph) and mean annual precipitation is about 9 to 12 inches, with maximum rainfall during the fall and winter months, Atmospheric inversions (which are responsible for some of the worst instances of air pollution) occur frequently throughout the year.
Air Quality In general, the air quality in the San Diego Basin (within which the proposed project is situated) has been poor, especially with re- gard to oxidants and particulates. In fact, extreme measures have been suggested by the EPA in order that the San Diego area might comply with the 1975 federal air quality standards. However, heated controversy over these measures has markedly decreased the likelihood of their implemen- tation. As a result, it is quite likely that air quality within the region will get worse, not better, in the near future. Only with the initiation of control systems for both vehicular and stationary sources, which can effectively reduce or eliminate all pollutant emissions, will this trend be reversed. The San Diego Air Pollution Control District (SDAPCD) currently operates a six-station air quality monitoring network. From the data compiled by this network, it is possible to get a reasonably accurate picture of the current ambient air quality for the basin. Unfortunate- ly, while several of these stations (Oceanside and Escondido) are rela- tively close to the project site, monitoring of all the standard param- eters is not routinely conducted. Indeed, the closest complete monitoring station to the general project area is located in El Cajon. Because no complete ambient air data are available at the construc- tion site, it has been assumed that the ambient levels for the site are roughly similar to those at the El Cajon location. Data from this sta- tion for 1973 are presented in Table 3 and have been subsequently used fn evaluating the potential air quality impacts of the project. These data include annual averages for each major pollutant and the frequency of standard violation of these pollutants. National and state standards are listed in Table 4, and as noted in Table are most frequently exceeded at the El Cajon station by three particular pollutants: particulates, oxidants, and non-methane hydrocarbons.
Table 3 AIR QUALITY DATA SUMMAR.Y EL CAJON -- 1973 POLLUTANT PERCENT OF DAYS AVERAGE OF DAILY EXCEEDING STDS . MAX. HOURLY AVERAGES STATE FEDERAL 3 101(~) 55(b) Particulates (vg/m ) Carbon Monoxide (PP~) 3 0 1 Nitrogen Dioxide (ppm) .05 0 0 Sulfur Dioxide (ppm) Oxidants (pprn) Non-Me thane Hydro carbons (ppm) Source: Annual Report, San Diego County Air Pollution Control District, 1973 a. Average of all samples. b. Percent of samples at or exceeding the 24-hour standard.
Table 4 AMBIENT AIR QUALITY STANDARDS CALIFORNIA NATIONAL AVERAGING STANDARDS STANDARDS POLLUTANT TIME CONCENTRATION PRIMARY SECONDARY HAZARD Photochemical Oxidants (cor- 1 hour 0.10 ppm 160 ug/m3 Same as -- rected for NO ) 2 (200 pg/m ) (0.08 ppm) Primary Standard Carbon Monoxide 12 hour 10 ppm -- Same as -- (11 mg/m Primary 8 hour -- 10 mg/m Standards 73 mg/m 3 (9 PP~)~ (66 ppm) 1 hour 40 ppm 40 mg/m -- (46 mg/m (35 ppm) Nitrogen Dioxide Annual -- 100 ug/m3 Same as 24 hour: Average (0.05 ppm) Primary 4000 ug/m Standard (2.0 ppm) 1 hour 0.25 ppm -- (470 ug/m3) Sulfur Dioxide Annual -- 80 ug/m -- -- 3 Average (0.03 PPT) 24 hour 0.10 ppm 365 ug/m 260 ug/m 3 -- (263ug/m3) (0.14ppm) (0.10ppm) 3 hour -- -- 1300 ug/m3 -- (0.50 ppm) 1 hour 0.5 ppm -- -- -- (1310 uglm3) Suspended Annual 60 ug/m3 75 ~g/m 60 ~g/m 3 -- Particulate Geometric Mean 24 hour 100 %/m3 260 vg/m3 150 %/m3 -- Hydrocarbons 3 hour -- 160 ug/m3 Same as -- (corrected for (6-9 a.m.) (0.24 ppm) Primary Methane) Standard
HYDROLOGY/WATER RESOURCES The geographical area which this discussion shall focus upon is the "San Diego Region," as defined in the State Water Resources Control Board's "~omprehensive Water Quality Control Plan for the San Diego J Basin." This region includes all hydrographic basins draining into the Pacific Ocean between Laguna Beach and the California-Mexico boundary. The entire jurisdictional area and all of the facilities of the SDWCA and member agencies lie within the "San Diego ~egion." Figure 8 de- scribes the boundaries of the region, as well as various water resource elements such as streams, rivers, lakes, groundwater basins, reservoirs, and major water supply distribution facilities. Surf ace Waters Fresh surface waters within the San Diego Region include a variety of streams, rivers, lakes and reservoirs. Many of these lakes and reservoirs are used as water storage facilities for purposes of water supply There are eleven drainage basins, hereafter referred to as hydro- graphic units, within the San Diego Region. These hydrographic units are identified in Table 5, while their geographical location is speci- fied in Figure 9. Each hydrographic unit contains a stream system which eventually drains into the Pacific Ocean between Laguna Beach and the California-Mexico Border. The Tri-Agencies Pipeline lies within the Carlsbad hydrographic unit. The estimated mean seasonal natural runoff for each hydrographic unit within the San Diego Region is given in Table 6. As seen in this table, approximately 12,500 acre-feet of runoff is derived annually from the Carlsbad hydrographic unit.
Table 5 HYDROGRAPHIC UNITS OF THE SAN DIEGO BASIN NUMBER NAME 1 San Juan 2 Santa Margarita 3 San Luis Rey Carlsbad 5 San Dieguito Penasquitos San Diego Coronado 9 Sweetwater 10 Otay 11 Ti j uana
HYDROGRAPHIC 0 8 miles - Scale EXPLANATION - San Diego Basin Boundaries - Hydrographic Unit Boundary Figure 9. HYDROGRAPHIC UNITS OF THE SAN DIEGO BASIN
Table 6 ESTIMATED MEAN SEASONAL NATURAL RUNOFF FOR HYDROGRAPHIC UNITS WITHIN THE SAN DIEGO REGION RUNOFF HYDROGRAPHIC UNIT (acre-f eet) 1.0 San Juan 2.0 Santa Margarita 3.0 San Luis Rey 4.0 Carlsbad 5.0 San Dieguito 6.0 Penasquitos 7.0 San Diego 8.0 Coronado 9.0 Sweetwater 10.0 Otay 11.0 Tijuana TOTAL 331,400 Source: Comprehensive Water Quality Control Plan, State Water Resources Control Board, 1974
URS Surface drainage along the proposed route of the Tri-Agencies Pipeline is predominantly into the intermittent tributaries of Agua Hedionda Creek to the south, as dictated by topography. This drainage empties into the A~ua Hedionda Lagoon and ultimately into the Pacific Ocean. A small section of the route near the western end drains northward into Buena Vista Creek and Buena Vista Lagoon. These lagoons, both generally blocked from the ocean by barrier beaches, are significant in that they form a link in the Pacific (Gamebird) Flyway, and support unique floral and faunal populations. Because of their nature, waters within these lagoons is generally eutrophied. The quality of water in Agua Hedionda and Buena Vista Creeks is currently subject to a number of degrading influences including waste- water discharge, agricultural return flows, dairy operations, urban and construction runoff, and sand and gravel excavation operations. Bio- stimulation and eutrophication in the estuarine lagoons of these creeks have been a significant problem. Groundwater Occurrence of Groundwater All major drainage areas within the San Diego Region contain ground- water basins. Although they are of limited size, these basins have been historically important in the region, and in some portions of San Diego County have comprised the only source of water supply. The location of groundwater resources within the San Diego Region is shown in Figure 8. In the San Diego Region, groundwater is generally found within alluvial deposits, sedimentary units, and in residual mate- rials developed on crystalline rock. Also, groundwater occurs locally within fracture zones.
Well yields within the San Diego Basin generally range from a few gallons per minute to 2,000 gallons per minute. The total safe yield of major groundwater resources within the San Diego Basin is estimated to be about 150,000 acre-feet per year. No significant groundwater basins in the vicinity of the proposed project have been identified, although a significant portion of the water demand of the Vista Irrigation District is supplied from the groundwater basin at Warner Ranch. Imported Water Sources and Quantities of Imported Water The Metropolitan Water District (MWD) imports water from the Colorado River and California State Water Project, and subsequently supplies water to all or part of the following counties in Southern California: Los Angeles, San Bernardino, Ventura, Riverside, Imperial, Orange and San Diego. The MWD supplies water to the SDWA, whose jurisdictional area consists of the populated and agricultural areas of San Diego County. Presently, the MWD supplies only Colorado River water to the sWWA. The SWA presently receives about 350,000 acre-feet of water per year from the MWD, taking delivery at a point approximately six miles south of the Riverside-San Diego County line. The s~WA transports water through its jurisdictional area via two large aqueducts extending from the point of delivery to Otay Reservoir. The Tri-Agency Pipeline will be I connected to the dual pipelines of the Second San Diego Aqueduct. Quality of Imported Water Currently the SDEQW imports only unfiltered water from the Metropolitan Water District, on the order of about 350,000 acre-feet per year. ALL imported water is presently derived from the colorado River; however,
substantial amounts of California State Project water will be supplied to CWA by the MWD in the near future. Facilities are being designed by MMD and CWA to treat and transmit a blend of State Project and Colorado River waters. The existing quality of Colorado River water and State Project water is described in Table 7. Generally, State Project water is considered to be of relatively higher chemical quality than Colorado River water. Water derived from the Colorado River contains higher concentrations of total dissolved solids, hardness and alkalinity, whereas State Project water has more turbidity and color. The bacteriological quality of State Project water is rather poor. This is considered to be a significant problem, although treatment processes will adequately improve bacteriologi- cal quality. As seen in Table 7, water derived from the Colorado River does not meet recornended standards for drinking water as established by the United States Public Health Service. With regards to the four significant water quality parameters of Sulfate, Chloride, Nitrate and Total Dissolved Solids, State Project water meets the criteria for all of these parameters, whereas water derived from the Colorado River exceeds the recommended I limits for Sulfate and Total Dissolved Solids. . Wastewater Treatment and Disposal Wastewater in the San Diego Region is produced as a result of various domestic, commercial, industrial, and agricultural activities. In 1970, the region's total municipal wastewater flow (i. e . , wastewater accommodated by municipal treatment plants) consisted of about 122 million gallons per day. The 1970 emission of various pollutants discharged into the environ- ment within municipal wastewater effluent resembled the following:
Table 7 COMPARISON OF THE; WATER QUALITY OF WATER DERIVED FROM THE COLORADO RIVER AND THE STATE WATER PROJECT USPHS COLORADO RIVER STATE PROJECT RECOMMENDED PARAMETER WATER WATER LIMITS Calcium (mg/R) 8 7 40 -- Magnesium (mg/ R) 33 Sulfate (mg/~) 330 Chloride (mg/R) 100 4 5 250 Nitrate (mg/R) 0.9 0.6 45 Boron (mg/R) 0.11 Total Dissolved Solids (mglR) 751 Total Hardness as CaC03 (mg/~) 353 PH 8.2 Color 5 Turbidity (J.T.u.) 1.3 Temperature (OF) 63 * Reflects short-term effects of local runoff.
Biological Oxygen Demand Total Dissolved Solids 1,800,000 lbslday Total Suspended Solids 86,000 lbslday Future daily flows of municipal wastewater will increase due to in- creased urban activity and population growth. However, the loads of pollutants discharged into the environment are anticipated to decrease due to the introduction of more sophisticated treatment processes within the region. Most effluent from municipal wastewater treatment plants is dis- charged into the Pacific Oceanthrough numerous outfalls. A few of the smaller plants discharge their effluent at inland locations. In the project area, the Encino Water Pollution Control Facility (Joint Powers Plant) presently provides primary treatment and receives untreated wastewater from the Vista S.D., the City of Carlsbad, the Buena S.D., and the San Marcos CWD. Treated waste is then discharged through an ocean outfall. The plant in 1973 accommodated an average annual flow of 4.6 mgd. Although a number of wastewater reclamation plants operate in San D'Lego Co~mty, relatively little demand for reclaimed water exists in the Encino (or project) area. Besides the aforementioned point sources of wastewater, there are also a variety of non-point sources of wastewater produced in the region, such as urban and agricultural runoff. Urban runoff has been shown to contain significant amounts of oxygen-demanding material and heavy metals, whereas agricultural runoff often contains nutrients and pesticides. Presently, non-point sources of wastewater in the region are essentially uncontrolled, i.e., receive no treatment. r
BIOLOGICAL SETTING Flora The vegetation occurring in the proximity of the pipeline alignment will be discussed in terms of plant communities. Field studies and air photo interpretations were conducted as part of this impact assessment to locate and map major plant communities and record the presence of rare or endangered species. The vegetation surrounding the pipeline alignment is a mosaic of coastal scrub/chaparral, and grassland communities. The general distri- bution of these communities is shown in Figure 10. Also indicated on this figure are domina2t vegetative types within these communities. Table 8 lists the flora typical to these communities and rare or endangered plant species which could be encountered. Much of the grasslands now occupying the pipeline alignment and ad- jacent areas have been recently disturbed by livestock grazing and vehicu- lar travel. The natural grasslands of the area are dominated by native perennial bunchgrasses, with many associated wild flowers. Cattle and sheep grazing have caused a change in dominance from native perennials to introduced and native annual grasses. In the more protected areas or those areas with a better quality of soil, the grassland community has recovered to a condition superficially resembling the native state. An extensive grassland area presently exists from the base of Coxey Hill to Santa Sinforosa Ridge. In the grasslands near the developed areas of Vista and Carlsbad an assortment of plants commonly associated with disturbances was observed. These include introduced annual grasses and herbaceous plants.
Table 8 FLORA TYPICAL TO COASTAL SCRUBICWARRAL AM) GRASSLAND COMMUNITLES Coastal 'Scrulj/Chauarral Manzanita (several species) Hard Tack (Birch-leaved Mountain Mahogany) Toy on Lemonade Berry Chamise Buckwheat (several species) Red berry Coast Goldenweed Buck Brush Coast Live Oak Ceano thus Sycamore Sagebrush (several species) Grassland Wild Oats Star Thistle Russian Thistle Wild Mustard Barley Brome grasses Tarweed (several species) Possible Rare or Endangered Species Otay Manzanita (Acctostaphylos otayensis) Small-flowered Mountain Maho~anv (Cercocar~us minutiflorus) v # - Tarweeds (Hemizonia con jugans and H . f loribunda)
The coaetal scrublchaparral community dominates the pipeline corri- dor through Rancho %ua Hedionda and the area extending from Santa Sinfo- rosa Ridge to Carlsbad. The sage scrub averages approximately four feet in height and is relatively undisturbed in general appearance except around existing ranch houses, truck farms, and small livestock areas. The scrub/grassland communities provide feeding grounds and habitats for the fauna of the area. Additionally, coastal scrub and chaparral plant communities have extensive root systems and are effective in con- trolling runoff and soil erosion. Two established oak groves and one eucalyptus grove lie within the pipeline easement. One of the oak groves occupies the area west of the sand and gravel pit, and extends to Green Oaks Ranch. The second oak grove and the eucalyptus grove are located within the properties of Rancho %ua Hedionda. The proposed pipeline alignment has been selected to avoid interfering with these groves, and it is anticipated that only two trees will require removal. The Rancho Agua Hedionda represents an area of high ecological sensi- tivity. The interface between the established oak grove, the coastal scrub, and grassland creates an extremely productive environment for a host of raptors, small mammals, and reptiles. The grassland meadow area consists of heavily grazed grasses and "Coast Goldenweed" (Maplopappus venetus). The oak woodland is composed primarily of the California Live Oak, Quercus agrifolia. The Western Sycamore, Platanus racemosa, adds to the floral diversity along the creek. I The oak woodlands of both sites are well established. The trees range in height from 20 to 50 feet with well-developed, dense canopies. The trees are well spaced, allowing easy travel access for large mammals and roost areas for raptors. The eucalyptus grove, the middle section of
which will be removed during construction, is located on the north end of Rancho 9ua Hedionda. This grove of well-established trees is approx- imately four trees across, 200 yards long,and oriented in an east-west direction. The grove has been disturbed on the south side by a ranch road and by clearing for agricultu2al use on the north side. The grove may have been originally planted as a wind break. No rare or endangered species were encountered during the field work. Wildlife The wildlife observed is generally typical of the coastal scrub/ grassland plant community. Wildlife typical to the areas are listed in Table 9. However, additional bird activity, especially raptors, was noted around the oak and eucalyptus groves. The density of the sage scrub vegetation is generally non-restric- tive to the smaller mammals and reptiles; however, the dense scrub area west of Santa Sinforosa Ridge could restrict movement of large mammals. Numerous mammal burrows and trails were noted among the sage scrub. Wood rat (Neotoma sp.) droppings were in abundance on p;otected rocky areas. Rabbit droppings were noted mainly at the interface of the grass- land and scrub plant communities. The oak and eucalyptus groves are the nesting area for numerous birds, especially raptors. Three Red-Tail Hawks (Buteo jamaicensis) -- were observed in the Rancho Agua Hedionda oak grove during the field work. The groves are surrounded by grasslands rich in small, burrowing mammals and reptiles serving as the raptors' food source. Although not ob- served, the endangered Kangaroo Rat (Dipodomys ste~hensi) may be encoun- tered in the project area. This is the only rare or endangered specie of identified possible occurrence in the local area.
Table 9 WILDLIFE TYPICAL TO PROJECT AREA Mammals Jack rabbit Audubon Cottontail Brush Rabbit California mouse (Peromyscus) Pocket Mouse White-Footed Mouse Deer Mouse Sage Sparrow Lazuli Bunting Wrentit Ash-Footed Flycatcher California Thrasher Towhees California Quail Cactus Mouse Wood Rat Pocket Gopher Kangaroo Rat* Bob Cat Grey Fox Coyote Raccoon Birds Mourning Dove Rock Dove Logger-headed Shrike Whitetailed Kites Red-shouldered Hawk Red-Tail Hawk Burrowing Owl Barn Owl Western Fence Lizard Striped Racer Western Rattlesnake San Diego Gopher Snake Southern Pacific Rattlesnake King Snake * Endangered
NOISE ENVIRONMENT The route of the proposed Tri-Agency Pipeline has a variety of noise environments that need to be considered. Critical definitions and signif- icance of findings are presented in Appendix A. The pipeline covers a distance of about 10 miles, encompassing rural, suburban and residential areas. In each of these cases, a different range of noise environments exists. The postulated ambient noise environment can be expected to vary from 25 to 45 dBA in rural areas, 30 to 50 dBA in suburban areas, and 40 to 60 dBA in residential areas. ARCHAEOLOGY AND HISTORIC STRUCTURES A survey of the partially cleared proposed alignment for the Tri- Agency Pipeline was conducted during October, 1974 by members of URS and qualified local consultants. The consultant report appears as Appendix B. In the vicinity of the tentative corridor, five sites of archaeologic re- mains were discovered. Four of the sites lie within the corridor. An additional site, a stonelearth defensive wall, lies south of the tenta- tive alignment. Of the four corridor sites, three may be of value for their preserved archaeologic remains. No survey of the future service area of the pipeline was conducted, although the corridor survey may be considered an indication of possible occurrences in areas. Assuming that the tentative alignment of the pipe- line was not chosen for features which may be strongly correlated with those determining archaeologic occurrences, the presence of five archaeo- logic sites in and near the alignment suggests that perhaps fifty (50) sites, or even more, could be included within the service area of the water from the pipeline.
VISUAL AND AESTHETIC SETTING The existing visua1 characteristics of the proposed pipeline align- ment are governed by topography, vegetation patterns, and land use. The majority of the route is dominated by scrub- and granite outcrop-covered rolling hills. These areas are relatively undisturbed, although they are crossed by access and maintenance roads and transmission lines. Toward the eastern end of the route and in the larger stream valleys flat grass- lands dominate. Numerous oak groves occur in this region. A large part of this latter area is the private property of Rancho Aqua Hedionda. Urban and residential development occurs at both ends of the pipeline. Due to the topography, trees, and restricted access, viewshed of or from the project alignment is limited. Long distance views and ex- posure are, however, attainable where the route crosses hilltops and at other areas of higher elevation. While there are no individually outstanding visual features on the property, many feature,s such as the oak and eucalyptus groves, spring wildflowers and secluded drainages are both attractive and relatively unique in their own way. Additionally, a number of interesting and contrasting features are presented. These include the vegetation, color, and textural differences between the grasslands, brush, and wooded areas and the land-use contrast between the relatively undeveloped hills and the semideveloped "bottom lands." SOCIOECONOMIC SETTING The geographic area defined for planning and analysis purposes for the pipeline includes the incorporated cit,ies of Oceanside, Carlsbad, Vista, and unincorporated County of San Diego territory. The Comprehen- sive Planning Organization of the San Diego Region (CPO) hiis prepared
numerous studies, forecasts, and plan elements in cooperation with the County of San Diego and the 13 member incorporated cities. Community Subregional Areas have been defined for data analysis purposes, which are combinations of Census Tracts as delineated by the 1970 census. These Statistical Community Subregional Areas include Oceanside tistical Area #44) ; Carlsbad (Statistical Area #43), and Vista (Statis- tical Area #47). These three Statistical Subregional Community Areas in combination are nearly coterminous to the present territory served by the combined Tri-Agency water districts. Present Socioeconomic Profile The present socioeconomic profile of each Community Subregional Sta- tistical Area (which is nearly coterminous with the Tri-Agencies service territory) is summarized in Table 10. The data are for the base year 1973, as computed by the Comprehensive Planning Organization of the San Diego Region. The Community Statistical Subregional Areas combihed had a total gross land area of approximately 80,273 acres. The total Tri-Agencies area population of 107,996 persons in 1973 lived on about 13,122 acres of developed residential land, with a popula- tion density of six persons per net residential acre. The net residential density (number of housing units per acre of residentially developed land) was 2.1 housing units per acre.
Table 10 1973 STATISTICAL PROFILE OF THE SOCIO- ECONOMIC CHARACTER OF THE TRI-AGENCIES SERVICE AREA AND COMMUNITY STATISTICAL SUBREGIONAL AREAS 1'143 844 1'147 TOTAL TRI-AGENCIES CARLSBAD OCEANSIDE VISTA AREA POPULATION Median Income $ TOTAL HOUSING UNITS 7,186 18,603 12,005 37,794 Single Family Units 4,964 13,511 10,488 28,963 Multiple Units 2,222 5,092 1,517 8,831 EMPLOYMENT 6,378 13,725 5,864 25,967 Basic 1,523 3,284 1,470 6,277 VI Local Serving 4,855 10,441 4,394 W 19,690 LAND AREA (acres) 25,639 28,632 26,002 80,273 Residential Use 2,212 4,341 6,569 13,122 Basic Employment Uses 236 39 2 195 823 Local Serving Employ. Uses 649 1,282 351 2,282 STREETS 349 2 45 326 920 VACANT 18,723 17,507 11,122 47,352 UNUSABLE 3,470 4,865 7,439 15,774 Population per Housing Unit 2.98 2.80 2.86 2.85 Net Residential Density (HUs > 3.2 4.3 1.8 2.10 acre Ratio of Basic Employment .24 .24 .25 .24 % Single Family to Total Housing 69 .I% 72.6% 87.4% 77.6% % Vacant Land of Total Area 73.0% 61.1% 42.8% 59 .O% Source: Comprehensive Planning Organization, PLUM data, 6/27/74
Population per housing unit for the total Tri-Agency area was 2.85 persons per unit. Median income in current 1973 dollars for the Tri-Agency area was $9,598. Urbanized land, i.e., residential, basic and local-serving employ- ment land uses, and streets, covered 17,147 acres out of 80,273 acres. Present urbanization utilizes over 21 percent of the total land area. It should be noted .that 47,352 acres were classified as "vacant," and therefore potentially available for future urbanization. Thus, 59.0 per- cent of the total Tri-Agency Area presently considered vacant could be urbanized in the future. Only 15,774 acres, or 19.7 percent of the total land area, was considered "unusable" for future urban development. Of the present 37,794 housing units in the Tri-Agency Area, 76.6 percent were single-family units, and only 23.4 percent were classified as multiple units. This is a very high ration of single family housing. Total employment as estimated by CPO in Tri-Agencies Area was about 23,967 jobs in 1973. Of this total, 24 percent were classified as "basic" employment, and 19,690 jobs, or 75.8 percent, were classified as 11 local-serving" employment. Employment density for the Tri-Agency Area was 12.7 employees per acre for "basic" employment land uses, and 4.1 employees per acre of "local-serving" employment land uses. Local-serving land uses, i.e., retail trade, business services, retail services, public schools and other, are more intensive users of land in terms of employment density than is "basic" employment industry which tends to use land in more spacious or extensive site sizes.
Streets and roads utilized only 7.0 percent of the total urbanized land uses. Of the four Community Statistical Subregional Areas, the Oceanside Area had the largest 1973 population -- 52,182 persons -- and encompassed the largest land area -- 28,632 total acres. The Oceanside Area had the highest net residential density (4.3 housing units per residential acre of land use), and the lowest median income ($8,433). The Oceanside Community Area had 18,603 housing units in 1973, and 13,511 were single family units, total employment was 13,725 jobs of which 10,441, or 76 percent, were "local-serving." Population per acre of residentially used land was 12.0 persons per acre. Basic employment density in the Oceanside Area was 8.4 employees per acre of basic employmknt land uses, and 8.1 employees per acre of local- serving employment land uses. Out of 28,632 acres in the Oceanside Subregional Community Statistical Area, 61.1 percent or 17,507 acres were vacant, and therefore potentially available for future urban development. 4,865 acres were classified as 11 unusable." In the Oceanside Area, 6,260 acres, or 21.9 percent of the total land area, were in urban land uses during 1973; of this acreage 69 percent was in residential uses, and only 4.0 percent was utilized by streets. The Carlsbad Statistical Community Subregional Area (ji43) encompassed approximately 25,639 acres of land, and had a 1973 population of 21,442 persons.
Total housing units in the Carlsbad Area totalled 7,186 units upon 2,212 acres of residential land. This represented a net residential density of 3.2 units per acre. Population density was 9.7 persons per acre of resi- dentially used land. Median incomes in the Carlsbad Area were the highest of all three com- munities -- $11,700 in 1973 dollars. \ Nearly 70 percent of the total housing units in the Carlsbad Area were single-family units. Seventy-three percent of the total land area of the Carlsbad Statisti- cal Community Area (1143) was classified as vacant in 1973. This means that approximately 18,723 acres of land are considered potentially developable in the future for urban purposes. Only 3,470 acres were classified as "unusable. l1 , Total employment in the Carlsbad Area was 6,378 jobs in 1973, of which 1,523 were "basic" employment jobs, and 4,855 were "local-serving1' jobs. Basic employment density in the Carlsbad Area was 6.5 employees per acre of "basic" employment land use, while "local-serving" employment density was 7.5 employees per acre of such local-serving employment land utilization. The Carlsbad Area has the greatest capacity for future population and urban development growth, and with a higher quality and higher income level potential of the three community areas served by the Tri-Agency water serv- ices jurisdictions. The Vista Community Statistical Subregional Area (#47) contained a total land area of approximately 26,002 acres, with a 1973 population of 34,372 persons.
The population resided in 12,005 housing units, of which 10,488 were single-family. Single-family units represented 87.4 percent of the total housing stock. Residentially used land comprised 6,569 acres; thus the net residential density of 1.8 housing units per acre made Vista the low- est density community. Average site size per housing unit in the Vista Area is more than one-half acre. Population density was 5.2 persons per residential acre. Median incomes in Vista were $8,661, substantially lower than Carls- bad but slightly higher than for Oceanside. Total employment in the Vista Community Area was 5,864 jobs, of which 25 percent, or 1,470 jobs were classified as "basic" and 75 percent, or 4,394, were classified as "local serving." Basic employment land uses consisted of 195 acres, at an employee density of 7.5 employees per acre. Local serving employment land uses con- sisted of 351 acres, at an employee density of 12.5 employees per acre. Of the 26,002 acres of land area in the Vista Community Statistical Subregional Area (#47), 11,122 acres or 42.8 percent of the total were classified as ffvacantll and therefore potentially available for future urban development. 7,439 acres were classified as "unusable." In 1973, 7.441 acres were in urban uses; 88.3 percent of this was classified as residential land uses. Only 326 acres or 14.4 percent of the urbanized land was devoted to streets in the Vista area -- a very low ratio of street acreage. The pattern of urban development in the Vista Area indicates a very low density, semi-rural character, with families of moderate income.
Table 11 SUMMARY OF 1971 LAND USE BY MAJOR CATEGORY, CITIES OF CARLSBAD, OCEANSIDE, AND VISTA INCORPORATED TERRITORY CARLSBAD OCEANSIDE VISTA LAND USE CATEGORY ACRES % ACRES % , ACRES t RESIDENTIAL 908 11.0 2,317 10.6 I 1,924 Spaced Residential (1 acre or more) 333 4.0 480 2.2 110 Single Family Residential 489 5.9 1,403 6.4 1,589 Multi-Family Residential (2 or more units per structure) 7 2 .9 263 1.2 137 Mobile Home Parks 14 .2 171 .8 8 8 COMMERCIAL 117 1.4 265 1.3 150 ul co Retail, Wholesale, Professional & Services 6 7 .8 233 1.1 145 Shopping Centers 50 .6 32 .2 5 INDUSTRIAL 76 Manufacturing, general 9 Aircraft Ordinance & Electrical Machinery 15 Extractive, Mining 52 BU3LIC AND C)UASI-PUBLIC 16060 Government Institutions, Churches, Schools, Cemeteries 9 2 Transportation, Communication, Utilities 829 Public & Quasi-Public Recreation, Parks, Golf 9 4 Other Recreation -- Commercial & Sports 45 ALL CITIES % ACRES %
Table 11 SLJMMARY OF 1971 LAND USE BY MAJOR CATEGORY, CITIES OF CARLSBAD, OCEANSIDE, AND VISTA (Continued) INCORPORATED TERRITORY CARLS BAD OCEANS IDE VISTA ALL CITIES ACRES % ACRES % ACRES % ACRES % AGRICULTURE 1,109 13.5 3,395 15.6 539 7.6 5,043 13.6 Orchards 97 1.2 1,219 5.6 345 4.9 1,661 4.5 Truck Crops, Nursery, Poultry, Livestock 1,006 12.2 76 .4 150 2.1 1,232 3.3 Grain, Pasture & Fallow Lands 6 .1 2,100 9.6 44 .6 2,150 5.8 OPEN SPACE & MILITARY 4,980 60.4 12,919 59.3 3,293 46.3 21,192 57.1 National Forests & Undeveloped State Parks 161 2.0 1 0 0 0 162 .4 Military Bases/Lands & Indian Reservations 0 0 0 0 2 0 2 0 Reservoirs, Lakes, Bays, Lagoons Undeveloped & Unused Lands TOTAL LAND USES - ALL CATEGORIES Source: San Diego County and Comprehensive Planning Organization
Table 11 presents the detailed tabulation of specific land uses for the year 1971 for each of the incorporated cities of Oceanside, Carlsbad and Vista, and the combined acreages for all cities. These data were compiled by the County of San Diego Planning Department and the CPO in cooperation with the cities. The total territory encompassed by the combined incorporated cities in 1971 was approximately 37,145 acres out of the Tri-Agencies served com- munity subregional statistical area total of 80,273 acres. Consequently, in 1971, 43,128 acres were under the planning and zoning jurisdiction of San Diego County. (Recent annexations, notably by Carlsbad and Oceanside, have significantly changed the incorporated land areas.) I Of particular significance, however, is the fact that out of an in- corporated land area of 37,145 acres for all three cities, 20,279 acres -- or 54.6 percent of their combined territory -- were classified as "un- developed and unused" lands -- thus potentially available for future urbanization. In addition, 5,043 acres or 13.6 percent of incorporated territory was in Agricultural use -- also potentially convertible into urban land uses. Nearly 25,500 acres within present city boundaries (1971) were non-urban. Only 10,910 acres were in actual urban use out of 37,145 acres incorporated -- 29.4 percent. As noted in previous sta- tistics, the overall density of development is quite low -- generally semi-rural, and certainly at suburban (relatively large lot) single- family residential standards. By increasing densities moderately, to say 7.0 housing units per net residential acre, and using clustering layout design concepts to minimize street acreages, a typical housing unit might require an aver- age of only 6,000 square feet of site land area. At that density, the 20,279 acres of undeveloped and unused lands, less perhaps 25 percent as being too steep for development or undesir- able for development, would yield about 15,000 developable acres
within the 1971 incorporated territory. Deducting another 25 percent for streets, new parks, additional schools, shopping, ~ff ice, business and industry would yield 11,500 acres for new residential. At 7.0 housing units per net acre, this would accommodate 80,000 new housing units. Assuming an average population of only 2.8 persons per unit, an additional 223,600 people could be accommodated within the three areas. The total population in 1995 as projected by the CPO for the com- bined community subregional statistical areas is only 180,054 persons compared to 107,996 persons in 1973. Thus the total forecast INCREASE or net growth in population for the 22-year planning period is only 72,058 new people. Planning for the Future--Projected and Planned Growth Until 1947, when San Diego County's population reached about 500,000, local water sources were sufficient to provide the necessary supplies for domestic, industrial, and agricultural needs. However, 1947 was a critical water supply year. The importation of Colorado River water that year through the just completed First San Diego Aqueduct averted a serious shortage crisis within days of an actual deficiency. The San Diego Aqueduct Project was the result of foresight and vision by local San Diego County area community leaders. These same people were instrumental in creating the San Diego County Water Authority in 1944 as a member water wholesaling agency within the Metropolitan Water District of Southern California. Since 1947, three additional pipelines have been constructed by the Authority to transport Colorado River water. This water distribution
system has provided for the water demands of urban growth during the past 25 years in San Diego County. The current population of San Diego County (November, 1974) is esti- mated at approximately 1,550,000 (URS' estimate, based upon discussions with the Comprehensive Planning Organization, San Diego Chamber of Com- merce, and other sources). The growth of population in San Diego County since the mid-1940's has been caused primarily by in-migration. Although the military impacts of World War I1 greatly expanded the county's population level, it was after 1950 and the Korean War that San Diego County was exposed to thousands of military personnel and their families. This national exposure helped to create a strong desire among non-Californians for living and working in San Diego County. Coupled with military and defense-related job oppor- tunities, a "migrationff momentum, which led to further growth, was created. Promotional activities and enterprising developers further sold thousands of Los Angeles Metropolitan Area residents on the climatic, scenic, air quality and life style benefits and amenities of San Diego County. As a result, county population doubled during the 19501s, and increased by near- ly one-third during the 1960s. Rapid population growth has continued so far into the 1970s, and is expected to continue Snto the 1980s and 1990s -- barring unusual economic or catastrophic events, breaks in established forces/trends, or the imposition of radically restrictive anti-growth de- velopment policies. The Tri-Agencies water service area, and the cities of Oceanside, Carlsbad, and Vista, have all participated in the past growth of San Diego County and will participate in future regional and local growth. Planning and forecasting regional and subregional population and urban growth is the responsibility of the Comprehensive Planning
Organization of the San Diego County Region, in cooperation with the County and the member 13 cities, including Oceanside, Carlsbad, and Vista. The CPO functions as the Council of Governments formed in order to assure a sound overall area-wide planning process coordinated for the optimum future benefit of the entire region. CPO is the "A-95" clearinghouse for regionwide intergovernmental cooperation on the spending of federal funds in a manner consistent with local and state governmental needs. Circular A-95 (Revised) is promulga- ted by the Executive Office of the President, Office of Management and Budget . As the joint, cooperative planning and review agency for the San Diego Region, CPO through the Circular A-95 process seeks to aid local governmental agencies in the most efficient use of federal and state grant funds to further carry out agreed upon local and regional objec- tives. As of January 1, 1974, Circular A-95 requires that approximately D 140 categorical grant programs and special revenue sharing programs be reviewed by the regional clearinghouse organization. Thus, any agency seeking federal funds or assistance, including private firms developing housing subdivisions of 25 lots or more as an FHA-or VA-insured project, must be reviewed by CPO. The CPO is preparing a Comprehensive Plan for the San Diego Region, in cooperation with San Diego County, the 13 incorporated cities, and various other jurisdictions/special districts. CPO is and has conducted numerous studies, developed data systems, and has prepared selected ele- ments of the Regional Plan. Of course, each city and San Diego County presently exercise their own powers over land use, zoning, and other planning matters. CPO's power is currently advisory, except for the A-95 review process in respect to projects obtaining federal aid. P In the future, legislation may be enacted to expand the regional power of CPO or a successor agency to control land use, transportation, growth and environmental planning for the entire area.
Major studies and plan elements completed to date which have a bearing on future development include the Open Space Plan; Water, Sewerage and Flood Control Systems Plan and Implementation Program; Regional Development Goals and Objectives; and the Analysis of Regional Development Alternatives. The baseline data for these studies and plan elements have been the forecasts of future population, housing needs, and land requirements under various density and distribution pattern assumptions. To date, the "Controlled Trends Regional Develop- ment Alternative" appears to be the planning concept framework most like- ly to be implemented with conscious policy declarations and action pro- grams to guide the future pattern of urbanization in the San Diego County Region. Within this regional context, the forecasts of future populations, land use, housing units, employment, and other basic planning statis- tics have been compiled for the Tri-Agencies water service area and the community statistical subregional areas of Oceanside, Carlsbad, and Vista. Figure 11 depicts the projected population from 1973 to 1995 for the San Diego County Region, the Tri-Agency water service area, and each of the community statistical subregional areas. Table 12 presents basic projected planning statistics from 1975 to 1995 for the Tri-Agency water service area (coterminous for analysis purposes with the community statistical subregional areas). As the growth curves of projected population revea1,as depicted on Figure 11, the Vista and Carlsbad areas are expected to grow at a higher rate than the San Diego County region; so is the total Tri-Agency water service area. The Oceanside area is projected to grow at a rate similar to the entire region. The rate of growth between 1990-1995 is expected to decline.
i 1 , PROJECTED POPUZATION, 1973-1995: SAM DIECO COUPJm REGION, TBI-AGENCY SERVICE AREA, 6. STATISTXU AREAS
Table 12 BASIC PROJECTED PLANNING STATISTICS-1975-1995 TRI-AGENCY SERVICE AREA - COMBIWD COMMUNITY AREAS POPULATION 113,700 129,204 144,977 163,960 18n ,nsh MEDIAN INCOME (in constant 1973 dollars) 9,842 10,507 11,204 11,283 11,371 TOTAL HOUSING UNITS 38,951 46,654 54,434 63,365 72,683 Single Family Units 29,638 34,172 38,766 44,020 49,522 Multiple Family Units 9,313 12,482 15,668 19,345 23,161 EMPLOYMENT Basic and Local- Serving 30,472 36,695 42,998 50,139 57,609 URBANIZED LAND In acres 17,838 21,343 25,135 27,438 29,933 VACANT LAND In acres UNUSABLE LAND 15,774 15,774 15,774 15,774 15,774. TOTAL LAND AREA (acres) % URBANIZED 22.2% 26.6% 31.3% 34.2% 37.3% % VACANT 58.1% 58.3% 49 .O% 46.2% 43.1% EMPLOYMENT PARTICIPATION RATIO 26.8% 28.4% 29.7% 30.6% 32 .O% % MULTIPLE HOUSING UNITS 29.9% 26.8% 28.8% 30.5% 31.9% -- POPULATION PER HOUSING UNITS 2.92 2.71 2.66 2.59 2.48 Source : Comprehensive Planning Organization hh
Total population, median income (in constant 1973 dollars), hous- ing units, employment, and land uses are also shown in Table 12 for the Tri-Agency area. A further refinement of such planning statistics is shown for each of the community subregional statistical areas for the period 1975-1995 on Table 13. Table 14 shows population projections by census tracts comprising the community subregional statistical areas. All data are from the PLUM (Population and Land Use Model) data projections prepared by the CPO. The census tract statistics show which specific geographic areas within each community statistical area are expected to experience ex- tensive urban development and housing unit construction activities dur- ing the 20-year planning period. In analyzing the projection data presented in those tables, the following facts are relevant concerning future growth in the Tri-Agency service area and the component community statistical areas: e Of the approximate 80,270 acres of land encompassed by the Tri-Agency service area, 22.2 percent, or 17,820 acres are expected to be urbanized by 1975; in 1995, 29,941 acres or 37.3 percent of the total area are expected to be urbanized. 1975 population for the Tri-Agency area is estimated at 113,700 persons; by 1995, population is projected to increase by 66,354 persons to a total of 180,054. e Median incomes, in terms of constant 1973 dollars, are expected to increase from $9,842 in 1975 to $11,371 in 1995 within :he total Tri-Agency service area. e Nearly 60 percent of the land area is classified as vacant in 1975; by 1995, only 43.1 percent of the land area, or 34,566 acres, is projected to still be vacant and therefore potentially available for additional urban growth after 1995.
Table 13 BASIC PROJECTED PLANNING STATISTICS - 1975-1995 SUB REGIONAL COMMUNITY STATISTICAL AREASITRI- AGENCY WATER SERVICES AREA Population Median Income ($1973) Single Family Housing Units Multiple Housing Units Employment- j obs Vacant Land (acres) Unusable Land (acres) Urban Land Uses (acres) Population 54,620 Median Income (1973) $ 8,669 Single Family Housing Units 13,709 Multiple Housing Units 5,319 Employment-jobs 15,431 Vacant Land (acres) 17,229 Unusable Land (acres) 4,865 Urban Land Uses (acres) 6,536 Population 35,954 39,657 43,435 47,904 51,753 Med'ian In come (1973) $8,984 $9,853 $10,791 $11,065 $119342 Single Family Housing Units 10,658 11,806 12,967 14,342 15,781
Table 13 (Cont ' d) BASIC PROJECTED PLANNING STATISTICS - 1975-1995 SUB REGIONAL COMMUNITY STATISTICAL AREAS~TRI- AGENCY WATER SERVICES AREA 1975 1980 1985 1990 1995 Multiple Housing Units 1,665 2,610 3,565 4,438 5,344 Employment- j obs 7,104 8,832 10,618 12,464 14,402 Vacant Land (acres) 10,964 10,261 9,545 8,737 7,877 Unusable Land (acres) 7,439 7,439 7,439 7,439 7,439 Urban Land Uses (acres)
Table 14 PROJECTED POPULATION GROWTH: 1975-1995 - SUBREGIONAL COMMUNITY STATISTICAL AREASITRI-AGENCY WATER SERVICES AREA BY CENSUS TRACTS - -- - - - -- - TOTAL POPULATIOV BY YEAR % CHANGE COMMUNITY STATISTICAL AREA 19 75 1980 1985 1990 1995 '75 - '95 Census Tract 178.01 3,849 Census Tract 178.02 6,799 Census Tract 179.00 5,232 Census Tract 180.00 2,970 Census Tract 198.00 2,901 Census Tract 200.03 1,375 Census Tract 181.00 Census Tract 182.00 Census Tract 183.00 Census Tract 184.00 Census Tract 185.01 Census Tract 185.02 Census Tract 183.03 Census Tract 185.04 Census Tract 186.01 Census Tract 186.02 Census Tract 186.03 Census Tract 19 3.00
Table 14 (Cont'd) PROJECTED POPULATION GROWTH: 1975-1995 - SUBREGIONAL COMMUNITY STATISTICAL AREAS/TRI-AGENCY WATER SERVICES AREA BY CENSUS TRACTS TOTAL POPULATION BY YEAR COMMUNITY STATISTICAL AREA 19 75 19 80 1985 1990 1995 % CHANGE '75 - '95 Census Tract 192.01 Census Tract 192.02 Census Tract 194.00 Census Tract 195 .OO Census Tract 196.00 -4 I-' Census Tract 197.00 Census Tract 199.00 TOTAL TRI-AGENCY AREA Source: Comprehensive Planning Organization of San Diego Region - PLUM 6/27/74
15,775 acres are considered unusable for future urban development, and assumed to remain in a non-urban status. 8 Employment, both basic and local-serving, is ex- pected to increase from 30,472 in 1975 to 57,609 by 1995. e The employment participation ratio (proportion of working population to total population) is expected to increase from 26.8 in 1975 (a low participation rate which indicates a substantial retirement popu- lation) to 32.0 by 1995. 8 Multiple housing units, indicative of a higher density pattern of residential development, are ex- pected to number 9,313 units in 1975, or represent 23.9 percent of the total housing stock. By 1995, multiple units are expected to increase by 13,848 additional units, and represent nearly one-third of the total housing stock at that time. 9 Population per housing unit is expected to decline from 2.92 personslunit in 1975 to only 2.48 persons/ unit in 1995. e The Carlsbad Community Statistical Area (#43), with a 1995-projected population of 51,596 as compared with 23,126 in 1975, is projected to have a median income in 1995 of $12,573 (in 1973 dollars). This is the highest median income community area. e Carlsbad's population is expected to more than double between 1975 and 1995. 8 Oceanside's population is expected to increase by about 40 percent between 1975 and 1995. 8 Vista's population is expected to increase by about 44 percent between 1975 and 1995. Oceanside is expected to urbanize the largest amount of land -- 5,416 vacant acres -- between 1975 and 1995. 9 Oceanside is projected to contain the most employment by 1995 -- over 25,700 jobs.
e Oceanside is projected to have the most and the highest proportion of multiple family housing units -- 11,143 units by 1995; Carlsbad 6,674 multiple units; and Vista 5,344 multiple units. e The census tracts projected to experience the highest rate of new population growth between 1975 and 1995, in rank order, are: 1 - Tract 200.03 in Carlsbad 2 - Tract 193.00 in Oceanside 3 - Tract 200.02 in San Marcos 4 - Tract 178.02 in Carlsbad 5 - Tract 192.02 in Vista 6 - Tract 199.00 in Vista 7 - Tract 185.04 in Oceanside 8 - Tract 198.00 in Carlsbad 9 - Tract 178.01 in Carlsbad Some census tracts are projected to experience population decline. In summary, it is apparent that dramatic growth and urbanization are being forecast for each community area and the Tri-Agency service area, and that both regional, county, and municipal jurisdiction are planning for accommodating this future growth, both in terms of land use, transportation facilities, and the necessary utility services of water, sewerage, and flood control to meet the demands of the projected and planned new urban development. Comprehensive Plans and Growth Policies For this project, the "controlled trends" growth alternative of CPO, and the San Diego County Interim Growth Policy Statement, Open Space Plan, and County General Plan, along with recently prepared city general plans, provide the basic framework for assessing the growth patterns of the future . The CPO in its Population Growth Policy Study entitled "Environ- mental Impacts of Population Growth in the San Diego Region," June 1974,
noted that over 90 percent of the water used in San Diego County was im- ported by CWA from facilities of the Metropolitan Water District of Southern California, and that the added water supply being provided by the State Water Project would be sufficient to allow the population of Southern California to grow from the current 10 million to 20 million. The 20 million population level for Southern California is expected to be 8 reached between 1990 and 2020. The ontr trolled Trends Regional Development Alternative'' prepared by CPO accepts a 2.4 million 1995 regional population level, but attempts to control the location, density and character of future urban development in order to achieve more balanced and contiguous self-contained urban commu- nities in the region. Planning and growth policies, as well as additional major transporta- tion projects and the support of utility and other public facilities, all ap- pear to be oriented to serving a target population level of 2.4 million, now anticipated to be achieved by the year 1995. The major policy assumptions and conclusions are: 1. The kind of residential development that has been taking place would not be changed, but its locational pattern would be re-directed to prevent "leap-fragging" suburban development and scatteration. 2. Water and sewer facilities would be extended incrementally out from existing served areas only as the actual demand for urban land use occurs. 3. Residential densities would remain low, generally within the ranges recommended in existing community, city and county plans. Overall, region-wide residential densi- ties would increase from a current average of about 6.0 dwelling units per acre to about 7.0 dwelling units per acre.
4. Redevelopment in existing urban areas would be encouraged especially in locations and areas to be served by a re- tional transit system. 5. Nearly 60 percent of new population added between 1975 and 1995 would be accommodated within the existing urba- nized area where a commitment to provide public services has already been made. Population settlement on lands outside existing urbanized areas would require about 50,000 acres to be provided with new local water and sewer facilities. 6. The freeway system would be expanded by the addition of 105 miles of new roads, with a minimum of congestion. 7. A regional transit system, consisting of express buses (86 miles of route) and a "light rail1' (118 miles) sys- tem would serve the surface transportation needs of the region by 1995. (An alternative to the "light rail" sys- tem under study is called the "Advanced Technology Trans- it" -- ATT, which may emerge as the alternate system.) 8. About 800,000 people (one-third of the 1995 forecast population) would live within a 30-minute transit commute of Central or downtown San Diego City. Over 60 percent of the region's population would live within 30 minutes' driving time. 9. Environmentally sensitive lands would not be available for urbanization, and the accommodation of the new popu- lation within existing urbanized areas would significantly reduce the pressure to develop agricultural lands, flood- plains, and other environmentally sensitive open space lands. 10. About 65,200 acres of additional land would be urbanized by 1995, in addition to the currently urbanized area of about 185,700 acres. The CPO "Goals" statement for the region is the basis for regional planning coordination. The goals appear to favor "controlled" or managed quality but limited population growth, with an emphasis upon preserving the environmental quality of the region and enhancing the social, economic and life-style quality of people with minimum disturbance to the natural compatible ecosystem.
The CPO, San Diego County, and the various cities have been examin- ing the issue of growth, evaluating alternatives, evolving policy state- ments on the question of "growth" in order to guide future decisions re- lating to growth inducing plans and projects. The General Plans of San Diego County, the City of Carlsbad, City of Vista, and the City of Oceanside -- as currently available and under consideration for official adoption and revision -- were reviewed in order to gain some insight into each governmental jurisdiction's long- range planning approach and future anticipation of growth and the needed water services, schools, parks, roads, and other urban services. I County of San Diego General Plan A public hearing was held on September 6, 1974 to consider the adop- tion of a revised land-use element map of the San Diego County General Plan 1990. The new composite land-use element map incorporates a11 amend- ments adopted since December 1967 into one map, and changes the title of "Multiple Use Open Space" to "Multiple Rural Uses Area." The Land-Use Element text, which covers territory presently outside incorporated municipalities, is based on projections to 1990 of urban land needs. Consequently, the County Urban Land-Use Plan designates: 22,000 gross acres for industry, about 2-112 times the estimated needs by 1990. 5,500 gross acres are cur- rently (1974) in industrial activity usage. The 1990 projected need is 8,275 gross acres. e 188,000 gross acres for residential and related neigh- borhood parks, shopping centers, schools, fire stations, etc. About 74,000 gross acres are in strictly urban residential use currently (1974). The plan assumes a 1990 County population of 2.3 million. The planned acreage provides a surplus of anticipated needs, and 275,000 acres are already zoned for residential use.
8,900 acres are planned for commercial uses; but 13,400 acres are already zoned for commercial use and only 6,200 acres are actually used, presently, for commercial purposes. e "Rural residential uses," lands at a very low density not requiring new sewer systems and presently not having major installations of urban-type facilities such as curbs, gutters, sidewalks, water and power lines, are designated as "land banks ," and assumed to be needed for future growth of residential, com- mercial, and industrial uses after 1990. An open space or "non-urban" land-use element designates various types of open space lands. The most important category in respect to future growth, development, and water demands is the "Agricultural Sub- Element." The Agricultural Sub-Element states the following: Goals . . . The orderly urbanization of appropriate lands now used for agriculture, to prevent unnecessary elimination of agricultural operations through excessive taxation as- sociated with scattered urban development. . . . The protection of predominantly agricultural areas from scattered and incompatible urban intrusions. The agricultural sub-element text also states ". . . it is recog- nized that urban and agricultural uses often compete for the same lands, and it is expected that when a demonstrated need exists, an orderly con- version from agriculture to urban uses will occur. This generalized plan should not be interpreted to mean that residential development may in no manner locate in areas allocated to agriculture." The San Diego County Planning Department has recently completed a draft report (819174) concerning future water planning goals, policies, and action programs. The significant findings, policy statements,
and action programs described in this draft report which relate to growth and the long-range impact of water supply/quality/service, are as follows: 96 percent of the County's population is served with imported Colorado River and Feather River water (1975- 1977) through the 22 member agencies of the San Diego County Water Authority -- a jurisdiction having no organi- zational relationship to the San Diego County government, Unless effective water reclamation and reuse is insti- tuted, additional sources of imported water will be re- quired to meet projected water demand after the year 2010 or 2020 (according to the CWA). Planning water supply and land use have proceeded inde- pendently even though these activities are closely re- lated. There is a push-pull effect between community growth and the development of water systems. Provision of water to an area facilitates growth; conversely, growth in an area creates a demand for an adequate water supply. The availability of sewers and water is, of course, an in- ducement for property owners and developers to seek zone changes to permit development. In practice, water districts encourage growth (and water sales) by provision of pipe- lines in anticipation of growth. Water and sewerage agencies frequently point out that they could not base their projected need on zoning or general plans which are changed in response to developer requests. Limitations on water and sewer interceptor connections or tie-ins can limit the growth-inducing impact of oversized facilities and utilities designed for agriculture. It is the control over or prohibition of tie-ins and smaller scale systems where the most significant influence over land use and development patterns can be achieved. Individual water districts plan only for the area and services within or potentially within their jurisdictions. The County has no jurisdiction over the installation of lines or facilities. Decisions regarding the location, size and timing of service extensions should be in conformance with adopted
growth management policies; water service ex- pansions required to support existing or future agriculture should have tie-in restrictions which would prevent unplanned urban expansion. The pricing system for providing water services (prices, taxes and other charges) should be structured to promote conservation of water, lessen the load on property taxpayers, and lessen the incentive to urbanize rural land. The actual users of water should pay the cost. Regional estimates of the need for water should be based on environmental quality and desired levels and rates of population and economic growth, rather than standards trend analysis. The County of San Diego has recently adopted, as of August 28, 1974, an "Initial Growth Policy" statement. Of particular significance in rela- tionship to this project are the following "decision guidelines": Urban development shall be ENCOURAGED in areas with adequate public service and utility capacities, or where capital improvements for such services have been planned or installed; in areas with public facility capacity or where such facilities have been budgeted or programmed to support the development proposed. e Urban development shall be DISCOURAGED in areas with- out current adequate public service and utility capacities, without capital improvement plans, or facility capacity has NOT been budgeted or programmed; in areas NOT contiguous to existing urban development; in areas designated for urban use on the County General Plan but NOT located in a Community Planning Area or designated for urban use on a City General Plan. City of Oceanside The City of Oceanside Interim 1974 Land-Use Element of the General Plan designates 14,179 acres for residential use (54 percent of the city's
total area). 5,209 acres are designated for agricultural use; 1,704 acres for commercial use; and the balance of the city's 26,422 acres are classified in open space (3,092 acres) and industrial - (2,238 acres ) No population-holding capacity limits are mentioned by the Land-Use Element. Water and sewerage facilities have been planned to meet pro- jected needs to the year 2000; 75,000 additional housing units are an- ticipated to be built according to Plan guidelines. Oceanside's Interim Land-Use Element is not a final plan, and is not complete since it is not based upon in-depth analysis and research. In addition, the Oceanside Land-Use Element of its General Plan is missing the most important prerequisite to a plan -- a Goals and Policy Statement. Without a Statement of Goals and Objectives, the plan has no means of implementation, its purpose is nebulous, and its role in guiding policy decisions on land-use issues is weak. Policies to achieve land-use goals should be adopted. The Interim Land Use Plan Element recommends that a Citizens Ad- b visory Committee be established to study and recommend goals, objectives and policies suitable for the City of Oceanside. City of Carlsbad As of May 14, 1974, the City of Carlsbad encompassed 23,026 acres or 36 square miles of land. This acreage has been increased dramatically since 1974 by recent annexations. The incorporated area now covers 89.8 percent of the total land area within the Carlsbad Community Subregional Statist- ical Area which contains 25,640 acres. The Revised Final Draft, 9-11-74, General Plan report describes Carls- bad with a "saturation" plan for present boundaries of 256,165 people --
at full development. However, projected population is expected to be less than saturation capacity and is estimated at 194,249. No particu- lar year in the future is anticipated to reach these levels, if ever in the foreseeable future. 13,660 acres are planned for residential use; the maximum dwelling units would be 108,323, and at a population level of 2.6 persons per dwelling unit assumption, population could be 281,640 people. Other planned land uses include 1,048 acres for comqercial; 806 acres for Planned Industrial; 1,156 acres for governmental, schools and utilities: and 6,995 acres for Open Space and Non-Residential Reserves. Projections of actual population for the city of Carlsbad suggest 45,731 persons by 1995, based on CPO forecasts. This is for the incorpo- rated area. For the Carlsbad Sub-regional Community Statistical Area (#43), the CPO's 1995 projected population is 51,596. Presumably, water and sewer services are to be staged and programmed to meet actual growth needs as required and as distributed by market forces within the city of Carlsbad. Certain policy statements contained in the Carlsbad General Plan Land Use Element which relate to the extent, quality and location of future urban growth are as follows: Policies Permit the development of land only after adequate provision for services such as transportation, water, sewerage, utili- ties and public facilities. Arrange land uses so that they preserve community identity and are orderly, functionally efficient, healthful, conven- ient to the public and esthetically pleasing.
Discourage strip commercial development. Locate major commercial and industrial centers in areas which are easily accessible to major transportation facilities. Encourage planned industrial parks as the preferred method of accommodating industrial uses. Develop programs which would correlate rate of growth with service capabilities of the City. City of Vista The City of vista's 1967 General Plan projected a population of 242,000 upon saturation development. This plan has been amended, and no "saturation" population capacity figures provided. The Plan, however, encompasses 25,029 acres of land, and the use, intensity and density of residential development permitted is being re-assessed and determined. Since the Vista General Plan is under revision, and the previous 1967 population holding capacities and land-use designation have been suspended, no data on planned acreages, density or housing units as recommended by the Vista Plan are available. In respect to planning for actual water demand needs, the present Vista General Plan is inadequate for the purpose. Composite Plans and Study Maps A series of maps and overlays were prepared by URS using data and maps supplied by the CPO,. diagrams and charts within the @Controlled Trends" report, Open Space Plan maps prepared by CPO and San Diego County, the existing 1971 land-use map, and maps of existing agricultural land, areas served and to be served with water and sewerage services by 1981, projected new population distribution, the County 1990 General Plan, and plans of Oceanside, Carlsbad and Vista. A composite land-use plan was evolved from this process.
urns The purpose in preparing these study maps was to provide a visual tool to further analyze planning processes for future growth. Visual analysis, using the overlay system on top of the composite Land-Use Plan map for the Tri-Agency Area and Statistical Community Sub- regions resulted in the following conclusions: More land is planned for residential and other urban uses than is projected to be urbanized by 1995, or needed by the forecast growth. e More land is planned for residential and other urban uses than,is currently or planned by 1981 to be served with water. Much land currently served with water is agricultural, and could be urbanized if land-use poli- cies or "controlled growth" techniques are inadequate. More land is planned for residential and other urban uses than is currently served or planned to be served by 1981 by sewerage services. Some close-in agricultural land, mostly within present municipal boundaries, is planned for future residential development. This is particularly important in Carlsbad and Oceanside. Future Water Supply Predictions Rough projections can be made to illustrate the demands that will be placed on water supply agencies in accommodating the planned development of the Tri-Agencies service area. In making these projections the following assumptions have been made: CPO population projections (PLUM model) have been used. An average per capita water consumption rate of 0.36 acre-feet is used. (This is an average of estimates for each of the agencies for the year 1972-1973 as listed in the CWA annual report for that year.)
0 A peaking factor of 2.1 is used. (This factor represents an average for the ,three agencies as determined by Montgomery Engineers, SDCWA Filtered Water Distribution Study, 1974.) Based on these criteria the following predictions were made: CPO Population 114,000 130,000 145,000 164,000 180,000 Est. peak demand (cfs) 119 136 151 171 188 The capacity of the existing distribution system is 103.2 cfs. With the addition of the proposed project the capacity of the combined system will be increased to about 175 cfs. The projections made do not consider the storage capacity already built into the system. This storage capacity will have the effect of reducing peak flow demand. Nonetheless, the storage capacity is limited and the projections made illustrate the exist- ing system overdemand. In the future, it appears that the proposed project should satisfy the planned growth water demands until the 1990-1995 period. As such, the sizing of this project easily meets the objectives of provid- ing water for relatively constrained growth objectives as outlined by CPO .
0 A peaking factor of 2.1 is used. (This factor represents an average for the three agencies as determined by Montgomery Engineers, SDCWA Filtered Water Distribution Study, 1974.) Based on these criteria the following predictions were made: CPO Population 114,000 130,000 145,000 164,000 180,000 Es t. peak demand (cfs) 119 136 151 171 188 The capacity of the existing distribution system is 103.2 cfs. With the addition of the proposed project the capacity of the combined system will be increased to about 175 cfs. The projections made do not consider the storage capacity already built into the system. This storage capacity will have the effect of reducing peak flow demand. Nonetheless, the storage capacity is limited and the projections made illustrate the exist- ing system overdemand. In the future, it appears that the proposed project should satisfy the planned growth water demands until the 1990-1995 period. As such, the sizing of this project easily meets the objectives of provid- ing water for relatively constrained growth objectives as outlined by CPO .
ENVIRONMENTAL IMPACTS OF THE PROPOSED PROJECT
Section VI ENVIRONMENTAL IMPACTS OF THE PROPOSED PROJECT A variety of identified or potential environmental impacts have been identified. Most consist primarily of short-term construction-related im- pacts which can generally be effectively mitigated. The following section discusses these and other direct and indirect impacts. TOPOGRAPHIC MODIFICATION To the degree possible, project site topography will be returned to the natural grade. Excess material from the excavations will be spread evenly over construction sites. Although grading and leveling will be required at sites of surface facilities, such areas affected will be small and the overall topographic impact minimal. GEOTECHNICAL IMPACTS A general feeling of the nature of possible geologic and geotechnical problems associated with the implementation of the proposed project may be obtained from a review of the Urban Geology Master Plan for California pro- duced by the California Division of Mines and Geology in 1971. In this study identified or potential geologic problems have been summarized on a quadrangle (7-1/2') by quadrangle basis. Those summaries covering western San Diego County are presented graphically in Figure 12. Positions within each quadrangle correspond to geologic problems as identified in the legend. Each problem iden- tified is rated on an increasing scale of 1 to 3. The significance of ratings for each problem is described in Table 15. The approximate location of the pro j ect is indicated.
2 1 2 123123 2 2 1 22 2 2 23 12 3 21 2 1 Letter position within each quadrangle 11 12 1 2 refers to geologic ~robiem &severity 123 1 2 2 122 122 ratingbeioW GEOLOGIC PROBLEM A - Earthquake Shaking 0 - Flooding C - Volcanic Eruption D - Tsunami E - Fault Displacement PACIFIC OCEAN F - Landslide PROJECT ----"" G " Subsidence QUADRANGLE H - Erosion Activity I - Expansive Soil J- Lossof Mineral ' Resources Severify Ratings 1 High or Possible Source: California Division of 2 Moderde Mines & Geology, 3 Low Urban Geology Master Norre - or Plan for California, not rated December 1971. 3
Table 15 GEOLOGIC PROBLEMS AND SEVERITY RATINGS ES Earthquake Shaking 3 High (Zone 111) 2 Moderate (Zone 11) 1 Low (Zone I) FL Flooding 3 . Possible (has had historic flood) - Not Possible VI Volcanic Eruption ' 3 High (historic eruption) 2 Moderate (Holocene deposits) 1 Low (Plio-Pleistocene deposits) - None TS Tsunami FD Fault Displacement LA Landslide 3 2 1 SU Subsidence High (historic loss) Moderate (high loss potential if conditions unfavorable) Low (public beach areas, life loss potential if warning ignored) None (coastal cliff area or inland) High (historic movement) Moderate (cuts Quaternary) Low (others)~ None High Moderate Low High (occurring today) Low (possible) None
urns Table 15 GEOLOGIC PROBLEMS AM) SEVERITY RATINGS ( continued) EA Erosion Activity 3 High 2 Moderate 1 Low EX Expansive Soil 3 High 2 Moderate 1 Low LM Loss of Mineral Resources 3 Possible (resources present) - Not possible (resources absent)
nearest vity Figure 13, RANGES OF MAXIMUM ACCELERATIONS IN ROCK
Using this summary, a general description of potential problems can be made. The project site is subject to moderate earthquake shaking and possible flooding. Considering the nature of the project, however, flood- ing is not seen as a major problem except perhaps during the construction phase in stream crossings and canyons. Tsunami hazard is eliminated by elevation and distance inland. No significant fault displacement hazard has been identified. Land- slide potential is rated as low. Subsidence problems are not anticipated. Variable erosion activity may occur. A high occurrence of expansive soils may be expected. Loss of natural resources is considered negligible. The following discussion covers geologic and geotechnical impacts and hazards considered to be of possible concern based on this inventory and site visits. These categories are not of necessity expected to result in significant impacts or induce hazards. On the contrary, very little in the way of such impacts is expected assuming application of standard engineer- ing practice. These subjects are elaborated on mainly to insure inclusion of their consideration in project implementation. Earthquake Shaking Since Southern California is noted for its active seismicity, it is reasonable to assume that structures may be subject to the shaking effects induced by earthquake activity. While no active faults and little epi- center activity have been identified at or near the project site, it is nonetheless susceptible to effects from more distant events. Figure 13 presents a compilation of ground accelerations in rock versus earthquake size and distance for western North America. These accelerations approximate the forces structures can be expected to be subject to during earthquakes.
Shrink-Swell Behavior Many clay soils swell when wetted and shrink when dried out. Dry- ing and shrinking of clays having this property often cause cracks to appear in the soil. The movement of soils caused by shrinking and swell- ing can cause damage to building foundations and water tanks. Relative distribution of soil types exhibiting shrink-swell potential is shown in Figure 14. Primary concern lies with the engineering of surface struc- tures rather than with the transmission lines themselves. Erosion Potential Disruption of the ground surface and removal of vegetation during construction will increase the project site's susceptibility to erosion. Many of the soil types present have been identified as being subject to erosion. In Figure 15, soil units subject to moderate or severe erosion potential have been indicated. Erosion potential is more severe in regions of high slope and during rainy or windy periods. Note that practically all of the pipeline alignment lies in areas of severe erosion susceptibility. Estimates of the degree of erosion acceleration due to construction over the natural rates range from 10 to 10,000 times. This range undoubt- edly includes extreme circumstances. Perhaps more applicable to the site is the estimated range of Wolman (1964) of 10 to 100 times. Using this range possible sediment generation of up to 9,950 cubic meters above the natural rate could be expected where no erosion control measures are ap- plied following construction. Application of erosion control technology including mulching and reseeding and seasonal timing will greatly reduce this erosion potential, although not completely eliminate it. The impact of accelerated erosion will be felt primarily in short sections of the tributaries to Aqua Hedionda Creek near the project site.
Indicated on this figure is the approximate distance to the nearest area of abundant epicenter activity some 35 miles away to the north (see Figure 7). As interpreted, ground accelerations from activity in this area are not particularly high (less than 0.2 G). The project does lie considerably closer to other well-defined faults such as the trace of the Elsinore fault. No or little historical activity is associated with the nearest portion of the Elsinore fault, however. Whether this "histor- ical inactivity" insures that that section of the fault will remain in- active cannot, unfortunately, be assumed. Given proper consideration to the effects of groundshaking, proper pipeline design should eliminate hazards due to this effect. Landslides The project site has not been classified as being in an area par- ticularly susceptible to soil instability. Relief is generally low and selection of the pipeline route avoided areas requiring extensive cut- ting. Soil Liquefactlon Liquefaction is a phenomenon typically occurring in saturated sandy soils in response to ground vibrations. If the vibration (as in response to an earthquake) is strong enough and of sufficient duration, the load of the overburden soil and structures, if any, is transferred from the soil grains to the interstitial water, drastically reducing bearing ca- pacity. Improperly designed structures may sink or tilt in response to liquefaction. While not considered to constitute a major hazard, soil characteristics at project site, particularly at stream crossings or installations, should be given consideration in the engineering design.
While it is possible that construction may be phased to miss the short rainy season, soil and vegetation are slow to recover and will eventually be subject to rainfall and erosion. Scars of existing con- struction are locally visible after recovery periods of up to 14 years in many areas, and attempts at soil stabilization through cultivation and seeding have met with varying degrees of success, Figure 16 indicates limitations restricting the conversion from brush to grass. As shown, approximately one-third of the route contains soil types restrictive to the establishment of grasses. Extreme care must be applied, however, to prevent possible intro- duction of turbidity into local low flow streams, which are easily over- loaded, and water supply reservoirs. Adequate technology exists for re- tarding soil erosion and it is anticipated that these will be utilized where necessary as standard procedure. Recommendations are supplied in the section on mitigation measures. Loss of Mineral Resources Some of the earth materials encountered along the pipeline route have been or have the potential of utilization as construction materials. These consist almost exclusively of surficial deposits of sand and gravel, and some decomposed granite. The locations of areas having soils potenti- ally suitable for construction material are shown in Figure 17. Other than at one locality these potential resources have not been developed historically. While local reserves of this type of material are currently abundant, they are nonetheless essentially finite. An undefined quantity of natural resources will be consumed in the implementation of the project. These include construction materials and fuel requirements that are not by themselves considered significant.
CALAVERA I LAKE Y 0 2000 4000 w - 1-1 LOW Approxi mate Scale ( feet) / MODERATE SEVERE Figure 16. LIMITATIONS FOR CONVERSION FROM BRUSH TO GRASS / SECOND SAN DlEGO AQUEDUCT
' AIR QUALITY IMPACTS Construction-Related Impacts Construction-related air quality degradation resulting chiefly from the pipeline-laying operations involved in the proposed project could impact small areas close to the actual activity. These impacts can be divided into two major groups: (1) exhaust emissions from the construction equipment and (2) particulate emissions arising from soil disruption and wind erosion on the construction sites. Because of both the present ambient conditions and amount of area likely to be disturbed during construction, it is most likely that particulate levels will have the larger impact. Exhaust emissions (consisting of CO, HC, SO2, NOx, and particulates) can be quantified using currently acceptable EPA emissions factors if certain local influencing parameters are known. The parameters include wind speed, atmospheric stability, and type of equipment utilized. At- mospheric factors (such as wind speed) can be estimated based on meteoro- logical records for the San Diego area. However, equipment types are not concisely known. At best, one can only assume that the types and numbers of equipment utilized in previous pipeline-laying operations will roughly continue to be the same. Particulates resulting from soil disruption and the subsequent wind erosion of exposed surfaces, however, are not so easily quantified. The amount of particulates arising from this source depends both on the above- mentioned parameters and on the amount of area disturbed and that area's soil type. Moreover, relatively few studies have been carried out with regard to fugitive dust emissions upon which estimations might be based if the above factors were known. Thus, it is only possible in this anal- ysis to attain a general idea of the air quality impacts involved in con- struction, particularly in respect to particulate levels.
Based on what information is available for the project area (with regard to influencing parameters) and earlier fugitive dust'studies for similar construction activities (URS, 1973), the following anticipated pollution potentials (both particulate and gaseous) for the project were estimated. These estimates are shown in Table 16. Likewise, Tables 17 and 18 show the approximate ranges of on-site and downwind pollutant con- centrations that may be expected for each category (i.e., each level of pollution potential) . Using these possible pollutant ranges and the present ambient air conditions, it was also possible to predict the probable percentage of time when ambient air standards might be exceeded if the construction was taking place now (see Table 19). As can be readily seen, the occurrence probabilities for the various standards to be exceeded vary widely. Clearly, however, the largest prob- lem would concern particulate levels near the construction sites. The current standard for particulates is already exceeded 55 percent of the time in the project area (based on values from the El Cajon monitoring station). The only other problem pollutant, oxidants, is exceeded 26 per- cent of the time and is probably less affected due to the relatively low levels of exhaust emissions likely to result from the project construc- tion. Thus, while there are no particulate values which might cause health hazards, the large amounts of particulates likely to be generated by this construction activity should cause nuisance conditions and short- term standard violations as far as one mile downwind from the open ter- rain pipe-laying operations. Such a result would have to be considered as a small, but probable, adverse impact. Secondary or Indirect Impacts This project involves increases in quantity of water, and will allow the availability of higher quality water in an area not currently re- ceiving it.
Table 16 CONSTRUCTION AIR POLLUTION POTENTIAL LENGTH OF APPROX. ACRES AIR IMPACT AIR IMPACT IMPROVEMENT EXPOSED DURING PARTICULATE GASES TYPE OF IMPROVEMENT (thousands of feet ) CONSTRUCTIONa CATEGORY~ CATEGORY~ Open terrain construction 3 6 11 6 D D Under street construction P o a - Includes all area within the District right-of-way plus any necessary temporary 0 easement. (%1401 for open terrain ) (% 60' for construction under streets) b - See Tables 17 and 18 for approximate values to be expected on-site and downwind from projects . A - Least air pollution potential D - Greatest air pollution potential
Table 17 RANGE OF PARTICULATE VALUES WHICH MAY OCCUR FOR PIPELINE PROJECTS (llg/m3> PART1 CULATE 1/4-MILE 1--MILE IMPACTa ON-SITE DOWLWIND DOWNWIND CATEGORY NUISANCE^ SUSPENDEDC SUSPENDED SUSPENDED B and C 1000-10,000 160-7000 3-300 <1-30 a. See Table 15 b. Particulates >I00 u in size. c. Particulates 0.1 to 100 p in size.
This will facilitate changes in land-use mix. Possible secondary and in- direct impact on the air quality of the San Diego Basin must therefore be considered. The CPO has conducted an evaluation of potential air qual- ity degradation vs. population expansion (June 1974). Their approach was -- ... to view the future air pollution situation [by determining] the air quality carrying capacity for the region. [They] assumed that the EPA standard for oxidant is absolute and cannot be exceed- ed. By dividing projected per capita emissions for each year into the total EPA figure for allowable emissions (a constant 51.9 tons per day through the entire projection period) a theoretical estimate of how many people the region may contain and not exceed the fed- eral air quality standard [was] derived. Figure [18] shows region- al population projections and air quality carrying capacity esti- mates using pessimistic, moderate, and optimistic assumptions about the implementation of technological advances in air pollu- tion control. Future per capita air pollutant emissions were derived from work undertaken by the San Diego County Office of Environmental Manage- ment (OEM). OEM has made projections of the technological advances in emission control which are expected to be implemented for 6 major categories of pollution sources to the year 2000. The projections consider only the implementation of technological advances in pol- lution control; they do not assume any changes in human activity, such as reduction in vehicle miles travelled. In addition, OEM calculated alternative projected emission levels for two categories, light duty motor vehicles (automobiles) and other (petroleum handling and storage, solvents, etc.), based on pessimistic and optimistic assumptions about emission control for these sources. The figures for automobile emis- sions provided by OEM [were] increased by CPO to reflect the anticipated increase in per capita vehicle miles travelled. [This evaluation] pro- jects that 10% of all trips will be made on mass transit. If the pro- jected use of transit were to increase, per capita vehicle miles tra- velled and automobile emissions would decrease. Figure [18] illustrates that the population carrying capacity of the San Diego region, using air pollution as a single criterie8,varies according to the degree to which technological emission control tech- niques are implemented. The current population of the region exceeds the air quality carrying capacity because of the existing high per. capita emission rates. The year in which the region can expect to achieve Federal air quality standards depends both on the degree of
Population (mi'llions) 1985 Year
implementation of technological advances in emission control and the growth of regional population. Table [20] shows the alterna- tive years in which Federal air quality standards will be met based on the two factors, technology and population growth. Cur- rent trends in population projection and the pessimistic and mod- erate assumptions about technological implementation, indicate that the standards won't be met at all. Of course, it is possible to meet Federal air quality standards earlier by policies such as reducing per capita vehicle miles travelled. It can be con- cluded that the lower the region's population growth rate the earlier the air quality standards will be met. Continued rapid population growth will increase the need for implementation of advanced emission control devices and/or major changes in the life style of the region's residents. HYDROLOGY/WATER RESOURCES Construction Impacts The proposed project will increase the erosion potential of land peripheral to construction activities. Exposed soil is vulnerable to erosion by stormwater runoff. Project-induced erosion may lead to substantial siltation of downstream receiving waters. The potential for erosion and subsequent siltation of downstream receiving waters is also discussed within the geology section of this report. Siltation of downstream receiving waters due to project-induced ero- sion could (1) impair beneficial uses of receiving waters, (2) adversely affect aquatic life, and (3) modify the physical characteristics of receiv- ing waters such as channel dimensions, etc. It is believed that the impact of siltation can be effectively mitigated. Long-Term (Normal Activities) Impacts Surface Waters It is anticipated that there will be no significant impacts upon fresh surface waters which derive their water from local runoff due directly
Table 20 DATE FEDERAL AIR QUALITY STANDARDS WILL BE MET GIVEN ALTERNATIVE POPULATION AND TECHNOLOGICAL ASSUMPTIONS... REGIONAL POPULATION PROJECTION ZERO SLOW CURRENT ASSUMPTIONS MI GUT ION GROWTH TRENDS Pessimistic 199 1 -- -- Moderate Optimistic
to the project. However, indirect impacts on surface waters may occur in response to the growth of the area facilitated by the availability of water. Surface runoff associated with urban development characteristi- cally contains a variety of contaminants. Life occurring in intermittent streams and particularly in the lagoonal areas is extremely sensitive to such contamination. Impacts on these biological communities via contami- nated runoff can, however, be virtually eliminated through proper storm- water collection and treatment facilities. BIOLOGICAL IMPACTS A number of direct and indirect impacts will occur with the implemen- tation of the proposed project. These impacts include the physical dis- turbance and removal of various populations during construction, and the long-term indirect effects of the land-use conversion facilitated by the increased availability of water. Direct impact on vegetation and wildlife will be associated with con- struction of the pipeline. Construction activities will demand brush re- moval along the easement to accommodate construction vehicle access, trench- ing debris, and vehicle storage. A swath 45 feet wide (6 miles long) would require approximately 30 acres of brush removal. An additional 10 foot section on each side of the cleared area would be subject to stress from construction equipment operation and dust generation. Accidentally caused fire by a machinery-induced spark or a careless cigarette could virtually destroy the grassland habitat of the entire local area. The major impact upon the property of Rancho Agua Hedionda will be noise due to workmen and construction equipment. The raptors utilizing the area for feeding and nesting may be disturbed to the point of leaving established nests.
Operation of the completed pipeline will entail periodic pipeline in- spection, and road and stream crossing maintenance. Compaction of the service road soils will retard brush growth along the length of the pipe- line. Inspection vehicles will contribute air pollutants, disruptive noise, and dust to the surroundings, although other than dust, it is doubt- ful that these impacts would be measurable. Indirect impacts will result through the increased water supply to the Trl-Agency area. The availability of water will allow the realiza- tion of existing land use planning. Current land use plans call for the development of much of the service area as low residential developments. Such land use conversion can be expected to result in an increase of im- pervious surface, increased runoff, and a decrease of biotic resources. As the lands serviced by the proposed project are developed, the quality of the area's runoff will change, reflecting the land use. Generally speaking, the changes can be expected to be of a degraded nature. Urban runoff contains higher than natural levels of various pollutants such as nutrients, metals, pesticides and herbicides, oil and grease, bio-stimulants, and oxygen-demanding materials. Ultimately runoff from the area will enter the lagoons of %ua Hedionda and Buena Vista Creeks. These important wildlife sanctuaries are already heavily stressed by the activities of man. Uncontrolled drain- age from the project area could further degrade these areas. The long expected residence times of the foreign chemicals may direct- ly affect the bird population health or indirectly affect the community by poisoning the food sources.
NOISE IMPACT OF PROJECT Short-Term Impact Noise levels from construction activities are normally annoying to residential areas because their residents do not adapt well to varying noise environments. Trench digging and grading, the major continuous noise source, typi- cally generates average noise levels of 83 to 89 dBA measured 50 feet from the site, with peak noise levels of 95 to 100 dBA. Although periodically high, little overall noise impact is expected from these operations. The reasons are: Most of the pipeline goes through districts with low sound sensitivity. Distance attenuation of the noise will be good and will decrease much of the impact on the scattered houses in the area. e The speed of most pipeline operations is fairly rapid (normally around 300 feet per day). Therefore, few complaints are expected from local residents. ARCHAEOLOGY - IMPACTS Surveyed archaeologic resources of the pineline corridor will be im- pacted directly during the construction period. As the surrounding area is indicated to be rich in archaeological resources, additional and per- haps even greater impacts will arise from construction associated with the development of the future service area of the proposed pipeline.
Four of the five sites reported during this study will be directly affected by construction of the proposed pipeline. Although pipeline diameters vary along the main and secondary lines, most trenches will probably be excavated by backhoe. Trench widths of 24 to 36 inches may be cut through the sites 2 through 5 as listed in the appended survey re- port. Fragile remains (possibly including skeletal elements) would be de- stroyed immediately either coming out or during back filling. All remains would be disturbed considerably, although their relative position may not be radically dislocated (maybe up to 6 to 8 feet). During construction, personnel and general public will frequent the corridor more than they do at present. Exposure of the surveyed sites in , this public disclosure document will focus the attention of some who may attempt to remove remains from the site before or during the excavation of the trenches. Such vandalism by the public or construction personnel would constitute a significant adverse impact. Selective removal of the more attractive remains from the corridor may be as significant as their dis- turbance during excavations. Archaeologic remains without specific record of their occurrence and association quickly lose scientific value. Once excavation activity diminishes, (i.e., during operation) the gen- eral public will probably have minimally controlled access. Again, the public awareness of the sites in or near the corridor will encourage uncon- trolled exploration of and removal from these sites and others which are probably located in the vicinity. Adverse impacts from this awareness and access can be attributed to the project. Since new agricultural and urban/suburban land conversion will undoubt- edly follow the proposed pipeline, implementation of the pipeline operation will secondarily and in part result in the potential disturbance and removal of archaeologic remains.
Grading for tract houses, subsidiary pipelines, other underground utilities, and even small road excavations can destroy one or more archaeologic sites. Many mitigation measures can be implemented to reduce, eliminate, or even generate beneficial results from the final implementation of the proj- ect and mitigation measures. AESTHETIC IMPACTS Considerable earthmoving will be required along the pipeline route, re- quiring the total removal of top soil and vegetation. Therefore, the activi- ties will temporarily impact the visual impression to the general public along the alignment. This aesthetic distortion will be increased by the move- ment of large, highly visible bulldozers, ditch diggers, and other equipment. The visual impact associated with construction will be most noticeable around the connection to the Second Aqueduct and near the crossing of El Camino Real. The remaining portion of the site will have associated a lower aesthetic impact because of low usage by people. - Long-Term Impacts After construction activities have ceased, many of the initial, visually disturbing aspects of the project will be gone. Recovery time of the pipeline scar will vary and will range from rapid complete recovery in the more fertile areas to many tens of years in some other areas. After recovery of the area, the only visual indications of the project will be the access road and a few small surface structures (vents, etc.). Should uncontrolled access to the public be allowed, the disruptive effects of offroad vehicle activity can be expected to prolong or increase the visual impact of the project.
SOCIOECONOMIC IMPACTS Indirect Long-Term Impacts The proposed pipeline will provide additional quantities of improved quality water and necessary linking distribution facilities to deliver the improved quality water to the three member agencies. Based upon CWA fore- casts and water consumption factors the project will deliver enough water to supply the forecast population expected to reside in the Tri-Agency terri- tory at least to the 1980-1985 time period. Improved water quality, for human drinking needs as well as for other uses, including agriculture, will be beneficial to the residents of the Tri-Agency area and the cities of Oceanside, Carlsbad, and Vista. Better quality water will be beneficial to irrigated plant life, and for recycling purposes, or recharging underground supplies. With proper regionwide water management policies and programs, the improved qual- ity of imported water can be beneficial to the long-term environment of the region. An adverse indirect long-term impact is the fact that improved water quality availability as well as additional water service capacity will facilitate the forecast urbanization as presently projected and being planned for by the Comprehensive Planning Organization, San Diego County, and the cities of Oceanside, Carlsbad, and Vista. People and the associated busi- ness/industrial activities must have water, as well as sewerage services and other utilities. Land development into urban uses, however, cannot occur with the availability of water alone; such development must (under land use de- velopment standards and requirements for a building permit) also have accessibility -- through streets, roads and highways; must also have sewerage services/facilities; and must have electricity service. Land
development into urban uses must also have zoning and subdivision approval as administered by local planning commissions before any building permits for new construction are authorized. Indirectly, water quality and availability are necessary for new urban development to occur, but such quality and availability do not cause' urbanization, population growth, or economic expansion. Water service and healthful quality domestic water are necessary, however, along with sewerage, flood control, electric power, and transportation accessibility for any standard quality urban-type human settlement pattern. A beneficial long-term and indirect impact of improved water quality may be the enhancement of the productivity of agricultural lands under irrigation in this part of San Diego County. Lower salinity Feather River water and filtered Colorado River water will result in lower salinity agricultural return flow and lower salt build-up in soils. Salinity, of course, is an increasing problem to the agricultural productivity of Imperial Valley, which is dependent upon imported Colorado River water. Although the improved quality water will cost more than present water for agricultural purposes, the quality characteristics will help offset the cost increment through the maintenance of long-term soil productivity characteristics. Another factor bearing upon agricultural use of water is the new "drip" method of irrigation, which uses substantially less water and is more plant-effective than previous techniques. This technique also is more efficient since evaporative losses of water are greatly reduced. A problem with the "dripw irrigation technique has been the clogging of nozzles due to the poor quality of Colorado River water -- particular- ly the high mineral content and salinity factors. The elimination of such defects in the water through this project will tend to make the "drip"
irrigation technique work better and continuously, and save farmers time, effort and problems associated with this irrigation technique. Thc. project will have no effect upon present operating policies con- cerning the public use of lakes and reservoirs for recreational purposes. P If history repeats itself, the construction of inspection/access roads will facilitate the increased recreational use of the area by offroad ve- hicles. Uncontrolled use of the area in this fashion can be expected to aggravate a variety of the anticipated minimal impacts to the point where they will probably become significant. The construction phases of the project can be expected to make some demands on public utilities and services including water supply, police (security and traffic control), gas and electric services, and communica- tion utilities. The magnitude of these demands has not been assessed in detail, but they are anticipated to be minimal. On the long term the project will facilitate development of the surrounding service area. The resultant urbanization will place increased demands on local utilities and services. Accommodation of these require- ments should fall under the long-range planning responsibilities of each respective municipality.
Section VII UNAVOIDABLE ADVERSE IMPACTS WHICH CANNOT BE AVOIDED SHOULD THE PROJECT BE IMPLEMENTED A variety of direct and indirect impacts may be associated with im- plementation of the proposed project whicb may be considered adverse. Generally, these adverse impacts are anticipated to be of relatively low significance, and most can be effectively mitigated. a Likely increases will occur in the annual erosion production of the site, access and staging areas during the construc- tion and recovery periods. Increases will be in the form of both construction related dust and rainfall erosion. Elevations in current levels will occur, but can effective- ly be held to very low levels through application of erosion control technology. (Such mitigation is included in all San Diego Water Agency projects.) a A certain amount of natural resources will be utilized by the project. These include concrete and steel used in pipe construction, local sand and gravel for bedding material, petroleum products and miscellaneous other minor resources. When compared to overall environmental impacts and need for the project, this commitment of re- sources is justified . a A limited amount of vegetation will be removed or damaged. Effects on wildlife will consist mainly of disturbance during construction and removal of habitat. Many portions of the local region have demonstrated fairly rapid recovery following construction activities, and it is believed that the project site will eventually recover. Few surface structures are included in the project limiting interference with this recovery. Periodic disturbance will be associated with routine pipeline inspections, although the impact of this activity is anticipated to be minor. a The possibility that several air quality standards will be exceeded during construction exists. Of primary concern is the generation of elevated particulate loadings. Considering the brevity of the construction period, the use of dust control technology, and the general remoteness of the area, this possible impact is probably of small significance.
a Traffic disruptions will be associated with the urbanized portions of the alignment during construction. As no street closing will be involved, this impact will probably have nuisance value only. a Construction noise will additionally impact the urbanized areas for the short construction periods associated with these small segments of the alignment. Further reducing the significance of this impact is the fact that con- struction will be restricted to normal working hours. a Several identified archaeological sites will be destroyed or disrupted. Provision will be made for the orderly salvage of these sites by qualified individuals prior to or during construction. a The overall aesthetic quality of the area will be disrupt- ed during the construction-recovery period. On the long term, an access road will be maintained. The viewshed of the alignment is, however, limited and construction areas should recover fairly rapidly. a Implementation of the project wil impose minor demands on local public utilities and services. These include power demands, communications, traffic control, and street maintenance services. Several indirect adverse impacts can additionally be associated with the project. Most of these involve the future development of the surround- ing area. If well controlled by each municipality this growth can be beneficial. If growth facilitated by the availability of water is not controlled it can be adverse. In any event, a variety of indirect im- pacts are possible, including the following: a Additional commitments of resources and the possible exclusion of existing natural resources from potential exploitation. a Local increases to air pollution, sewage and solid waste generation, and so on, related to the increased use of the area. a Additional stress on local biological systems, particular- ly in the coastal lagoon areas.
e Destruction of possible archaeological sites found or believed to exist in the immediate area (regardless of future development of the area, the construction of additional access to the area will place such sites in jeopardy) . Increased traffic related to the predicted growth.
MITIGATING MEASURES
Section VIII MITIGATING MEASURES A number of techniques will be applied and are recommended for implementation to reduce construction impacts and facilitate recovery of the project areas. Recommended measures are designed to be incor- porated effectively into standard post-construction (clean-up - restora- tion) operations. EROSION CONTROL As standard operating practice erosion control measures are included in the project. Generally speaking, these measures have included some drainage control and revegetation attempts. Revegetation has met with marginal success partly due to the local environmental conditions , but also due to the techniques used and the continued redisturbance of the area. While it is recommended that these procedures be continued it is suggested that the following operations also be considered. 6 Soil profiles in the area are extremely thin and generally mixed with underlying rock during pipelaying operations. As this soil is critical in the reestab- lishment of vegetation, it is recommended that top soil be segregated and stockpiled for return to its original position. d A certain degree of surface texturing of disrupted areas is recommended. These actions accomplish a number of goals and are particularly important in areas of higher slope. They will accomplish the following : reduction of soil erosion through reduction of the erosive energy of overland flow of runoff; trapping of eroded soil and retention of water, facilitating regrowth of plants ; and finally, reduction of the desirability of motorcycle use of rights-of-way (a significant factor in the existing slow recovery of many areas) .
The erosion control techniques could include diversion ditches and terracing. Micro-terracing or the cutting of "cow trails" along con- tours has proven very effective in erosion control and should be explored for economic feasibility in this case. After surface texturing, revegeta- tion should be conducted. Revegetation through the technique of cultivating and feeding has been employed as a standard procedure. Use of perennials such as Bermuda grass or natural annuals and perennials, barley and rye grass is recommended. Finally, equipment operation outside of construc- tion zones should be kept to a minimum. DUST Standard dust control techniques will be employed to reduce particu- late generation. . NOISE The short-term environmental noise impact to residential communi- ties can be reduced by: e Installation and maintenance of effective mufflers on all construction equipment powered by internal combustion engines. 0 Keeping the activities of noise sources (earthmovers, dump trucks, etc.) within the area to a minimum. Reduce truck traffic in residential areas to a minimum. e Reduce or synchronize as much of the blasting as possible. BIOLOGY REVEGETATION Revegetation (cultivation and seeding) of disturbed areas will be con- ducted to promote rapid recovery and provide erosion control. Top soils should be kept separate from subsoils and replaced as topsoils. Where 122
practica1,excess highly fertile soils should be spread in adjacent areas having poorer soil quality. It should be noted that unless access to the area is controlled, the activity of offroad vehicles will essentially make revegetation efforts useless. ARCHAEOLOGY Cooperation between San Diego County water agencies and appropriate archaeological concerns is routinely practiced. These agencies are noti- fied of proposed construction and are allowed time and access for ob- servations, documentation, and salvage operations. A broad spectrum of measures lies between the two basic measures which can be undertaken to insure the lowest or eliminate impacts upon archaeologic remains. These measures range from scientifically con- trolled excavation of the impacted areas to relocation of the proposed project. In areas where known surface remains may entice uncontrolled removal, such remains should be collected by the qualified archaeologist for preser- vation in a recognized institution. If the site may be subject to van- dalism or uncontrolled excavation, a layer of clean fill (at least a foot deep) may be placed over the surface of the site with a suitable marker layer, adequate location information, and photos of the site by the quali- fied archaeologist. Numerous methods can be employed to restrict public access before and after construction, Construction personnel should be instructed not to remove archaeologic remains from the corridor and should notify an archaeologist whenever encountering any remains. It is recommended that an additional survey of the entire service area of the Tri-Agencies' pipeline by the appropriate agency(s) be conducted prior to the planned area development. 123
Such a survey could reduce potential future adverse impacts by permitting relocation of projects or reduction of disturbance during excavation. These surveys and appropriate controlled excavation of re- mains could provide very valuable information regarding the patterns and composition of prehistoric society in northwestern San Diego County. SOCIOECONOMICS It is recommended that land-use plans for the future development of those areas not already treated be adopted as soon as possible. Ideally, such plans will provide for the most beneficial utilization of the areas in question. These plahs should include provision for the protection of the natural environment and practical preservation of open space. Of particular concern is planning for the preservation of Aqua Hedionda and Buena Vista lagoons.
ALTERNATIVES TO THE PROPOSED PROJECT
Section IX ALTERNATIVES TO THE PROPOSED PROJECT A variety of alternate methods of meeting the existing and projected water supply demands of the study area have been investigated by the agencies involved and their consultants. The proposed project was selected as presenting the most acceptable overall alternative, considering environ- mental, economic and engineering criteria. For the purpose of this dis- cussion, alternatives to the proposed project may be grouped in the follow- ing categories: w No project. As required by the California Environmental Quality Act guidelines, a dis- cussion of the "no project " alternative is included. w Construction of three separate pipelines, each servicing an individual agency. w A variety of alternate alignment routes. NO PROJECT Under this alternative, no Tri-Agency pipeline would be constructed. Given the existing water supply, water shortages during peak flow periods could be expected as soon as the next dry season. These possible short- ages could involve stoppage of flow and water rationing. Most impacted would be those agricultural and domestic consumers at the extremes of the existing system. The proposed pipeline is designed to backfeed the existing distribu- tion systems, and will have the effect of prolonging their useful life. Without the project, these systems will require extensive modifications to maintain their adequacy, with associated costs and disruptions.
In the event of "no project'' it is likely that the old transmission systems would be modified to overcome the existing deficiencies. Accord- ing to standard practice, they will be sized to accommodate the planned growth in each area. In other words, it is felt that growth in the cur- rently outlying areas will occur regardless of the completion of the pro- posed pipeline. Revision of the existing system would include consider- able cost and disruption to urban areas, but more significantly, require a longer period to complete, increasing the likelihood of peak flow short- ages. CONSTRUCTION OF THREE PIPELINES The alternative of each agency building and operating its own pipe- line was investigated. Feasibility studies have indicated that the con- struction of three pipelines would cost several million dollars more than the proposed project. The operation and maintenance costs of three pipe- lines are additionally greater than for a single line. Environmentally, the impacts associated with the construction of three pipelines will be significantly greater than for the proposed single pipeline. From an engineering standpoint, there are a number of advantages associated with the proposed project that are lost with three separate pipelines. Perhaps the most significant of these is the flexibility of the proposed project. Excessive demands from any part of the system can be accommodated using the excess flow and storage capacity from an adja- cent agency. With three separate pipelines, the supply system of each agency is isolated and independent.
ALTERNATE PIPELINE ROUTES A variety of pipeline alignments was evaluated during preliminary engineering studies. The route selected represented the most efficient and direct alignment considering the requirements of each agency. Existing easements and property boundaries are followed to the degree possible. Selection of different alignments would require the utiliza- tion of additional property and require longer lines and increased costs. Additionally, selection of the proposed route avoided high slopes with possible stability problems and areas with structures or groves of trees.
X. RELATIONSHIP BETWEEN' LOCAL SHORT-TERM USES OF MAN'S ENVIRONMENT &-ID THE MAINTENANCE AND ENHANCEMENT OF LONG-TERM PRODUCTIVITY
Section X RELATIONSHIP BETWEEN LOCAL SHORT-TERM USES OF MAN'S ENVIRONMENT AND THE MAINTENANCE AND ENHANCEMENT OF LONG-TERM PRODUCTIVITY Strictly speaking, the proposed project involves minimal direct commitment of land. Most of the facilities involved will be placed underground and surface areas disturbed will eventually return to their natural state, permitting multiple use of the land. The immediate goal of the project is to compensate for the existing incapacity of the present water distribution system to meet peak flow demands. Actual shortages have not as yet occurred, and it is hoped to avert them by rapid completion of the project. Following standard engineering practice, and as accepted by CPO, the proposed pipeline will be accordingly oversized to meet the projected future requirements of the area. As such, the provision of water to fringes of the existing service area will facilitate its development. Whether such growth is beneficial or adverse to the area is a function of the adequacy of the long-range planning of each municipality. Examination of the adopted and proposed plans for the area indicates that the project growth will likely benefit the overall quality of the communities involved. Some loss of physical and biological resources in the area of probable growth will undoubtedly occur. Most of these areas are already stressed by human activity and are not known to contain unique features. Based on this analysis, it is not believed that the orderly develop- ment of the area as facilitated by the proposed project constitutes a threat to its long-term productivity.
In the final formulation of long-range planning, it is recommend- ed that particular concern be given to further development bounding Aqua Hedionda and Buena Vista lagoons. These areas are important com- ponents of the Pacific Coast Flyway and will be sensitive to development of the surrounding area. It is believed that provisions for the pro- tection and enhancement of these areas can be made compatible with the long-term human utilization of the surrounding region.
Section XI IRREVERSIBLE ENVIRONMENTAL IMPACTS Irreversible environmental impacts are believed to be relatively few. Perhaps the most irreversible change involves the loss of the archaeolog- ical sites found during the field work and the disturbance of those other f sites identified in this report. While these sites will be lost, pro- vision will be made for their orderly investigation at the option of cog- nizant agencies or societies. The commitment of resources involved in the implementation of this project is essentially irreversible, although not excessive. Any land-use conversions facilitated by the availability of water are not strictly irreversible, although on a practical basis they may be so viewed.
Section XI1 THE GROWTH-INDUCING IMPACT OF PROPOSED PROJECT WATER SERVICE AS AN INDIRECT FACILITATOR OF POPULATION AND ECONOMIC GROWTH The proposed pipeline project and metering stations will increase overall water quantities available to the Tri-Agency region, as well as the delivery of improved quality water to existing systems in order to distribute water more efficiently, meet current demand deficiencies, and serve projected future demands. Such improvements and system modifica- tions will facilitate the population and economic growth that has and is occurring, and that has been forecast to occur by CPO, San Diego County, and the cities and other jurisdictions within the Tri-Agency service area. Indirectly, better water quality will make urbanization more attrac- D tive since good water is of benefit to people, their homes, and to business and industry. Better water quality will make the Oceanside-Carlsbad-Vista area more attractive as a place to live, work, and play than if its water quality was allowed to become poor, unsafe, distasteful, or detrimental to public health -- in violation of public health standards, regulations, and laws. The project will also assure adequate supplies to meet current peak demands, and therefore prevent water shortages, water rationing, or inter- rupted water service to present water customers. LAND-USE PLANNING AND POLICY, AND THE USE OF WATER SERVICES AS A TOOL TO GUIDE OR LIMIT POPULATION AND URBAN GROWTH Traditionally, comprehensive urban and regional planning has been oriented to "planning for growth" -- instead of haphazard, helter-skelter, scattered suburban sprawl. Planning has been oriented to providing or- derly development, consistent with community goals and objectives, and
in assuring higher standards of design, aesthet'ic amenities, the provision of adequate public facilities and services (such as sewerage, water and flood control) , and streets , freeways and other urban transportation services, better housing, and the renewal of decaying central cities. Indeed, the thrust of city and regional planning during the past 30 years has been to plan for and assist orderly and rational urbanization. Such a planning ethic has necessarily presumed that "growth" was inevi- table, if not desirable; the problem was to plan for it rationally and regulate the process through various public laws and tools for the public health and welfare. The concept that populations and urban growth within a specific urban or regional territory can or should be limited to some optimum or maximum capacity is a relatively new philosophical thrust among con- cerned groups, throughtful citizens, and some professional planners. In respect to future water service needs by the year 1995, it is im- portant to remember that traditionally California -- particularly Southern California -- has been oriented to promoting and facilitating population growth. San Diego County has been a relative newcomer to the "Growthman- ship1' psychology. The human settlement, development, and continued population growth of a geographic region is not, however, CAUSED by the availability of a good domestic water supply, whether available locally by nature, or whether brought in by man from distant sources. If availability of large quantities of good water, locally and by na- ture, were the primary considerations for human settlement and hence urban development/"growth," then such cities as Spokane, Washington, Yakima, Washington, Pendleton, Oregon, and many other communities on the great Columbiz-Snake-Spokane River system of the Pacific Northwest should be the fastest growing urban areas of the west. 134
Climatically, the lands along the Columbia-Snake-Spokane River system in the Pacific Northwest are reasonably dry, and relatively attrac- tive (with a four-season climate) for human enjoyment. Climatically, the area is much more attractive than Seattle or Portland. It can therefore be concluded that the natural availability of water, even in relatively attractive climatic areas and regions of fairly good agricultural productivity, does - not attract the kind of urban population growth/development that is characteristic of selected areas of California. Growth in California is due to cultural, economic and social factors, and the availability of water -- consciously programmed by man -- makes con- tinued growth possible. On the other hand, should such water supplies be curtailed, future "growth" increments would be severely restricted. The superb climate of San Diego County provides a very strong attraction to people throughout the nation, and any attempts to prevent their movement to and settlement in the area would be most unpopular if not unconstitu- tional. With a "growth" momentum established, and supply systems already con- structed to meet the water requirements of additional people, the issues of "growth" management and urbanization policy of local or regional govern- ments concerned with land use and environmental issues become the focal points for public policy decisions. Since the traditional regulatory controls over land use -- namely zoning ordinances and subdivision ordinances -- have been weak, and the tools of capital improvements programming and budgeting could be used to induce private development in certain areas and inhibit private develop- ment in others, there has evolved a new "package" approach to directing, guiding, and/or inhibiting new urban development. Besides public acquisition of land, agricultural preserves, open space planning and zoning, the acquisition of development rights
(generally known as scenic easements), etc., environmental protection legislation and the ethics of ecology/conservation have gained wide public support, conceptually, to develop stronger techniques to manage, if not restrict or limit, "urban growth." 11 These new techniques, perceived as a package" of tools once a policy for such action has been declared by the people af an area through the electoral process, include the provision of water, sewer- age and other essential utilities as primary tools in determining the location and ultimate extent of urbanization and population capacity to be serviced in a given geographic area. Thus the political issue of "growth limitation," perceived as a desirable long-range environmental protection goal for the San Diego Region (many citizens fear the consequences of a Los Angeles-Orange County growth development syndrome), has focused upon controlling the key public services essential to support more people and industry: water and sewerage services. If one wishes to stop urban growth in a specific territory, the rationale of such a goal suggests the strategy to stop additional water supplies from being provided, and stop the extension of water services to adjacent areas or communities where a strong market demand for hous- ing and commerical development exists. Such a strategy has been perceived as one of the key decision and policy points to actually control land use and additional land develop- ment into urban uses, and thus limit the population level that can be housed and supported in a given territory. Alternative policies to control and limit population growth and urbanization are now being considered by the County of San Diego, the
Comprehensive Planning Organization, and other jurisdictions within the region. Such policies and actions are not presently the responsibility of the SDCWA or the Tri-Agencies; however, the SDCWA and the Tri-Agencies through future legislative and other governmental actions at the state and regional level may be required to implement various water pricing, ex- tension, and supply/service levels in order to assist in achieving regionwide growth management policies, plans and programs. Urban growth management strategies and policies have recently focused upon the creation of a strong "Open Space'' plan in order to define land areas deemed worthy to be preserved from future urbanization. Such plans have been prepared by CPO and San Diego County and their future implemen- tation success will depend upon various policy, legislative, and land-use regulations and controls. One such implementation tool which bears upon managing future growth and preventing the urbanization of prime irrigated agricultural lands is the Agricultural Leaseback approach, recommended for consideration in the CPO Open Space Plan. The Agricultural Leaseback approach would seek legislative author- ity to issue revenue bonds to purchase prime agricultural land from farm owners, and lease such lands back to the owners or sub-tenants for agri- cultural operations, for long time periods -- perhaps for 20- to 99-year lease terms, Lease revenues generated by the agricultural operators would be used to amortize the revenue bonds issued to purchase the lands. With a possible food production crisis coming in the next few years, this innovative concept to preserve prime farm lands from tract housing
and shopping center development in specific geographic and regional areas deserves careful consideration by local officials and concerned groups and citizens as an additional tool in evolving an economically and environ- mentally sound ''growth management" program for the San Diego region, the Tri-Agencies water service area, and respective cities. 4:
GEPEXAL BIBLIOGRAPHY California Division of Mines and Geology, Evolution of the California Landscape. Bulletin 158, 1952. Geology of Southern California. Bulletin 170, 1954. Geologic Map of California, San Diego Sheet. 1962. Geologic Map of California, Santa Ana Sheet, 1965. Urban Geology Master Plan for California, 1971. California Native Plant Society, 17 August, 1971. P. 46. University Arboretum, University of California, Davis 95616. Carlsbad City Planning Commission, General Plan Land Use Element, September 11, 1974. Center for P-egional Environmental Studies, California State University, San Diego, California. The Santa Margarita Ecological Reserve - Description, Present Disposition and Recommendations for Future Use. 21 March, 1973. Comprehensive Planning Organization with the San Diego Region, t?ater, Sewerage and Flood Control Systems Plan and Implementation Program 1973-1974, Job 1202. PLAN, Existing Trends 1975, prepared for member agencies June 1973. 3m/7804/ss. WJ16-73. San Diego County 1971 Generalized Land Use Map, July 1972. , Development with Ground ~rans~ortatiin Systems - Noise Contours for the San Diego Region, December 1973. Comprehensive Planning Organization of the San Diego Region, A-95, The Clearinghouse Review Process - prepared for member agencies lM/7931/4-74. -9 Comprehensive Plan for the San Deigo Region, Vol. 1, Goals. March 1974. 3M/7433/SS.WJ/3-74. , Analysis of the Controlled Trends Regional Development Alternative, April 1974. Open Space Plan and Implementation Program, April 1974. Population Growth Policy Study - Sensitivity Analysis - April 1974.
GENERAL BIBLIOGRAPHY (continued) Population Growth Study - Influencing Population Growth: An Analysis of Regional Growth Strategies, May 1974. Population Growth Policy Study - Environmental Impacts of Population Growth in the San Diego Region, June 1974. Population Growth Policy Study - Fiscal Impacts of Population Growth, July 1974, Population Growth Policy Study - Economic Impacts of Population Growth Summary Report, August 1974. Sanpat Citizen Hearing Board Report Recommendations and Findings. August 1974. Doscher, Marian 0. and Weddell R.P. under Copley International Corporation - Land Uses, Population, and Employment, San Luis Rey, Santa Margarita, and San Juan Hydrologic Units 1970-2020, Prepared for the Joint Administration Committee of the Santa Margarita and San Luis Rey Watershed Planning Agencies, February, 1973. - Environmental Development Agency, Natural Resources Inventory of San Diego County, Section 1-7. Program developed for Integrated Regional Environmental Management Program, no date. Hammer, Silver, George Associates, Regional Housing Market Analysis, Summary Report, submitted to San Diego County Comprehensive Planning Organization. September 1973. McEuen, R.B. and Pinckney, C.J., Seismic Risk in San Diego, Transactions of the San Diego Society of Natural History, Vol. 17, No. 4, July 1972. Montgomery, James M., Consulting Engineers Inc. Preliminary Progress Report No. 2 - Filtered Water Distribution Study, prepared for SDCWA, November 1972. Report No. 3, Filtered Water Distri.bution Study, January 11, 1973. Report No. 4 - Treatment Costs and Alternative Water Rates, prepared for SDCWA, February 8, 1973. Report No. 5, Filtered Water Distribution Study, May 10, 1973. Report No. 6, Filtered Water Distribution Study, September 13, 1973,
GENERAL BIBLIOGRAPHY (continued) Report No. 7, Filtered Water Distribution Study, September 13, 1973. Technical Report - Water, Wastewater and Flood Control Facilities Planning Model, submitted to San Diego Comprehensive Planning Organization. January 1974. Alternative Water Treatment Methods, prepared for San Diego County Water Quthority, February 1974. San Diego County Water Authority Filtered Water Distribution Study - April 1974. Mudie, Peta J., State of California Resources Agency, Department of Fish and Game, June 1969. A Survey of the Coastal Wetland Vegetation of North San Diego County. Wildlife Management Administration Report No. 70-4. Munz, Philip A. and David D. Keck, 1968. A California Flora. University of California Press, Berkeley and Los Angeles. p 168. Meuner, Edward J., 1974, Economic Analysis of Filtered Water Alternatives - paper submitted to Board of Directors, San Diego County Water Authority. Nolte, George S. and Associates, Drainage and Flood Control Background and Policy Study. Vol. 11. A Computer Methodology for Determining Urbanization's Drainage Consequences. Job No. 2810. May 1970. Drainage and Flood Control Background and Policy Study. Summary Report for CPO, San Diego County, California. Job No. 2810. May 1970. Poway Municipal Water District Environmental Impact Report. Water Transmission Mains 1972-1973. December 19, 1972, Radburch, D.H. and Crowther, K.D., Landslide Susceptibility in San Diego County, Open file Report U.S. Geological Survey, 1970. San Diego County. 1970 Census Tracts with Subregional Areas prepared for Comprehensive Planning Organization. San Diego County Planning Department, San Diego County General Plan - presented to County of San Diego, July 10, 1974. San Diego City Planning Commission. Progress Guide and General Plan for the City of San Diego. Adopted January 27, 1972.
GENERAL BIBLIOGRAPHY (continued) San Diego General Plan Advisory Cormnittee, Progress Guide and General Plan for the C5ty of San Diego, City Resolution No. 191085, Adopted on July 20, 1-967. Santa ?fargarita and San Luis Rey Watershed Planning Agencies - Joint Administration. Committee. Comprehensive Water Quality Nanagenent Study - Vol. I 1974. Santa Margarita and San Luis Rey Watershed Planning Agencies - Joint Administration Committee - Summary Report and Impact Statement, March 1974. Schnalsel, P.B. and Seed, H.B., Accelerations in Rock for Earthquakes in the Western United States, Vol. 63, April 1973. Sedway/Cooke, San Diego County Initial Growth Policy, submitted to the County of San Siego Environmental Development Agency. August 7, 1974. Soil Conservation Service, Soils of San Diego County, 1971. Smith, Gregory S. and Gerald J. Fakus of Tetra Tech, Inc. Basin Coastal Analysis for Santa Margarita - San Luis Rey Watersheds and Camp Pendleton. Prepared for Jo'int Administration Committee of the Santa Pfargarita Watershed Planning Agency and San Luis Rey FJatershed Planning Agency - Contract No. TC307, September 1972. Vista, City of, Conservation Element, A Preliminary Sketch. No date. Vista Planning Commission, Land Use Element Amendment 1973-1974. , General Plan - City of Vista, Descriptive Text, Resol.ution No. 67-67, October 3, 1967. , Addition of Open Space Element, Resolution 73-18, April 2, 1973. -9 Community Physical Problem, Resolution 73-92, July 2, 1973. Woodward-Envicon, Inc., Draft EIR, Mission Gorge Filtration Plant and Pipe- line No 4 Improvements, Prepared for SDCWA, September 1973.
Appendix A NOISE CRITERIA
Appendix A NOISE CRITERIA INTRODUCTION Noise has variously been defined as "unwanted soundt' or "sound with- out value." Both these definitions implicitly recognize the subjectivity inherent in the definition of noise. Explicitly, however, sound affects the full range of human activity. The sound environment can be physically described with high precision, and physiological effects can be predicted with varying degrees of accu- racy. Phsiological effects may vary from permanent hearing loss to tempo- rary constriction of blood vessels, depending on the level and duration of sound. Thus, the puhlic health implications may vary from serious to minor. However, even apparently minor effects do not justify ignoring the effects of noise on the quality of life nor the more subtle or indirect influences of noise on human behavior and performance. Community response to environmental noise is influenced by collective and individual attitudes toward the sources of noise, and by opinions as to whether or not anything can be done to reduce or eliminate the noise. Changes have occurred as the public has come to understand that in many in- stances something can be done to abate or control environmental noise. It is the responsibility of public agencies to decide when and what should be done to control environmental noise. BACKGROUND This section provides background information and definitions to aid in understanding the 'information presented in the following section. There
are three primary factors which are used to describe environmental noise and its impact on man -- intensity, frequency spectrum, and variation with ', time. Airborne sound is a fluctuation of air pressure above and below at- mospheric pressure. The magnitude of the pressure fluctuation determines the intensdty of sound and the number of fluctuations per second is the frequency. The range in pressures is so great that a logarithmic scale is used to describe sound intensity. The sound pressure level is given in decibels and is defined as: Sound Pressure Level, dB = 10 LoglO (pipo )' The value of the reference pressure, Po, is twenty micro-Newtons per square 2 meter (20uN/m ), which is approximately the threshold of hearing. The unit of measurement of frequency is the cycle per second or Hertz (Hz). Most of the sounds heard in the environment do not consist of single frequencies, but of a mixture of frequencies, each with a differing inten- sity or level. Human hearing is not equally sensitive to all frequencies. Generally, it is less sensitive for frequencies below 1000 Hz and to a les- ser extent, for frequencies above 5000 Hz. Fortunately, a relatively simple method of weighing the frequency components of environmental noise and com- bining the results into a single number has been found to correlate well with human response to environmental noise other than that generated by aircraft operations. The weighting system most commonly used is 11 A 11 weighting, and the resultant number is called the "A-weighted sound level." The A-level in decibels is expressed "dBA," and the A-level of a sound source is conveniently measured using a sound level meter that in- cludes an electrical filter corresponding to the A-weighting curve. The level of environmental noise varies continuously above a relatively stable base created by all distant and continuous noise sources (such as wind, traffic and industry) the constituents of which cannot be readily identified, and which slowly varies with the daily cycle of human activity. Superimposed on this slowly varying background is a succession of noise
events of shorter duration from transient activities such as aircraft fly- over, single vehicles, etc., which cause more rapid variation in the over- all noise level. Variability and unpredictability are two characteristics of the noise environment frequently identified as the cause of disturbance and annoyance. It is easier to adapt to a relatively steady noise level, even if it is fairly high, than it is to adapt to a noise level that varies widely and un- predictably in intensity. Noise generated by construction activities is an example, but an even more dramatic example is the noise generated around air- ports. A statistical description commonly used in characterizing environ- mental noise is the "level exceeded for a stated percentage of time." For example, noise levels exceeded 10 percent, 50 percent, or 90 percent of the time can be derived from histograms of noise levels. These noise levels are abbreviated symbolically as LlO, L50, and LW, respectively. The L90 level is sometimes called the residual noise level, and the L level is 50 referred to as the average noise level. NOISE CRITERIA This section presents background information and data useful in evalu- ating the current noise environment and the impact of any changes occurring as a result of proposed developments. Most criteria currently in use to evaluate or control environment noise are formulated from combinations of data on physiological effects, and on community complaints and annoyance. Another consideration might be the preference of the general population. These preferences are shown in Table A-1. The physiological effects of noise normally considered in establish- ing standards or criteria are hearing damage, speech interference, sleep interference, physiological stress, and task interference. The degree of
Table A-1 POPULATION PREFERENCES REGARDING tTOISE LEVELS NOISE LEVELS (dRA) DAY NIGHT TYPE OF AREA WANT ACCEPT WANT ACCEPT Rural 35 4 5 2 5 3 5 Suburban 4 0 5 0 30 40 Urban, residential 4 5 5 5 35 45 Urban, residential plus shops 5 0 6 0 4 0 5 0 Commercial 55 65 4 5 5 5 Industrial 6 0 7 0 50 60 Water recreation, restricted 4 5 45 3 5 3 5 Water recreation, unrestricted 55 5 5 45 4 5 Wilderness' 30 30 20 2 0 - -- Source: Anonymous, "Report to the California Legislature on Noise," prepared by the California State Department of Public Health, January, 1971.
certainty in the dBA levels for these effects, given in Table A-2, varies from good to poor. The levels given for hearing damage are well documented; the upper limit of 90 dBA is the 8-hour continuous exposure'limit allowed under the Occupational Safety and Health Act of 1970. This degree of cer- tainty does not exist for task interference. The extent and type of community response which may be expected from various average noise levels other than airport noise is shown in Figure A-1. This information is based on community complaint and survey data. Thus, this information must be interpreted within the context of community attitudes as discussed in the introduction. Federal standards from the U.S. Department of Housing and Urban Develop- ment (HUD) and the U.S. Department of Transportation (DOT) are presented, respectively, in Tables A-3 and A-4. The DOT standards are design goals for traffic-generated noise and the predicted or measured noise level, LlO, is based on peak hour traffic. HUD criteria do not discriminate as to land-use category because the primary concern is suitability of living quarters. These federal criteria are based upon the aforementioned data on the physio- logical effects of noise, plus community response data.
Table A-2 . ESTIMATES OF MAGNITUDE OF NOISE EFFECTS -- - - - - - NOISE LEVEL (dBA) EFFECTS MODERATE APPRECLABLE - -- Hearing Damage Risk 70 9 0 Speech Interference 45 . 60 Sleep Interference 40 70 - Physiological Stress 70 90 Task Interference 55 7 5 Source: Bolt, Beranek and Newman, Dec. 1971. Noise from Construction Equipment and Operations, Buil.ding Equipment and Home kpliances. NTIS as National Tech. In- formation Document 300.1.
00 TYPE OF RESPONSE Disturbs Rest or Relaxation 90 terferes with Conversation 80 Much Annoyed 70 60 50 4 0 0 2 0 40 60 80 LOO EXTENT OF COMMUNITY RESPONSE (percent) Figure A-1 COMMUNITY RESPONSE TO NOISE
Table A-3 I DOT DESIGN NOISE LEVEL/LAND-USE RELATIONSHIPS LAND-USE DESIGN NOISE . CATEGORY LEVEL - LlO* DESCRIPTION OF LAhQ-USE CATEGORY A 60 dBA Tracts of lands in which serenity and quiet are of extraordinary significance and serve an important public need, and where the preservation of those qualities is essen- tial if the area is to continue to serve its intended purpose. Such areas could in- clude amphitheaters, particular parks or portions of parks, or open spaces which are dedicated or recognized by appropriate lo- cal officials for activities requiring spe- cial qualities of serenity and quiet. B 70 dBA Residences, motels, hotels, public meeting rooms, schools, churches, libraries, hospi- tals', picnic areas, recreation areas, play- grounds, active sports areas, and parks. C 75 dBA ~evelo~ed lands, proper ties or activities .not included in categories A and B above. D -- For requirements on undeveloped lands, see paragraphs S.a(S) and (6) of PPM 90-2. E** 55 dBA Resfdences, motels, hotels, public meeting rooms, schools, churches, libraries, hos- pitals, and auditoriums. * Criteria are applied at boundary, peak traffic hour. ** See method.of application. Interim Noise Standards and Procedures for Implementing Section 101(1) of Title 23, U.S. Code, Federal Highway Administration, Policy and procedure llemorandum (PRl) 90-2, April 1972. 9'
Table A-4 SUMI.IARY OF HUD KOISE CRITERIA* GENERAL EXTERNAL EXPOSURES** dBA UNACCEPTABLE Exceeds 80 dBA 60 minutes per 24 hours (L ). 4 9 Exceeds 75 dBA 8 hours per 24 hours (L33). (Exceptions are strongly discouraged and require a 102(2)C environmenral statement and the Secretary's approval.) DISCRETIO?TNZY - MOmlALLY UNACCEPTABLE Exceeds 65 dBA 8 hours per 24 hours (L~~). \ 9 Loud repetitive sounds on site. (Approvals require noise attenuation measures, the Regional Administrator's concurrence and a 102(2)C environmental statement.) DISCRETIONARY - ROREIALLY ACCEPTABLE m Does not exceed 65 dBA more than 8 hours per 24 hours (L ). 3 3 ACCEPTABLE Does not exceed 45 dBA more than 30 minutes per 24 hours. *Anon., Noise Abatement and Control: Departmental Policy, Implementation, Responsibilities, and Standards. U.S. De~artment of Housing and Urban Development, August 1971. . **Criteria are applied.at boundary.
Appendix B REPORT ON THE ARCHAEOLOGICAL RESOURCES OF THE TRI-AGENCIES PIPELINE
INTRODUCTION On October 27 and 30, 1974, Stanley R. Berryman and M, Jay Hatley conducted an archaeological survey of the proposed Tri-Agencies Pipeline at Carlsbad, California.
settinq: The Tri-Agencies Pipeline extends from Chestnut Avenue in Carlsbad eastward to La Mirada in San Diego County, Topographically it consists of bluffs, ridges, and valleys, overlooking Agua Hedionda Laggon, Parts of the pipeline are intersected by intermittent streams, zlevations range from a low of approximately 165 feet to a high of 653 feet, Two distinct plant communities were recognized, those in areas that had been used for agricultural purposes and those left natural, The former consisted of non-native grasses and mustard: the later of coastal chapparal, black and white sage, chamis, manzanita, sumac, scrub oak, coastal oak, poison oak and deerweed. Methods of Surveyinq: -- - The survey team transversed the entire length of the proposed pipeline, This was accomplished by means of an on- foot reconnaissance, Areas that had a high probability for sites were given special attention, This includes such areas as ridge tops, saddled areas, valley floors and the less steeply sloping sides of the hills.
-1- Culture History: While earliest man nay have entered this continent as early as 20,000 years ago (Carter 1957, Orr.1956, Crook -- et,al, 1958, Harrington and Simpson 1961), the oldest definable occupation occured between 10,000 and 9,000 3.C. (Willey 1970 ,Yaynes 1964). This latter has been referred to as the Paleo- Indian Horizon (~avis -- et.al. 1969), the San Diego County regional aspect of which is termed San Dieguito (Rogers 1929, Warren and True 1961, Davis -- et.al, 1969). From approximately 6,500 B,C, until 5,000 B.C. intrusions of peoples from the deserts to the coast (Warren -- et.al. 1961, Wallace 1962) resulted in a pattern known as the Early Milling Horizon, which is characterized by the La Jollan Aspect (Rogers 1966), the Pauma Complex (True 1958), and the Amargosan Aspect (Wallace 1962). Between 3,000 and 1,000 B.C., settlement patterns along the coast changed and the groups broke into smaller units, which lived either inland or along salt water bays (wallace 1962, Warren -- et.al. 1961). i With the smaller bands establishing new transhumant land- use patterns between the coast, mountains, and deserts, came an influx of new cultural elements (~ogers 1966, Warren and True 1961, Warren -- et.al. 1961). Between approximately 300 A.D,
• right 1965), and 1,000 A.D., the Late Milling Horizon replaced the Early Milling pattern (~ogers 1945). The Late Milling Horizon land-use patterns are far more complex than those of the Early Milling Horizon, It is apparent that village and camp sites reflect deliberate transhumant and seasonal exploitative patterns, These later peoples rnain- tained one or two seasonal villages which were surrounded by a variety of resource camps such as acorn processing stations, rock quarries, agave roasting stations, etc, The Late Milling Horizon continued until the time of Spanish contact in 1769 which began the breakdown of the earlier patterns,
GENERALIZED CHRONOLOGY AND SEQUENCES OF SAN DIEGO COUNTY ARCHAEOLOGIC CULTURES 1,769 A.D. s (coastal) (desert) La Jollan I11 Amargosan La Jollan I1 La Jollan I 11,000 B.C. I Early Hunting Traditions 20,000 B. C. Unknown Late Milling Archaic Early Milling Archaic Paleo- Indian First Ame rica Cultures
Survey Results: Five archaeological sites on or near the proposed pipe- line were found by the survey team. One additional site near Appean Nay in Carlsbad was known to the archaeologists from previous work in the area. It has a Museum of Man number of W-136 and a San Diego State University number of SDi-631, It is located far enough to the northwest to not be affected by any construction of the pipeline. The sites found during the survey are numbered consecutively from the west to the east. Site I: -- This site is located on the southwest side of a small knob, west of the pipeline route, It is a stone fort with stacked walls. It has two sides of stacked granitic cobbles, while the other two walls consists of large granitic boulders. It measures 5 feet long east/west by 4 feet wide north/south, the walls are 2% feet high. There is no soil in the floor of the structure, it is rather lined with granitic cobbles. There is no midden soil in the area surrounding the structure. NO evidence of lithic flakes, tools, pottery or shell could be found. It is most likely that this structure was used entirely for defensive purposes (~ay 1974) and would therefore lack the normal artifactual assemblage.
Site 2: -- This site is located on the south slope of an east-west trending ridge. The vegetation surrounding the site is typically coastal chaparral, The soil is a light tan in color and is a - fine-grained sandly loam. This site is a small workshop, covering an area of 15 feet in diameter, The assemblage involves six felsite flakes. Three exhibit heavy grey-green patina indicating San Dieguito antiquity, and the remaining three lack patina which indicates a Luiseno aff 1 iation, Site 3: -- This site is almost tangent to the survey line and is located on the west side of a saddle, on the lee side of a knob on the saddle. Its location protects it from the ocean breezes of this area, There are two distinct plant communities on this site, which are divided by the dirt road that bisects Site 2:a dense coastal chapparal community on the west and a grass and mustard community on the east. The soil is light brown to tan in color. It is a medium to fine grained, well sorted, sandy loam, It can not be described as typical organic midden, but shell fragments are abundant, Site 3 is a large oblong shaped campsite, It measures 280 feet north/south by 240 feet east/west. Part of the site is disturbed by the dirt road which has been graded to a depth of 10-12 inches. Along and through the road there are numberous
scattered hearth stones, these make-up four badly distrubed hearths. There is also a wide distribution of chione and pectin shells along the surface. Of the artifacts found there were: 3 choppers, 1 scraper, and 2 potsherds. Nuch of the surface material has probably been collected by 'pothuntersl'. Some depth is indicated by the road cut, by rodent burrows, and by a small pit in the northern area of the site, but it is undoubtedly deeper than 12 inches. Site 4: - This site is located on the survey line in a small valley. It is just south of Agua Hedionda Creek, which is an intermittent stream. The valley appears to have been farmed at one time in that the plants consist of some sage, grasses and mustard: there is a stand of oak off the site to the west. The soil is a medium brown, well sorted, small to fine grained. There is a high content of organic matter present, probably due to decomposing plant matter. Site 4 is oblong in shape and measures 160 feet north-south by 115 feet east-west. It consists of a high concentration of chione and pectin shell. The only artifact found was a single quartz flake. There is\ considerable depth indicated by rodent burrows. Much of the shell on the surface was probably brought up by plowing.
This site is somewhat of an anomoly in that it appears to be somesort of shellfish processing station, This would have been an excellent location for a campsite, but there is little evidence of any prolonged activity, Site 5: -- This site is located on the survyed line, It is on the south-west side of a north/west trending ridge, Its location is east and somewhat higher than adjacent Site 4, Most of the site is covered with short grasses, although there is some mustard, buckwheat, chamise, and scrub oak, The soil is a tan, well sorted, fine-grained sandy soil, Although, this site is located on the side of a ridge, it is not subject to much of erosion, Site 5 is made up of two loci, Locus A is circular and has a diameter of 120 feet, It consists of a moderately heavy concentration of chione and pectin shell, The artifacts include 3 flakes and 1 potsherd, Some fire cracked rock was noted on the surface, Depth was indicated by the material being pushed out of rodent burrows. Locus B is 120 feet down slope (west) of Locus A, It has an oblong shape 10 feet north/south by 5 feet east/west, There is chione and pectin shell on the surface as well as 1 potsherd and 2 flakes. Enough fire-cracked rock is exposed to indicate this was probably a hearth area,
Site 5 most likely relates to Site 4 in some as yet undetermined way, They both may indeed be seperate sites or just different use-area of the same area. Cultural Association of Sites 1-5: Based upon surface survey all the sites, except Site 2, on the pipeline route can be assigned to the Late Archaic (~uiseno) cultural horizon (see section on Culture History). Site 2 contains lithic material representative of both Paleo- Indian an Dieguito) and Late Archaic Horizons, Scientific Significance - of Sites -0 1-5 Environmental Impact - on Sites 1-5: - i significance I impact
Research Potential: Site I: -- This site is extremely unusual in Luiseno territory, Such sites in San Diego County are rare and very valuable to the study of prehistoric warefare patterns, Protection of these sites is very important, Site 2: No research potential, Site 3: -- This moderate rated site should be able to add valuable information concerning how this type of site fits into the transhumant patterns of northern San Diego County, Information on intersite use areas and ecological adaptation can also be gained hang 1968)- Specific information on dating, environment, and food sources can be gained by the following types of analysis: pollen, shell, Ph soil testing, and radiocarbon tests. Sites 4 and 5: --- Because of their close proximity and possible inter- relatedness, Sites 4 and 5 should be considered together in this section. Since these sites, based upon surface material, are unusual, they will be of considerable value to science and California heritage. Such information as Land-use patterns, cultural chronology, micro-faunal and pollen studies, obsidian
hydration rates, detailed intersite tool distribution analysis by mapping, and other stuaies can be gained, Mitigation Recommendations: It is strongly recommended that all access road along the route be closed to unauthorized traffic, This would protect Site 1 from destruction by off-road vehicles and pothunters. Site 2 is of little value and will not need mitigation beyond the survey form. Site 3 will probably receive direct impact from construction equipment along the pipeline, Such areas should be micro-mapped i and salvage excavated prior to the pipeline construction, This would probably involve a series of transects mapped at a ll':lt scale, Excavation pits and trenches should be dug-both by hand and with a mechanical backhoe, The close association of sites 4 and 5 and the direct impact to be caused by the pipeline necessitate that these sites be dealt with together, The surface distribution of artifacts should be micro-mapped on a 1':l scale, ~ll artifacts should be plotted, catalogued, and recovered for storeage at San Diego State University. The impact area should be salvage excavated in test units and trenches, Mechanical backhoe trenching may be used as a supplement to the other excavation, . Backup work in all of the excavations should include pollen analysis, radio-carbon dating, faunal analysis, anthropo-
metric studies of any human remains, ceramic analysis, and possibly obsidian hydration ratings. These would be included in the field salvage report which would be submitted about 30 days after completion of the excavations.
Sources Cited: Bright, M, 196 5 California Radiocarbon Dates, University of California at Los Angeles. Archaeoloqical Survey Annual Report, pp. 363-376, Carter, G, 1957 Pleistocene Man at San Diego. John Hopkins Press, --- Chang,K, 1968 Settlement Archaeology, Natuional Press, Davis, E.L., Cog, Brott, and D.L. Weide 1969 The Western Lithic Co-Tradition, - San Diego Ruseurn Papers $5. - San Diego, Haynes, C,V. 1964 Fluted Projectile Points: Their Age and Dispersion. Science. 45: 1408-1413, Washington D, C, Rogers, M,J. 1945 Outline of Yuman Prehistory. Southwestern Journal - of Anthropology, Vol 1 #2:167-198. 1966 Ancient Hunters --- of the Far ?Jest, Copley Press: San Diego Union-Tribune Publishing Company, True, D,L. 1958 An Early Complex in San 3iego County, California, American Antiquity, 23 : 255-263, Warren, C.N. and D,L. True 1961 Early Gathering Complexes of Western San Diego County: Results and Interpretations of an Archaeological Survey. Archaeological Survey Annual Report for 1960-61. 7-106, UCLA. -- - Warren, CON. 1961 The Southern California Milling Horizon: Some Comments, American Antiquity, 32:233-36, Wallace, W,J, 1962 Prehistoric Cultural Development in Southern California Deserts, American Antiquity. 28:172-180, Willey, G, 1970 Introduction to American Archaeo?ogy, Prentice Hall, Cliffs, New ~ersey,