Water Report C › waterrights › water... · ter District, and Santa Ynez River Water...

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Santa Ynez River

Cuyama River

Sisquoc River

Santa MariaRiver

San Antonio Creek

TwitchellReservoir

Surface WaterSurface water refers to water resources that flow or are stored in surface channels (streams and rivers, orlakes and reservoirs). Surface water can be naturally occurring, or can be created or altered through humandesign. A surface reservoir is formed when a dam is built to trap natural flows along a river and to tempo-rarily store water behind the dam in the reservoir. Water can then be released in a controlled fashion forflood control, recreational purposes, or as needed for water supply. The land area that collects water whichfeeds into surface flows, such as creeks and rivers, is called a watershed. A watershed includes the areas upto the mountain ridges that collect rainwater, the valleys with streams within these areas, and the lakes wherethe water flows are stored.

LakeCachuma Gibraltar

Reservoir

RiversJamesonLake

Santa Ynez River

General Information

In Santa Barbara County there are several riversthat flow from back-country watersheds into theocean. The flow of the rivers in Santa Barbara Countyis highly variable with more years of low and inter-mediate flow than years with high flow. In SantaBarbara County flow is dependent on rainfall, asthere is little base flow and no significant snow-melt. The years within the top 25% for rainfallcreate most of the volume in Santa Barbara Countyrivers, so during normal years many streams aredry throughout the summer and fall. Four reser-voirs have been built to capture these surface flowsfor a variety of uses.

Santa Ynez River

Geology, Topography, Location:

The Santa Ynez River watershed, located in the centralpart of Santa Barbara County, is about 900 squaremiles in area. The Santa Ynez River originates inthe San Rafael Mountains in the Los Padres Na-tional Forest, at an elevation of about 4,000 feetnear the eastern border of the county. A smallportion of the Santa Ynez River watershed lies inVentura County. The river flows westerly about 90miles to the ocean, passing through Jameson Lake,Gibraltar Reservoir and Lake Cachuma. The ter-rain on the south side of the river rises steeply to

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Water Resources of Santa Barbara County

the crest of the Santa Ynez Mountains. These moun-tains range in elevation from about 2,000 to 4,000feet and separate the Santa Ynez River Basin fromSanta Barbara and the South Coast. The north sideof the basin is formed by the Purisima Hills andSan Rafael Mountains, which range in elevation from1,000 to 6,000 feet.

As the river descends from higher elevations, it passesthrough a narrow trough between the mountainsjust upstream of Lake Cachuma. Below LakeCachuma, the river passes along the southern edgeof the Santa Ynez Upland and flows past the broadpart of the valley near Buellton. West of Buellton itflows through a narrow meandering stretch to theLompoc Narrows and emerges onto the broadLompoc Plain before it empties into the PacificOcean at Surf Beach.

The river is characterized by both narrow channelsections on bedrock and broad alluvial floodplainsmore than 2,000 feet wide near Solvang and Lompoc.Near Bradbury Dam, the active channel is approxi-mately 400 feet wide. Further downstream nearthe confluence with Alamo Pintado Creek, the ac-tive channel is more than 400 feet wide.

Flow Rates/Flooding History:

Streamflow in the Santa Ynez River watershed isderived primarily from surface runoff and shallowgroundwater inflow following storm events, whichvary greatly in frequency and intensity from year toyear. The soils, geology, and topography of thewatershed create relatively rapid runoff conditions,with streamflow hydrographs showing a rapid riseand fall in response to precipitation. As a result,the Santa Ynez River is characterized as a “flashy”system, with streamflow rising and falling in re-sponse to precipitation.

When water rights releases are made from Gibraltarand Bradbury Dams in the summer months, thereare flows downstream of Gibraltar Reservoir andLake Cachuma. In addition, the Lompoc RegionalWastewater Treatment Plant discharges approximately3.5 million gallons of treated wastewater per day,

creating almost year-round flow from the plant facilityto the ocean.

Several major tributaries downstream of BradburyDam contribute significant flows to the lower SantaYnez River, including Santa Agueda, Alamo Pintado,Zaca, Alisal, Salsipuedes, and San Miguelito Creeks.

Data taken from several stream gages demonstrateyear to year variability in streamflow within thewatershed. The data also demonstrate the inter-mittent nature of streams in the watershed, withhigh flows occurring in the winter and the likeli-hood of little or no flows in the summer. Annualmedian flow from the Santa Ynez River into LakeCachuma is 20,000 acre-feet (AF) with an annualaverage inflow of approximately 74,000 acre-feetper year (AFY). The maximum flow into Cachumais approximately 500,000 AFY. The highest flow inthe Santa Ynez River occurred near Solvang duringthe 1969 floods when flows reached 82,000 cubicfeet per second (cfs).

Water Use:

In the Santa Ynez River Basin there are three stor-age reservoirs that divert Santa Ynez River water tousers primarily on the South Coast of the county.

Juncal Dam was completed in 1930 and is onesource of water for the customers of the MontecitoWater District. For more information see Reser-voirs section.

Receding storm runoffbringing rainwater from the

back-country

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Gibraltar Dam has been in place since 1920 cre-ating Gibraltar Reservoir, which serves as a watersupply for the City of Santa Barbara. For moreinformation see the Reservoirs section.

Bradbury Dam created Lake Cachuma in 1952and supplies water for the USBR’s Cachuma Project,which provides water to project members includ-ing the City of Santa Barbara, Montecito Water Dis-trict, Goleta Water District, Carpinteria Valley Wa-ter District, and Santa Ynez River Water Conserva-tion District, Improvement District #1. The Projectyield and downstream water rights releases serveover 290,000 people in Santa Barbara County andover 38,000 acres of cropland in Santa Ynez Valleythat supports a multimillion dollar agricultural in-dustry. For more information see Reservoirs sec-tion.

The watershed above Bradbury Dam is primarilyundeveloped open space under the jurisdiction ofthe Los Padres National Forest and the Lake CachumaCounty Park. Lands downstream of Bradbury Damare mainly in private ownership and fall under thejurisdiction of the County with the exception ofVandenberg AFB at the river’s mouth. Existing landuses in the lower watershed include irrigated andnon-irrigated agriculture, residential and urban areas(cities of Lompoc, Buellton, and Solvang along withseveral small towns), a federal prison, VandenbergAFB, cattle grazing, undeveloped open space, andmineral extraction (quarries, surface mines, oilfields). Crops grown in this watershed include winegrapes, beans, lettuce, broccoli, artichokes, andvarious flowers and trees.

The Santa Ynez watershed provides habitat to a widevariety of fish and wildlife species. Ten fish speciesare native to the river basin, four in freshwater andsix in estuarine habitats. Two species are listed asfederally endangered: steelhead trout and tidewa-ter goby. Fifteen introduced species have popula-tions in the basin, most of which are game speciesor baitfish that were originally planted in LakeCachuma, but have since spread. Other species ofnote include the California red-legged frog, least

Bell’s vireo, the southwestern willow flycatcher, andthe southwestern arroyo toad.

State, federal and local agencies signed a Memo-randum of Understanding (MOU) in 1993 for Co-operation in Research and Fish Maintenance onthe Santa Ynez River downstream of Bradbury Dam.Since then, a program of cooperative fisheries in-vestigations and basin management planning hasbeen underway in the Santa Ynez River. The goal ofthe plan is to identify and evaluate potential man-agement actions that will benefit fish and otheraquatic resources in the lower Santa Ynez River.

Sisquoc River


The Sisquoc River receives runoff from a watershedarea of approximately 470 square miles. The wa-tershed of the Sisquoc River is defined by the north-westward-trending Sierra Madre Mountains on thenorth and the westward trending San Rafael Moun-tains on the south. The San Rafael mountains riseto 6,828 feet (U.S. Bureau of Reclamation, 1951).Most of the Sisquoc River drainage lies within theboundaries of the Los Padres National Forest.


Streamflow in the Sisquoc River has averaged 54.6cfs for water years 1942-1998. Flows of up to 33,600cfs have occurred in extremely wet years like 1983,however it is not uncommon for long periods of noflow to occur each year. Floods from the SisquocRiver basin are short in duration with relativelyhigh peak discharges. Shallow erodible soils, steepslopes, and high rainfall combine to make pos-sible destructive flood flows whenever the cover isdestroyed or reduced in density (U.S. Departmentof Agriculture, Forest Service, 1951).

Water Use:

Land use occurring along the reaches of the rivervaries from wilderness to agriculture. Hiking trailsand campgrounds are established in the section

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within the Los Padres National Forest. The remote-ness of this region allows for relatively pristine,diverse and abundant wildlife habitat. The SisquocRiver is known to provide habitat to native troutand is within the range of the peregrine falcon (Jonesand Stokes Assoc, Inc. and Leeds, Hill and Jewett,Inc., January 1979).

The Sisquoc Plain is intensely cultivated. Land usesalong lower reaches of the river include vineyards,wineries, sand/gravel mining, and cattle ranches.The Sisquoc is unregulated so irrigation occursthrough pumping from wells along the river. Cropsgrown in this area include cauliflower, broccoli,carrots and strawberries.

Cuyama River


The Cuyama River drains an 1,140 square milewatershed area that includes southeastern San LuisObispo County, northeastern Santa Barbara Countyand relatively small portions of Ventura and KernCounties. Major tributaries to the Cuyama Riverare Huasna River and Alamos Creek. On the north,the Cuyama River basin is flanked by the dry,semibarren Caliente Mountains, which attain a maxi-mum elevation of 5,095 feet (U.S. Bureau of Rec-lamation, 1951). The rugged, chaparral-coveredSierra Madre Mountains form the southern bound-ary of the Cuyama River basin and reach an eleva-tion of 5,880 feet. Since February 1959, flow inthe Cuyama River has been regulated by TwitchellReservoir, which retards a portion of interceptedstorm flow for later release. Below the dam, theCuyama River meanders approximately five milesthrough vineyard farmland in a valley less than amile wide surrounded on both sides by hills thatrise quickly to elevations of 800 feet. About a halfmile before Fugler Point the river enters the flat-tened terrain of the Santa Maria Valley.

The Cuyama River with its two principal tributar-ies, Huasna River and Alamos Creek, is the largestcontributor of silt and floodwater to the Santa Maria

River system. The major sediment sources are thesemibarren badlands at the head of the drainageand the channel banks in the Cuyama Valley. TheCuyama River has cut a deep channel in the lowerhalf of the Cuyama Valley. Enough material is avail-able in the steep banks to load any flow of the river.The semidesert area, about two-fifths of the water-shed, has very scant cover, consequently rainfall ineven small amounts produces debris (U.S. Depart-ment of Agriculture, Forest Service, 1951).


The Cuyama River is characterized as “flashy” withrelatively rapid response to rainfall and little or noflow in its reaches during the summer months. Theannual mean flow is approximately 27.8 cfs, how-ever during the 1998 floods flow rates reached26,200 cfs. Due to the variation of flow in theriver, no significant surface water diversions fromthe Cuyama occur. Water quality is variable, rang-ing from 800 to 1000 mg/L TDS depending on whichtributary is contributing the majority of the flow tothe river. In addition the Cuyama River carriessignificant volumes of silt during high flow. Due tocoarse alluvial deposits and low annual precipita-tion in the eastern Cuyama watershed, during yearsof low to moderate precipitation, most of the run-off percolates into the ground before reaching theTwitchell Reservoir. Only in years of high precipi-tation is there a significant contribution to Twitchellfrom the eastern Cuyama River. In years of aver-age rainfall, most of the runoff is from the Huasnaand Alamo watersheds directly north of TwitchellReservoir.

Cuyama River flowing intoTwitchell Reservoir

Water Use:

Twitchell Dam was constructed in 1959 north ofFugler Point on the Cuyama River. It is both aflood control and water conservation reservoir. Waterconserved in Twitchell is released to the Santa MariaRiver during dry months for the purpose of re-charging the groundwater basin. No water is di-verted directly from the reservoir for any other uses.Inflow into Twitchell Reservoir from the CuyamaRiver averages 41,000 AFY.

The Cuyama Valley is a sparsely populated area withsmall urban areas and mainly agricultural land use.Irrigation began in the Cuyama Valley around 1938.Initially, irrigated crops were chiefly potatoes andalfalfa, but a potato rust caused the phasing out ofpotato planting. More recent crops include pista-chios, apples, carrots, and alfalfa.

Santa Maria River


The Santa Maria River is formed by the confluenceof the Cuyama and Sisquoc Rivers at Fugler Point, alocation 20 miles inland from the Coast. The SantaMaria River Valley covers the 260 square mile wa-tershed area downstream of the Cuyama-Sisquoc

River confluence. Much of the valley consists of abroad alluvial area known as the Santa Maria Plain.A broad syncline underlies this plain. Anticlinesare expressed as adjacent highlands and moun-tains. The Sierra Madre Mountains and the Solomonand Casmalia Hills are representatives of the lattertopography, and respectively form the northeast andthe southwest boundaries of the valley basin. Rela-tively elevated terrace surfaces and dune sands bor-der the Santa Maria Plain on the north and south.These deposits comprise the Nipomo Mesa, whichrises gently northward to the western extension ofthe Sierra Madre Mountains, and the Orcutt Up-land, which rises southward to the Solomon andCasmalia Hills.

The Santa Maria River is bounded on the north bya levee that starts at Nipomo Mesa and ends at High-way 1 near Guadalupe. There is also a levee on thesouth that begins at Fugler Point and continues upto the Highway 1 crossing, just north of Guadalupe.

The Santa Maria River historically has possessedtwo outlets to the ocean through sand dune depos-its in the westerly extreme of the basin. The activeriver channel presently discharges to the coast down-stream of Guadalupe. Flow at Guadalupe is zeroduring much of the year, except for agriculturaltailwater flows, and additional flows may occur inwinter during periods of heavy storm runoff. Anadditional point of discharge, now blocked, oc-curred through Oso Flaco Lake along the northernboundary of the valley. The abandoned channelveers from the active river course about three milesupstream from Guadalupe. It follows the course ofOso Flaco Creek, which presently conveys drainageto Oso Flaco Lake. Oso Flaco Creek does not pos-sess flow adequate to maintain an opening to theocean through the dunes.

A historically inactive channel of the Santa MariaRiver is situated in the southern portion of the SantaMaria Plain. This drainage, known as Green Can-yon, encompasses the area south of Guadalupe fromUS Highway 101 to the mouth of the Santa MariaRiver. This inactive channel generally exhibits char-acteristics typical of the alluvial valley plain. The

Aerial photograph of the mouthof the Santa Maria River

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Measuring Water

Cu. Ft. 1 Cubic Foot (7.48 Gallons)62.37 pounds of water

cfs Cubic Feet per Second(water flow measurement)1 cfs = 26,929 gallons per hour;646,300 gallons per day

HCF Hundred Cubic FeetThis is the measurement used to calculateyour water bill

AF Acre-FootThe amount of water required to coveran acre of land one foot deep — 43,560 cu.ft.or 325,851 gallons.

gpm Gallons per minute (water flow measurement)

western-most portion of Green Canyon serves tocollect runoff from a local drainage of about 17square miles as well as storm inflow from the wa-tershed of Corralitos Canyon and Orcutt Creek. Thelatter two tributaries intersect Green Canyon at lo-cations approximately one and one-third miles southof Guadalupe. These watercourses convey drain-age from watershed areas of about 4½ and 38 squaremiles, respectively. Flows conveyed to Green Can-yon are discharged to the Santa Maria River at alocation slightly more than one mile east of theriver mouth.


The Santa Maria watershed is much larger than theSanta Ynez River watershed, but it receives far lessrainfall. The Santa Maria River is ephemeral, withno surface through flows about 83% of the time.Discharges that occur are highly variable. Histori-cally, the stream meander eroded the banks, strippedfarmland of soil, and undercut portions of the floodcontrol levees downstream from Fugler Point. Thehighest flows in the Santa Maria system have beenaround 30,000 cfs at Fugler Point.

Water Use:

The climate, soil, and topography of the Santa MariaValley contribute to the agricultural nature of theregion. Intensely irrigated agriculture dominatesmuch of the Santa Maria Valley. Groundwaterpumpage for agriculture began in the Santa MariaValley in 1898 with the inception of the sugar beetindustry. Irrigated lands gradually expanded withthe introduction of vegetable farming in the valleyin the 1920s and 1930s. Vegetables were histori-cally rotated with sugar beets, beans, alfalfa, anddry land crops (U.S. Department of Agriculture,Forest Service, 1951). Recent crops include straw-berries, broccoli, various flowers, and alfalfa.

The area around the mouth of the Santa Maria Riverhas been designated as a National Natural Land-mark by the US Secretary of the Interior because ofthe presence of extensive sand dunes, dune up-lands, lakes and wetlands (Santa Barbara CountyWater Agency and URS Greiner Woodward Clyde

Consultants, 2000). In addition to oil develop-ment activities and agricultural activities, the coastalarea is a popular recreation destination. There ispublic access at Oso Flaco Lake Natural Area and atRancho Guadalupe Dunes County Park just southof the Guadalupe oil field.

For More InformationJones & Stokes Associates, Inc. and Leeds, Hill &Jewett, Inc. 1979. Final Environmental & WaterResources Reconnaissance Study for State Wa-ter Project and Alternatives. Santa Barbara CountyWater Agency.

Santa Barbara County Water Agency and URS GreinerWoodward Clyde Consultants. 2000. Twitchell Res-ervoir Sediment Management Plan. Santa MariaValley Water Conservation District.

U.S. Bureau of Reclamation. 1951. Santa MariaProject, South Pacific Basin, California.

U.S. Department of Agriculture, Forest Service. 1951.Report of Survey - Santa Maria River Watershed,California: For Runoff and Waterflow Retarda-tion and Soil Erosion Prevention.

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Bradbury Dam and LakeCachuma from Vista Point

Reservoirs

Santa Ynez River Watershed

The Santa Ynez River Watershed extends from the south slope of the San Rafael Mountain Range to the northslope of the Santa Ynez Mountains, and westward from the Ventura County line to the Pacific Ocean. Thethree reservoirs that have been constructed on the Santa Ynez River supply most of the water used in theSouth Coast area of Santa Barbara County. The largest of these is Lake Cachuma, followed by Gibraltar andJameson Reservoirs, which are located upstream.

The United States Bureau of Reclamation (USBR)constructed Lake Cachuma and Bradbury Dam inthe early 1950s as part of the Cachuma Project.The construction of Bradbury Dam began in Au-gust of 1950 and was completed on June 17, 1953.Filling of the reservoir was completed in 1958.

The principal features of the Cachuma Project areBradbury Dam, Lake Cachuma, Tecolote Tunnel,the South Coast Conduit and distribution systems.Included in the main conduit system are four regu-lating reservoirs and the Sheffield Tunnel.

Tecolote Tunnel was one of the most difficult tun-nel projects undertaken by the USBR. The tunnelwas completed in 1956 following a difficult sixyear construction period. Tunnel construction washampered by groundwater inflow reaching 9,000gallons per minute, temperatures up to 117°F, anddangerous levels of methane gas.

Lake Cachuma and Bradbury Dam

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Gibraltar Damand Reservoir

The City of Santa Barbara completed constructionof Mission Tunnel in 1912 and Gibraltar Dam in1920, and thus accomplished the first diversion ofwater from the Santa Ynez River Basin to the SouthCoast area. Mission Tunnel, about 3.7 miles in length,was designed to intercept groundwater flow and tolater convey water from Gibraltar Reservoir to theCity of Santa Barbara. Infiltration into Mission Tunnelvaries with rainfall, but averages approximately 1,100AFY. Gibraltar Dam construction began in 1914and was completed in 1920. During the construc-tion of the dam and reservoir, the City’s water sup-ply became so deficient that residents had to revertto the use of well water, and even that use wasrestricted.

In the winter of 1920-21, the first rainy seasonafter the completion of the dam, the reservoirfailed to fill because the rainfall was below aver-

age. In the 1921-22 season, with rainfall only slightlyabove average, the reservoir filled to capacity, anda large volume went over the spillway, causing ex-tensive damage.

By 1945, sedimentation had reduced storage inGibraltar Reservoir from 14,500 AF to approximately7,800 AF. In 1948, the dam was raised 23 feetand storage capacity was restored to approximatelythe original volume. However, sedimentation hascontinued to decrease the storage capacity of thereservoir by an average of 150 AFY.

Gibraltar Dam

The Montecito Water District completed construc-tion of Juncal Dam and Jameson Lake in 1930.Water is diverted to the Montecito area through theDoulton Tunnel. Construction of Doulton Tunnelbegan in 1924 and initially penetrated only the

Juncal Dam and Jameson Lake

first mile of the Santa Ynez Mountains due to sub-stantial groundwater inflow. The tunnel was finallycompleted in 1928. Groundwater inflow to DoultonTunnel currently averages approximately 440 AFY.

Jameson Lake, muddied bystorm runoff

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Twitchell Reservoir

The United States Bureau of Reclamation constructedthe Vaquero Dam and Reservoir in the late 1950sas part of the Santa Maria Project. The Project pro-vides recharge to the groundwater basin underly-ing the Santa Maria Valley and provides for floodprotection. The project was completed in 1959 ata cost of approximately $11 million dollars, whichwas 30% less than the original estimate. The namewas eventually changed to Twitchell Dam and Res-ervoir to honor Mr. T.A. Twitchell of Santa Maria,who was instrumental in bringing about the project.Twitchell Reservoir is operated and maintained bythe Santa Maria Valley Water Conservation District.

Twitchell Reservoir is important to both the watersupply and the flood protection of the Santa MariaValley. The reservoir supplies about 20,000 AF ofrecharge to the Santa Maria Groundwater Basin an-

Santa Maria River Watershed

The Santa Maria River is formed by the confluence of the Cuyama and Sisquoc Rivers about 20 miles from thePacific Ocean. The Cuyama River Basin, with a drainage area of about 1,140 square miles, drains essentiallyall of the northern half and easternmost portion of the Santa Maria River Basin. Twitchell Dam is located onthe Cuyama River six miles above its junction with the Sisquoc River.

nually. The replacement cost of getting this waterfrom other sources would be millions of dollarsevery year.

Since its completion, Twitchell Reservoir has beentrapping sediments from the 1,140 square mileCuyama River watershed. Original studies estimatedthat 40,000 AF of sediment would accumulate inthe reservoir during the first one hundred years ofoperation. In 1981, a study found that the rate ofsedimentation was about 70% greater than the origi-nal estimate. As of 1998, the accumulated sedi-ment had reached an estimated 44,000 AF. Be-cause of this, the SBCWA and the Santa Maria Val-ley Water Conservation District are preparing a sedi-ment management plan. This plan will help to en-sure the continued safe operation of the reservoir’swater release works, and also extend the usable lifeof the reservoir.

Twitchell Reservoir, filled tonear capacity with stormwater

For More InformationCachuma Operations and Maintenance Board(COMB): 3301 Laurel Canyon Road,Santa Barbara, CA 93105, (805) 687-4011

City of Santa Barbara:http://www.ci.santa-barbara.ca.us/departments/public_works/water_resources/

Montecito Water District: http://www.montecitowater.com/

Goleta Water District: http://www.goletawater.com/

USBR: http://www.usbr.gov/

Trapped or accumulatedsediment surrounding the

intake structure in the dry bedof Twitchell Reservoir

County Reservoir Information

Bradbury Dam Gibraltar Dam Juncal Dam Twitchell Dam

Type of Dam Earth and rock fill Constant radius Concrete arch Earth and rock fillconcrete arch

Structural Height 275 feet 175 feet 160 feet 241 feet

Height Above 205 feet 150 feet N/A 218 feetStreambed

Crest Length 2,975 feet 600 feet 1,407 feet 1,804 feet

Reservoir Area 3,108 acres 244 acres (1998) 138 acres 3.600 acres

Recent Capacity 190,409 AF (1990) 7,264 AF (1998) 5,291 AF (1998) 198,339 (2000)

Drainage Area 417 sq. mi. 216 sq. mi. 14 sq. mi. 1,135 sq. mi.Above Dam

Tunnel Name Tecolote Tunnel Mission Tunnel Doulton Tunnel N/A

Tunnel Length 6.4 miles 3.7 miles 2.2 miles N/A

Tunnel Diameter 7 feet 4 feet to 20 feet 7 feet N/A

Tunnel Slope 3”/1,000 feet NR .0018”/1,000 feet N/A

Tunnel Capacity 100 cfs 40 cfs N/A N/A

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State Water ProjectHistoryHistoryHistoryHistoryHistory

The State Water Project (SWP), managed by theDepartment of Water Resources (DWR), is the largeststate-built, multipurpose water project in the country.The SWP system collects, stores and distributes waterfrom northern California, where most of the state’srainfall occurs, to southern California, where mostof the state’s population lives. Approximately 20million of California’s 32 million residents receiveat least part of their water from the SWP, and SWPwater is used to irrigate approximately 600,000acres of farmland.

In 1951, the state legislature authorized construc-tion of the SWP, a water storage and supply systemto capture, store, and redistribute surface runoffon a massive scale. Eight years later, legislation waspassed to provide the mechanism for obtaining fundsnecessary to construct the initial facilities. In 1960,California voters approved a $1.75 billion bondissue to build the SWP. The initial facilities of theSWP were completed in 1972, although some partsof the Project have been delivering water to Cali-fornians since 1962.

Total entitlements to the SWP are approximately4.2 million AFY, while the firm yield (i.e., duringdrought periods) of existing SWP facilities is 2.4million AFY. The average annual yield of the projectapproaches 3 million AFY. It is projected that fu-ture improvements to the SWP system, both struc-tural and operational, will increase both the firmand average yields.

The State Water Project inSanta Barbara County

In 1963, the Santa Barbara County Flood Controland Water Conservation District contracted with theDWR for the delivery of SWP water. At that time, theCounty began payments to DWR to retain an en-titlement to SWP for 57,700 AFY, but funds werenot allocated to construct the necessary delivery sys-tem. The contract with the DWR was handled by theSBCWA. In 1981, the contract was amended to reducethe County’s State Water entitlement to 45,486 AFY.

In 1979, a bond measure was placed on the ballotto secure funds to construct the delivery system tobring SWP water into the county. Fear of growth,environmental concerns, and opposition to highwater costs caused a majority of voters to vote againstthis measure.

In 1991, after six years of extremely dry condi-tions, voters throughout Santa Barbara County votedto import SWP water. This included the communi-ties of Carpinteria, Summerland, Montecito, SantaBarbara, Hope Ranch, Goleta, Buellton, Solvang, SantaYnez, Orcutt and Guadalupe. The Santa Maria CityCouncil and Vandenberg Air Force Base also decidedto participate in the SWP. The communities of Lompoc,Vandenberg Village, and Mission Hills voted not toparticipate in the SWP.

As a result of numerous favorable bond elections,the Central Coast Water Authority (CCWA) was formedto finance, construct, manage, and operate SantaBarbara County’s 42 mile extension of the SWP waterpipeline and a regional treatment plant to treatSWP water for both San Luis Obispo and Santa Bar-bara Counties. The CCWA is made up of eight mem-ber agencies, one associate member, and four ad-ditional participants. The CCWA is governed by aneight member Board of Directors, with a represen-tative from each member agency.

The following table presents the allocated entitle-ment of SWP water to each project participant. Ex-isting entitlements range from 50 AFY (Raytheon

Construction of the State WaterProject Pipeline in Santa Barbara

County began in 1994

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Systems Company) to as high as 16,200 AFY (Cityof Santa Maria), though actual water deliveries maybe less than the entitlement in any given year de-pending on a number of factors, primarily cus-tomer demand and weather in northern California.Factors other than drought that may cause short-term delivery reductions of SWP water include equip-ment failure and natural disasters such as floodsand earthquakes. Other factors that affect the long-term reliability of the State Water Project includetiming of additional SWP storage facility develop-ment, ongoing environmental challenges to the SWP,and eventual utilization of full SWP entitlement byother SWP water contractors.

Construction of the facilities to import SWP waterto the county began in 1994, including pipelines,pumping plants and treatment costing almost $600million. The Coastal Branch portion of the project

brings water 117 miles from the California Aque-duct in Kern County, through San Luis Obispo Countyand the Santa Maria Valley, and continuing to thenortherly portion of Vandenberg AFB. The DWRfinanced this section of the pipeline and constructedit with the CCWA’s assistance.

At Vandenberg AFB, the Coastal Branch connectsto the 42-mile pipeline comprising the Mission Hillsand the Santa Ynez Extensions. The Santa Ynez sec-tion, which was financed and constructed by theCCWA, ends at Lake Cachuma. Water is then deliv-ered through existing facilities to the south coastof Santa Barbara County. The CCWA also constructedand operates the Polonio Pass Water Treatment Plant,located in northern San Luis Obispo County. In ad-dition, under a joint powers agreement with the DWR,the CCWA operates all of the Coastal Branch facilitiesdownstream of the treatment plant.

State Water Entitlements in Santa Barbara County

Project Participant SWP Allocation 1999 Delivery (AFY)

California Cities Water Co. (Orcutt area) ................................................................. 500 ........................................ 215Carpinteria Valley Water District ..................................................................................... 2,000 ........................................ 00*

(Includes Summerland)City of Buellton ........................................................................................................................................ 578 ........................................ 583City of Guadalupe .................................................................................................................................. 550 ........................................ 484City of Santa Barbara ................................................................................................................... 3,000 ............................................... 0City of Santa Maria ...................................................................................................................... 16,200 ............................... 11,380Goleta Water District .................................................................................................................... 4,500 .............................. 32*(+)La Cumbre Mutual Water Co. .............................................................................................. 1,000 ........................................ 366Montecito Water District .......................................................................................................... 3,000 ........................................ 51*Morehart Land Company ............................................................................................................... 200 ............................................... 1Raytheon Systems Company ........................................................................................................... 50 ............................................ 55Santa Ynez River WCD, I.D. #1 (Includes City of Solvang) .......... 2,000 ................................. 3505*Vandenberg Air Force Base ................................................................................................... 5,500 .................................. 3,438

TOTAL 39,078 23,853Drought buffer** 3,908

* Note: Santa Ynez River WCD, I.D. #1 exchanged 2,989 AF of their delivery. Exchange recipients were Goleta (2,444 AF),Montecito (99 AF) and Carpinteria (446 AF)**The drought buffer entitlement of 3,908 AFY increases the reliability of each project participant’s entitlement. This entitlementcan be stored for future use and/or requested in dry years when cutbacks are expected to SWP allocations. By storing this waterand/or increasing the CCWA’s water request in dry years, even after a percentage cutback by the DWR, the CCWA projectparticipants will reduce shortages in their entitlement deliveries.+ Goleta Water District has an additional 2,500 AF drought buffer.

Unit CostUnit CostUnit CostUnit CostUnit Cost

The cost per AF for SWP water varies depending onthe location of each project participant along thepipeline. All participants pay their share of the costsfor the water treatment plant located at PolonioPass based on (1) SWP water entitlement for capi-tal and fixed operating costs and (2) entitlementdeliveries for variable costs. Each participant alsopays for its share of the Coastal Branch and CCWAExtension fixed and variable costs essentially to thepoint where it takes delivery of water. Therefore,costs for participants in the northern part of thecounty are less than for those on the South Coast.

The unit cost of SWP water ranges from about $900per AF in Santa Maria to about $1,500 per AF inthe Santa Ynez Valley and South Coast of Santa Bar-bara County. The unit cost differs for each projectparticipant for a number of reasons including, butnot limited to: (1) location along the pipeline (e.g.,participants that are located in the north county donot share in the cost of facilities downstream oftheir turnouts), (2) financing of the CCWA projectfacilities (certain participants paid cash for theirshare of the CCWA facilities instead of financingthem through the CCWA revenue bond issue), (3)financing of local project facilities using the CCWArevenue bond funds, and (4) capitalizing revenuebond interest during the first three to six years ofthe bond issue.

EnvironmentalEffects and MitigaEffects and MitigaEffects and MitigaEffects and MitigaEffects and Mitigationtiontiontiontion

Environmental Impact Reports (EIRs) were com-pleted prior to constructing each segment of thepipeline and associated facilities. These reportsdocumented potential environmental impacts of theproject and identified ways to lessen or avoid thoseimpacts. Identified mitigation methods includedusing existing facilities and avoiding new construc-tion where possible, and locating the pipeline awayfrom environmentally sensitive areas. Changes inthe pipeline’s location were made to protect sensi-tive habitats, animal species and cultural resources.

Where it was necessary to remove sensitive nativevegetation such as oak trees and Burton Mesa Chap-arral, replacement trees and chaparral were plantedalong the pipeline right-of-way and in other “offsite”areas. During construction of the project, environ-mental experts were hired to observe and monitorconstruction activity, and to assist construction teamsin avoiding or mitigating impacts to wildlife, bio-logical and cultural resources.

ReliabilityReliabilityReliabilityReliabilityReliability

The SWP, as with many other sources of water, isnot 100% reliable. This is particularly true duringdroughts or when operational problems occur withinthe SWP system. Another major factor affecting thereliability of SWP water is the fact that the SWP isnot complete. The total complement of facilitiesneeded for the SWP to deliver all of its entitlementsis not yet constructed. This is, of course, the sub-ject of much discussion and planning among engi-neers and planners for the SWP and SWP watercontractors. In the meantime, when shortages oc-cur along the system, all contractors must take aproportionate reduction in their entitlement deliv-eries during the shortage.

The Sacramento-San Joaquin Delta is part of thesystem that supplies water to SWP water contrac-tors south of the Delta. Since 1995, a group ofstate and federal resource agencies known as CALFED

State Water ProjectCalifornia Aqueduct bringingNorthern California water to

the Coastal Branch pipeline

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Buellton Lompoc

Santa Ynez River

Santa Barbara

101

Lake Cachuma

GibraltarReservoir

JamesonLake

Santa Maria

has been developing an unprecedented program torestore the Delta’s ecosystem and reliability as awater source. In the summer of 1996, after anexhaustive year-long public process, CALFED’s Bay-Delta Program identified three alternative solutionsthat involve different Delta water conveyance facili-ties and varying levels and locations of water stor-age. Formal environmental review of these alter-natives is ongoing.

Each conveyance system would have an optimalamount of storage to meet overall CALFED goals ofan improved ecosystem, improved water quality andmore reliable supplies. Implementation of the se-lected alternative will enhance the reliability of SWPwater supplies and reduce shortage reductions.

Benefits

State Water Project water helps:

• Reduce the overdraft in all major ground-water basins in the county except the CuyamaBasin, which does not have a water purveyorthat receives SWP water;

• Improve water quality in areas that directlyreceive SWP water (i.e., participants fromSan Luis Obispo County in the north andSanta Ynez in the south);

• Increase overall water supply in Santa Bar-bara County.

For More InformationCalifornia Department of Water Resources, 1999.California State Water Project Atlas.

Central Coast Water Authority: (805) 688-2292 orCCWA’s web site: http://www.ccwa.com/

Cuyama River

San Luis ObispoCounty

Santa BarbaraCounty

Interstate 5

California Aqueduct

TwitchellReservoir

1

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State Water Project Pipeline in Santa Barbara County

Desalinationround horizontal media filters. There are two setsof filters — primary, consisting of sand, gravel,and anthracite, and secondary consisting of thesame media as primary, plus garnet. Next, the car-tridge filters act as a check to catch any materialthat gets through the primary and secondary stages.At this point all particulate matter has been re-moved from the water; only dissolved salt remains.Then, pumps drive the water at 800 pounds persquare inch (p.s.i.) through reverse osmosis mem-branes that separate the dissolved salt from the wa-ter. Approximately 45% of the pressurized seawa-ter goes through membranes and becomes drink-ing water. The drinking water is pumped into theexisting Yanonali Street water main for distribu-tion to water customers. The remaining seawaterand concentrated salts (brine) are combined withtreated wastewater from the adjacent wastewatertreatment plant, and discharged to the ocean at theend of the 1.5 mile long outfall line.

Electricity is used to operated the facility. At thisfacility, it takes approximately 6,600 kilowatt hoursof electrical energy to produce one acre-foot (AF)(326,000 gallons) of desalted water. (This is ap-proximately the amount of energy one family usesin a year.)

History

The 1986-1991 drought showed that the City ofSanta Barbara’s pre-drought water supplies wereinadequate. In 1990-91, an extensive analysis wasdone to determine which water supply alternativeswould best ensure adequate water supplies for thefuture. The analysis showed that either desalina-tion alone, at a capacity of 5,000 acre-foot peryear (AFY), or the State Water Project at an entitle-ment of 3,000 AFY plus a desalination capacity of3,000 AFY as a drought backup, were the best al-ternatives. In June 1991, City voters supportedboth the State Water Project and desalination aspermanent water supplies and the City has includedthe combined State Water Project/desalination op-tion in its Long-Term Water Supply Program(LTWSP).

The DesalinationProcess

Desalination is the process of removing salt fromseawater. Desalination is used in many arid coun-tries around the world to provide a reliable sourceof drinking water. The process dates back to the4th century B.C. when Greek sailors used an evapo-rative process to desalinate seawater. Most UnitedStates desalination plants are used to clean brack-ish groundwater or to produce highly purified wa-ter for industrial use. Desalination separates sa-line water into two products: fresh water and watercontaining the concentrated salts, or brine. Suchseparation can be accomplished by a number ofprocesses. The three most common processes aredistillation, electrodialysis, and reverse osmosis.Distillation works by heating salty water to producewater vapor that is then condensed to form freshwater. Both the electrodialysis and the reverse os-mosis processes use membranes to separate saltsfrom water.

The City of Santa Barbara Charles Meyer Desalina-tion Facility, located at 525 E. Yanonali Street, wasbuilt in 1991-1992 as a temporary emergency wa-ter supply in response to the severe drought of 1986-1991. The facility is the largest seawater reverseosmosis desalination facility in the United States.First, ocean water is pumped at a very low pressurethrough a 2,500 foot seawater intake line to thefacility. The incoming seawater is pretreated in

Filtered seawater is pumpedthrough a reverse osmosis

membrane that separates thesalt from the seawater, expelling

drinking water through onepipe and brine through another

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The Charles Meyer DesalinationFacility serves the City ofSanta Barbara

As a result of the analysis in the LTWSP and the1991 vote, the Santa Barbara City Council decidedthat the temporary facility would be converted topermanent status for use as a backup during futuredroughts. The facility also has the potential for useduring non-drought periods, which would help meetregional or statewide needs for water by operatingunder a water exchange agreement.

To obtain permanent status the facility went throughadditional environmental review and permittingwhich was completed in December 1995. The fa-cility was dedicated as the Charles Meyer Desalina-tion Facility on December 11, 1995 in honor of Mr.Meyer’s long and dedicated service on the CityWater Commission, and in recognition of thefacility’s permanent role in the City’s water future.

The City’s facility was built by a private company,Ionics, Inc., under a “take or pay” contract. Overthe 5-year contract period, the City, along with theMontecito and Goleta Water Districts, paid off the$34 million construction cost and either paid forwater produced or paid to maintain the facility instandby mode. Due to abundant rainfall since 1991the facility has been on standby since the initialtesting period was completed in June 1992. Thefacility has permits to operate as a permanent partof the City’s water supply and all equipment is com-patible with long-term use.

Unit Cost

Because a relatively high proportion of the cost ofdesalination is in operation rather than capital costs,savings accrue when the water is not needed. Thismeans that desalination will be as cost effective asother new water supplies, such as State Water, forwhich costs remain relatively constant regardlessof the amount of water delivered. The cost of de-salted water is approximately $1,100 per AF in-cluding labor, chemicals, power, maintenance, anda sinking fund to replace worn components.

There are several other desalination facilities lo-cated in coastal communities throughout the state.These include Catalina Island and the City of MorroBay. For communities in semiarid climates, de-salinated ocean water provides a water source thatis not dependent on rainfall. This gives the com-munity the ability to provide fresh water as a backupfor depleted surface water supplies, thereby easingthe hardship of drought. As technology advancesand other water sources become less available,desalination will become more cost-effective andmore communities may turn to this as a viable sourceof water.

For More Information

Aston, D. 1999. Water of Santa Barbara County.Santa Barbara County Water Agency.

American Desalting Association:http://www.webcom.com/ada/

City of Santa Barbara:http://www.ci.santa-barbara.ca.us/departments/

public_works/water_resources/

USBR: http://www.usbr.gov/water/desal.html/

Water QualityInfluencing Factors

Water Treatment

Influencing FactorsGeneral Information

Water quality is a term used to describe the chemi-cal, physical, and biological characteristics of wa-ter with respect to its suitability for a particularuse. Water quality standards have been developedthrough nearly a century of trial and error and ad-vances in technology. Currently, both state and fed-eral standards regulate the quality of water that isprovided to users. The importance of water qualityas it relates to human activity is directly related tothe intended use(s) of the water. The highest qual-ity standards apply to drinking water, while some-what lower standards apply to water used for irriga-tion or recreation. The California Department ofHealth Services’ (DHS) drinking water standards provideone example of how water quality can be evaluated.

Extensive laboratory testsensure that local water qualitymeets state and federalstandards

California DHS has set Maximum Contaminant Lev-els (MCLs), which are enforceable, regulatory lev-els under the Safe Drinking Water Act that must bemet by all public drinking water systems to whichthey apply. Primary MCLs are established for a num-ber of chemical and radioactive contaminants, whileSecondary MCLs are set for taste, odor, or appear-ance of drinking water. Action Levels (ALs) arehealth-based advisory levels established by DHS forchemicals for which primary MCLs have not beenadopted. They are not enforceable standards, butexceedances do prompt requirements for localgovernment notification, recommendations for con-sumer notice and, at higher levels, recommenda-tions for source removal. In addition, there are anumber of unregulated chemicals that are or maybe required to be monitored, depending on thevulnerability of drinking water sources.

Water quality varies from source to source and isinfluenced by natural and human factors. Naturalinfluences include the layers of rock and soil sur-rounding an aquifer or surface conveyance, whichdetermine the types and amount of minerals foundin surface water or groundwater. Human impactson water quality result from such activities as urban-ization (storm-water runoff and septic tanks), agri-cultural irrigation (runoff from irrigated land), di-rect disposal of wastewater into waterways, and graz-ing of livestock.

The origin of water pollution is generally character-ized as either being from nonpoint (diffuse) or pointsources. Nonpoint source pollution is caused by rain-fall or snowmelt moving over and through the groundpicking up and carrying natural and human-madepollutants, and depositing them into lakes, rivers,coastal waters, and underground sources of drinkingwater. Point source pollution comes from sourcesthat are concentrated and readily identifiable likedischarges from wastewater treatment facilities, solidwaste landfills, golf courses, stockyards, poultry farms,and feedlots. Point sources of pollution are moreeasily controlled and monitored so they have beenthe focus of most pollution reduction efforts to date.Only recently has the control of nonpoint sources

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Contaminants

Water quality comparisons in this report will focuson Total Dissolved Solids (TDS), chloride, and ni-trates. The DHS secondary standard for total dis-solved solids (TDS) in drinking water is 1,000 mil-ligrams per liter (mg/L) and the secondary stan-dard for chloride in drinking water is 250 mg/L. TheDHS primary standard for nitrates in public drinkingwater systems is 45 mg/L (State of California, 1995).

Chloride contamination is a concern in Santa Bar-bara County due to a variety of factors. The mostprevalent potential source of chloride contamina-tion in the county is from seawater intrusion. El-evated chloride levels associated with seawater in-trusion occur when there are no geological barri-ers (impermeable bedrock or clay layers) betweencoastal groundwater basins and the basins underthe ocean that are saturated with seawater. The like-lihood of seawater intrusion is increased when ex-tensive pumping of groundwater basins adjacent tothe ocean affects groundwater flow gradients andseawater is drawn inland. Irrigated agriculture alsoincreases chloride levels in groundwater by intro-ducing problems of poor drainage and increasingevaporation.

Nitrates can accumulate in watersheds due to theuse of fertilizers or the presence of poorly main-tained septic systems. Nitrogen not taken up byplants can leach through the soil to groundwaterand then flow to recharge areas or private wells.Nitrates are of particular concern in drinking wa-ter sources because nitrates interfere with the ab-sorption of oxygen into the bloodstream. AlthoughSanta Barbara County has extensive agricultural areasand many residents use septic systems, nitrate con-tamination of groundwater supplies is rare.

High levels of total dissolved solids frequently im-pair the use of groundwater in California. In SantaBarbara County, several groundwater basins showdegradation of water quality due to high TDS lev-els. Total dissolved solids may be increased through

natural dissolution of soluble materials, reductionin recharge from surface waters, and constant cy-cling and evaporation of irrigation water.

Local Conditions

Surface and groundwater quality in Santa BarbaraCounty is variable but generally of high enoughquality for reasonable use. As described above,quality is determined by factors such as native con-dition of groundwater and surface water, sourcesof contamination (natural and human induced)and presence of seawater. Several areas in the county(Santa Barbara and near Santa Maria) have experi-enced signs of seawater intrusion. As of yet, theseinitial signs of intrusion do not pose a threat todrinking water supplies. Nitrate contamination hasbeen found in some portions of the Santa MariaGroundwater Basin. The Regional Water QualityControl Board has identified this problem and plansto implement a research effort to isolate the causesand seek solutions. Increases in total dissolvedsolids have also been recorded in many basins withinthe county. Efforts to increase recharge and im-prove irrigation efficiency have been implementedto address this problem.

Groundwater Quality: The USGS has performedwater quality testing in most of the fourteen ground-water basins in Santa Barbara County. An extensivestudy of the Lompoc area was conducted in re-sponse to increasing groundwater demands and his-toric documentation of the deterioration of waterquality in some parts of the Lompoc GroundwaterBasin (Bright et al., 1992). For summaries ofwater quality information on specific groundwaterbasins, please refer to the Groundwater section.

Surface Water Quality: Two sources of surfacewater include local reservoirs/rivers, and water fromthe State Water Project (SWP). The highest qualitywater in the county is State Water Project water,which ranges from 222 to 510 mg/L TDS. In por-tions of the county where SWP water is distributeddirectly to customers, the water is of very high quality.

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Water TreatmentGeneral Information

Portions of the following information have beenadapted from: The City of Santa Barbara Waterand Wastewater Systems Inventory (1998) andthe City of Lompoc Urban Water ManagementPlan 1995 - 2000 (1995).

Surface water acquires its characteristics (taste, odor,chemical and mineral make up, temperature, cor-rosiveness, and clarity) from the environment with

which it has contact. Thus surface water qualityvaries by location and season. During the late summerand early fall, surface water deteriorates slightly inquality because of the growth of algae. Water takenfrom surface water supplies may contain variouscontaminants. Possible contaminants include siltsand clays, dissolved minerals and salts, organic mate-rial from vegetation and wildlife, algae, bacteria, pro-tozoans, viruses and man-made pollutants. In orderto remove these contaminants and to comply with stateand federal water quality standards, water is treatedbefore it is distributed for consumption.

In many areas of the county, SWP water is blendedwith other, lower quality water, which results in ahigher overall quality of the water distributed tocustomers. For the South Coast water purveyors,SWP water is conveyed through Lake Cachuma whereit mixes with local surface water. The water is thendirected to local water treatment plants, after whichit is distributed to customers.

According to the USGS figures for 1998 (Agajanianet al., 1998) the TDS for the rivers in Santa Bar-bara County range from 518 mg/L to 1,130 mg/L(see below). Water quality sampling was completedin October, April and May of the 1998 Water Year.Some of the variations in water quality seen alongthe Santa Ynez River are a partial result of the addi-tion of SWP water mentioned above.

Total Dissolved Solids in Local Rivers - 1998

Cuyama River ..................................... 1,130 mg/LSanta Maria River ......................... 1,030 mg/LSisquoc River ..................................... 862 mg/LSanta Ynez River

at Jameson Lake ................. 842 mg/Lat Lake Cachuma ............... 518 mg/Lbelow Lake Cachuma .... 625 mg/L

(Source: Agajanian et al., 1998)

The Health and Safety Code of California State Lawplays a role in maintaining surface water quality

throughout California by preventing bodily contactof water that serves as drinking water supply. Sec-tions 115825 (a) and (b) prevent bodily contactwith water in Lake Cachuma:

(a) It is hereby declared to be the policy of thisstate that multiple use should be made of all pub-lic water within the state, to the extent that mul-tiple use is consistent with public health and pub-lic safety. (b) Except as provided in Sections 115840,115840.5, and 115841, recreational uses shall not,with respect to a reservoir in which water is storedfor domestic use, include recreation in which thereis bodily contact with the water by any participant.

For More InformationCarpenter, A.G.; King, N.J. and Montoya, I. 1994.Water Quality Control Plan: Central Coast Region- Region 3. State of California, Regional WaterQuality Control Board - Central Coast Region.

Environmental Protection Agency; Water Quality -Surf Your Watershed:http://www.epa.gov/surf/surf_search.html/

State of California, The Resources Agency, Depart-ment of Water Resources, Division of Local Assis-tance. 1995. Quality Assurance Technical Docu-ment 3: Compilation of Federal and State Drink-ing Water Standards and Criteria.

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Communities in Santa Barbara County rely on dif-ferent types of water supplies. As a result, there is awide variety of treatment processes in use. The fol-lowing information provides a description of thetreatment processes used in four communities withinthe county and in the State Water Project.

City of Santa BarbaraCity of Santa BarbaraCity of Santa BarbaraCity of Santa BarbaraCity of Santa Barbara

William B. Cater Water Treatment Plant

The City of Santa Barbara constructed the WilliamB. Cater Filtration Plant in 1964. The plant wasoriginally designed as a lime softening plant with atreatment capacity of 10 million gallons per day.The capacity was increased in 1969 to 16 milliongallons per day by converting sand filters to dualmedia (sand and anthracite coal) filters. The “JointExercise of Powers Agreement” to expand and op-erate the Cater Filtration Plant to treat all Cachumawater delivered to the districts was signed in 1978and is still in effect for the Montecito Water Dis-trict, the Carpinteria Valley Water District and theCity of Santa Barbara. The plant was expanded from16 million gallons per day to the current 37 mil-

lion gallons per day capacity in 1982. The in-crease in capacity was the result of the addition offive filters. The water treated at the plant may bedrawn directly from the South Coast Conduit (SCC)or from Lauro Reservoir. The water in the SCCcomes directly from Lake Cachuma (via the TecoloteTunnel). The water in Lauro Reservoir is a combi-nation of water from Gibraltar Reservoir (via theMission Tunnel into the Penstock pipeline) andwater from the SCC. Normal operation is for Caterto draw the water from Lauro Reservoir.

The Cater Treatment Plant method of treatment isconsidered “conventional treatment” using the pre-treatment, aeration, flash mix, coagulation/floc-culation, sedimentation, filtration and disinfectionprocess. The water treated at this facility is testedextensively to ensure compliance with state and fed-eral water quality standards. The Plant is locatedat 1150 San Roque Road and is staffed 24 hours aday. The facility is open to the public and tours areoffered. For more information contact the City ofSanta Barbara at (805) 897-2609.

Water Treatment PlWater Treatment PlWater Treatment PlWater Treatment PlWater Treatment Plants inSanta Barbara Countybara Countybara Countybara Countybara County

Lauro Reservoir and the CaterWater Treatment Plant

The quality of groundwater is determined by thecharacter of the water entering a groundwater ba-sin, the chemical nature of the groundwater basin,and the time of residence within the basin. Waterquality may vary within the same groundwater ba-sin depending on where the well is located withinthe basin and the depth from which the well draws.Generally, water taken from groundwater supplieswas naturally filtered as it passed through the lay-ers of the earth so, unless the basin is contami-nated, it usually does not require the same level oftreatment as water from surface supplies. However,groundwater may also require some treatment inorder to meet water quality standards.

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Pretreatment

Pretreatment is used to kill disease-causingorganisms and help control taste and odorcausing substances. A pretreatment chemicalcould be any number of oxidants or disinfec-tants. Ozone, hydrogen peroxide, potassiumpermanganate and chlorine are all commonlyused in water treatment.

Aeration

The purpose of this process is to “off-gas”taste and odor causing substances by passinglarge quantities of air through the water. Thisis accomplished by pumping air through aseries of diffusers placed on the bottom ofthe storage basins, which causes the water to“boil”. The resulting air bubbles carry offthe most volatile of the taste- and odor-caus-ing organics.

Flash Mixing

The flash mix, or rapid mix process, occursjust after coagulation chemicals are added tothe raw water. Coagulation chemicals are usedto attract particles together that will not readilysettle or filter out of the water. Some ex-amples of coagulation chemicals include alu-minum sulfate and various polymers.

Coagulation/Flocculation

Coagulation starts immediately after flash mix-ing and is facilitated by the flocculation pro-cess. Flocculation is a gentle mixing of co-agulated raw water. This mixing allows par-ticles now “sticky” from the addition of co-agulant, to gather to form larger, heavier par-ticles called “floc”.

Sedimentation

The sedimentation process settles out largersuspended particles and the floc created throughthe coagulation/flocculation process. As theraw water flows very slowly through the sedi-mentation basin, heavy particles fall to thefloor while the water overflows the basin andis channeled into filters. The particles rest-ing on the floor of the basin are moved into asludge basin for eventual disposal.

Filtration

Through the filtration process, any remain-ing particles are removed from the raw water.The water may be filtered through layers ofsand, gravel and/or coal. The raw water trav-els through the various filter materials andout into the treatment plant reservoir. Someexamples of filter materials include mixedmedia (layers of various sizes of gravel, high-density garnet, sand and anthracite coal), di-atomaceous earth, and granular activated car-bon (GAC).

Disinfection

The finished water from the treatment plantmay be disinfected as it leaves the reservoirand enters the distribution system. Disinfec-tion ensures unwanted bacteria and organ-isms have been eliminated and helps discour-age any further growth of disease-causing or-ganisms in the drinking water.

Overview of the Treatment Process

There are many methods of treating water so that it is fit for potable uses. The following informationoutlines several steps that are typically taken to treat water that will be sold for consumption.

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Goleta Water District

Corona del Mar Water Treatment Plant

The Corona del Mar Water Treatment Plant beganoperation in 1974. Due to the plant elevation of192 meters (630 feet), water can move throughthe plant by gravity flow and be delivered withoutpumping to the vast majority of district customers.The design capacity of the plant is one cubic meterper second (about 24 million gallons per day),with a peak capacity of 1.6 cubic meters per sec-ond (about 36 million gallons per day). The “rawwater” received from Lake Cachuma is directed tothe plant for removal of suspended matter, such asclay particles and algae, in order to meet state healthstandards. The stages of treatment completed atthis plant include pretreatment, flash mixing, co-agulation/flocculation, sedimentation, filtration, anddisinfection. These processes are precisely con-trolled and carefully monitored around the clock. Formore information about the plant and treatment pro-cess, call the Goleta Water District at (805) 964-6761.

City of Lompoc

The City of LompocWater Treatment Plant

The City operates eight wells of varying capacitiesbetween 250 and 2,500 gallons per minute. Ground-water is pumped from the wells to the water treat-ment plant for demineralization and softening. Limeand caustic soda are used to reduce the hardnessby approximately 50%. The City of Lompoc WaterTreatment Plant has a peak capacity of 8 milliongallons per day with a reservoir capacity of approxi-mately 7.5 million gallons of usable storage. For moredetailed information about the treatment process, pleasecall the City of Lompoc at (805) 736-1617.

City of Santa Maria

The City of Santa Maria relies mostly on State WaterProject water for its water supplies. This water is

of sufficient quality that it requires little treatmentbeyond addition of chlorine and ammonia (see be-low for information on SWP water treatment). Formore information contact the City of Santa Maria at(805) 928-5022.

State Water Project

Polonio Pass Water Treatment Plant

State Water Project water begins as rain and snowmelt from the Sierra Nevada Mountain Range. Itpasses through both natural streams and rivers andman-made conveyance structures on its way to thePolonio Pass Water Treatment Plant in San LuisObispo County. At this treatment plant, water issent through the flash mixing, coagulation/floccu-lation, sedimentation, filtration and disinfection pro-cesses. For more detailed information on the treat-ment process, please call the Central Coast Water Au-thority at (805) 688-2292.

For More Information

Central Coast Water Authority: http://www.ccwa.com/

City of Santa Barbara:http://www.ci.santa-barbara.ca.us/departments/public_works/water_resources/

Goleta Water District:http://www.goletawater.com/

Polonio Pass WaterTreatment Plant

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