Where Does Your Water Come From?   

Santa Barbara County residents obtain their water from several sources: groundwater withdrawal, storm runoff collected in local reservoirs, the State Water Project, desalination, and recycled water. The County's potable water supply is delivered to the public through a variety of water purveyors: incorporated cities, community service districts, water districts, public utility companies, conservation districts and others.

Below are water sources listed alphabetically by area for 2020. These charts are for the water purveyor's water sources and do not necessarily coincide precisely with the geographic area of the same name.  Water sources can vary considerably for some water purveyors from year to year. 



City of Buellton 2021Carp2021

Casmalia2021                Cuyama2021

Golden State Water Co     Goleta2021

Guadalupe2021      LaCumbre2021                       

Lompoc2021         LosAlamos2021        

MissionHills2021 Montecito WD2021

cityofSB2020   CityofSM2020       


VAFB2020   VVCSD2020       



The City of Santa Barbara Charles Meyer Desalination Facility was built in 1991-1992 as a temporary emergency water supply in response to the severe drought of 1986-1991. Designed to filter ocean water in order to generate potable drinking water, the facility is currently in "long-term storage mode" and was brought back online due to the historic drought in 2015. Construction of improvements to the plant were finished in 2017 and the City of Santa Barbara began to service water to customers.  For more information on the of the Charles Meyer Desalination Plant and to book a tour, visit the  City of Santa Barbara's Desalination page. Watch a video with more information about the plant called, " The Supply Nearby."


Groundwater is the water found in the spaces between gravel, sand, silt, and clay in areas where water accumulates to form aquifers. Rain which reaches the earth's surface can permeate the ground and slowly makes its way downward through the soil before reaching an impermeable layer, such as clay or rock. Groundwater use varies greatly by region but makes up about 30% of California's annual water supply in normal years and up to 60% in drought years.


Lake Cachuma

Lake Cachuma is Santa Barbara County's largest reservoir.  It was created by the construction of Bradbury Dam in 1953 and stores flood waters of the Santa Ynez River.  Water is diverted from Lake Cachuma through the Tecolote Tunnel which extends approximately 6.4 miles through the Santa Ynez Mountains. Cachuma is a Federal government (USBR) funded project and is managed by USBR and the Cachuma Operation and Maintenance Board.  What sets Lake Cachuma apart from other local reservoirs is that it is shared by several different agencies.   

View time lapse of  Lake Cachuma levels from 2013 to 2019.

Local Streams and Reservoirs

Surface water found in streams and reservoirs is often a vital component to water supplies for domestic use. Development of reservoirs can reduce the threat of flooding and store stream runoff until it is needed; allowing society to use water from winter rains to meet our needs during the dry summer and fall months when streams cannot meet demand. Locally, the  JamesonGibraltar, and  Cachuma reservoirs on the Santa Ynez River help meet the needs of communities on the South Coast and helps supplement groundwater supplies in the Santa Ynez River downstream.  Twitchell reservoir on the Cuyama River helps reduce threats from floods and replenishes groundwater important to agriculture in the Santa Maria Valley.

Recycled Water

Water recycling (or water reclamation) involves treating municipal wastewater to remove sediments and impurities for reuse. Using recycled water reduces reliance on increasingly scarce and expensive surface water and can minimize groundwater overdraft (extracting more water than is replenished.) Further, recycled water is a local, drought-resistant supply. Currently, the City of Santa Barbara and Goleta Water District distribute recycled water to some parks, schools, and commercial businesses to reduce use of drinking water for landscapes. While not supplying water directly to landscape uses, the City of Santa Maria uses their treated wastewater to help recharge groundwater supplies.

State Water Project

First raised as a concept in 1919, the initial approval of funding in 1960 by California voters for the  State Water Project (SWP) now includes 34 storage facilities and over 700 miles of canals and pipelines. Water is delivered from Northern California rivers through the California Bay-Delta into the San Joaquin Valley, where some water is used for agriculture and the rest is pumped to Southern California. Capable of storing 5.8 million acre-feet of water, the SWP provides water for over 25 million Californians. In 1991, voters in Santa Barbara approved a local extension of the SWP following a multiyear drought, resulting in the Coastal Branch which serves San Luis Obispo and Santa Barbara County. While droughts have caused less than full deliveries of SWP in recent years, the importance of these deliveries on California's economy cannot be underestimated.