Where Does Your Water Come From?

Water is a vital resource to Santa Barbara County. The availability, quality and cost of water in this area have greatly influenced the economy and the community. Like other areas with limited water supplies, county residents must manage resources carefully and supplement local supplies with water from other regions. County water sources are diverse and the facilities and programs established to manage those supplies are complex. To understand more about the unique hydrology of our county, see a map of average county rainfall and the 2016 Water Year Santa Barbara County Hydrology Report.

Santa Barbara County residents obtain their water from several sources: groundwater withdrawal, storm runoff collected in local reservoirs, the State Water Project, 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 2019. 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. 





2019_guadalupe    2019_lacumbre                         






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. 


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. Locally, groundwater is even more important, making up nearly 75% of the total water used in the county.  

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 Jameson, Gibraltar, 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. 

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.

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. 


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."