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Desalination

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The City's Charles E. Meyer Desalination Plant produces three million gallons of drinking water per day. This is equivalent to 3,125 acre-feet of water annually, or about 30 percent of the City’s demand. The plant uses state-of-the-art technology and design practices to reduce electrical demand and environmental impacts, while providing a critical water supply for the City.

The desalination plant is an important part of the City’s water supply portfolio which also includes surface water from Cachuma and Gibraltar reservoirs, groundwater, State water, purchased water, recycled water, and conservation.

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A Brief History

In the face of a challenging water supply crisis in the late 1980s, the City of Santa Barbara (City) constructed a seawater desalination plant as an emergency supply. The production capacity of the plant was 7,500 acre feet per year (AFY) with the potential for expansion up to 10,000 AFY. The neighboring water districts of Montecito and Goleta contracted for entitlements of 1,250 AFY and 3,069 AFY, respectively, during the five year contract period. The City had entitlement to 3,181 AFY. All sharing of costs for construction was based on these entitlements.

After the plant was constructed, it was operated between March and June of 1992. Due to abundant rainfall in the 1991-1992 winter and subsequent winters, the City’s drought condition was relieved and the desalination plant was placed into a standby mode. The $34 million total construction cost was paid off during the initial 5-year contract period by the City, Goleta Water District, and Montecito Water District, with a City share of approximately $14.5 million. However, the Goleta and Montecito Water Districts did not elect to extend or renew their interest in the plant after the initial five year contract period.

On June 4, 1991, City voters elected to make desalination a permanent part of the City’s water supply portfolio. With the approval of the Long Term Water Supply Program on July 5, 1994 (LTWSP1994) the City added the desalination plant to its permanent sources of water. An Environmental Impact Report on the LTWSP1994 was certified on May 24, 1994. On October 15, 1996, the California Coastal Commission issued a Coastal Development Permit to the City for permanent desalination facilities up to a maximum capacity of 10,000 AFY. The permit provided for intermittent and base load operation. Due to sufficient freshwater supplies since 1991, the plant remained in long-term standby mode for reactivation when water supply demand cannot be met using all other available supplies including extraordinary water conservation.

On July 21, 2015, in response to exceptional drought conditions, the Santa Barbara City Council voted unanimously to reactivate the Charles E. Meyer Desalination Plant. In May 2017, the startup testing at the plant was completed and the City started distributing desalinated water into the City's water system.

The capital costs to reactivate the facility were $72 million financed over 20 years with a low 1.6 percent interest rate loan, which equates to $4.2 million per year in debt service. In 2018, the City was awarded a $10 million dollar grant from the Department of Water Resources, which significantly reduced the overall cost of the project. The grant came from Proposition 1, a Water Bond passed by voters in 2014 to provide funding for water quality, supply, and infrastructure improvements. Annual operating costs are estimated to be about $4.1 million at full production and about $1.5 million in non-operation or standby mode. The plant could be put in standby mode during certain periods to reduce operating costs.

In 2015, City Council awarded IDE Americas, Inc. a design/build/operate contract to re-commission the desalination plant. Construction was finished in summer 2017 and the desalination plant began distributing water to City customers. The plant design includes a screened ocean intake structure equipped with openings of one millimeter, diluted and diffused brine discharge, and high-efficiency pumps and motors to reduce the plant’s overall electrical power demands.

Improvements in Desalination Technology

A lot has changed in desalination technology since the plant was built in 1991.

The reactivated plant…

Uses 40 percent less energy than the original design, greatly reducing its electricity demand and carbon footprint, by using high-efficiency pumps, motors, and improved filter technology.
Uses ocean intake pipes equipped with wedge wire screens recognized by the State Water Resources Control Board as a best available technology for screened open ocean intakes. The screens are made of durable copper-nickel alloy and have one millimeter openings to minimize marine life entrapment and impingement.

City of Santa Barbara Charles E. Meyer Desalination Plant

Aerial view of current desalination plant

Aerial view of the plant which produces three million gallons of drinking water per day. This is equivalent to about 30 percent of the City’s demand.

Treatment units where reverse osmosis is performed

In each treatment unit, seawater is first filtered through a sand and gravel media filter (similar to how water from Lake Cachuma is treated). Then the seawater is passed through reverse osmosis membranes that inhibit the passage of minerals (including salts) while permitting only water molecules to pass through.

Construction photo of the first treatment unit for MPD-A (modular process design) lifted into position. Construction to re-commission the desalination plant took two years to complete.

Sample of the 1 millimeter wedge wire screen used on ocean intake pipeline (with pen and remote control for size comparison). Recognized by the state as the best available technology for open ocean intake.