Monterey desalination plant moves forward

Desalinated water could come to the Monterey coast of California “as soon as 2012”, according to the Marina Coast Water District.

The California Public Utilities Commission (CPUC) certified the final Environmental Impact Report (EIR) for the Coastal Water Project on 17 December 2009.

The Coastal Water Project would consist of several distinct components: a seawater intake system; a desalination plant; a brine discharge system; product water conveyance pipelines and storage facilities; and an aquifer storage and recovery system.

CPUC and its administrative law judge assigned to the Coastal Water Project application are expected to consider adoption of components of the Coastal Water Project early in 2010. Simultaneously, the partners in a local publicly owned alternative (the Monterey Regional Water Supply Project) will consider the components for adoption on the National Environmental Policy Act (NEPA) using the final EIR as a basis for their deliberations.

Partners in the regional project are Marina Coast Water District, Monterey County Water Resources Agency, Monterey Regional Water Pollution Control Agency along with California America Water (Cal Am). Cal Am has also put forward two alternative proposals known as the Moss Landing and North Marina projects. These are also considered viable by the EIR.

Each of the three projects would involve a seawater desalination plant of around 40,000 m³/d. The regional project would use most of the components of the North Marina proposal in a wider integrated supply project. It would also, however, use vertical beach wells for the intake instead of the North Marina proposal’s slant wells.

An issue still to be resolved, however, is who will own the desalination plant. Monterey county law bars private companies like Cal Am from owning water supply facilities. The regional plan proposes that the plant should be owned by Marina Coast WD, which should sell the water to Cal Am.

“Going forward with a NEPA evaluation opens up doors for federal grants and low-cost state loans to reduce final design and construction costs, thus making the publicly owned project cheaper and rates lower when water is delivered to Central Coast customers,” said Jim Heitzman, general manager of the Marina Coast Water District.

CPUC has expressed support for the regional project among the alternatives, and Cal Am, which has been ordered by the State Water Resources Control Board to reduce pumping from the Carmel River aquifer, is negotiating with the public water agencies to support the Regional Water Project in financing and purchase of future water supply.

Cal Am needs to find an alternative source to the Carmel River aquifer for about 10,000 acre-feet (12.3 million m³) of water per year.

“That is why planning and implementation of the Regional Water Project has become critical,” Heitzman said. “There is a need to replace that water supply to sustain the lifestyle and economy of Monterey County. The Peninsula is being told by the state to dramatically lower water use. We need to provide alternative water supplies now.”

“The Regional Desalination Plant location meets Coastal Commission restrictions on open ocean intake and treats a combination of ocean and brackish groundwater,” Heitzman said. “Potential use of nearby Monterey Regional Waste Management District methane gases to generate power contributes to reduction of greenhouse gases and supplies a sustainable energy source.”