Groups join for water study

Three communities have taken the next pivotal step in developing a new water source from a sea water desalination facility in southern San Luis Obispo County.

Arroyo Grande, Grover Beach and the Oceano Community Services District entered into an interagency agreement to determine how viable desalination is as an option to provide additional potable water and ensure their supplies won't run dry in coming years.

Dubbed the South San Luis Obispo County Desalination Funding Study, it's a roughly $100,000 undertaking. About $45,000 of the cost will be funded by a Proposition 50 grant through the State Department of Water Resources.

Each city and OCSD will pay one-third of the remaining cost for the study.

The study is aimed at providing an in-depth analysis of a preliminary design of a plant, which could be located at the South San Luis Obispo County Sanitation District Wastewater Treatment Plant, as well as overall cost, environmental impacts and a probable time frame.

All would be required to determine the project's viability, officials said.

“We're continuing down the process to refine the project and identify the specifics,” said Don Spagnolo, director of public works and city engineer for Arroyo Grande, the lead agency.

Desalination has been singled out as the best option for the three communities' future water needs instead of attempting to extend the Nacimiento pipeline that will bring water to San Luis Obispo.

The desalination process consists of using one of several techniques to reduce the number of dissolved solids in ocean water to a potable level and treating it so it matches the taste and quality of other drinkable water.

Previous studies have shown that a supplemental water source is needed to enhance the reliability of existing water supply, officials said.

Technically, the study, scheduled to be performed by the Wallace Group, would cover preliminary design of the recommended seawater intake system and reverse osmosis filtration system, design of a combined wastewater treatment ocean outfall and brine disposal system, design of an energy recovery system and outline of a distribution system, officials said.

If the project is eventually approved, a similar cooperative agreement would likely be considered for operation of the facility, officials said.

Arroyo Grande City Council will next discuss a consultant service agreement and contract with the State Department of Water Resources for grant funding at its Sept. 25 meeting, Spagnolo said.

Josh Petray can be reached at 489-4206, Ext. 5015, or jpetray@santamariatimes.com.

September 23, 2007