Case Studies

Sand City, California, a popular shopping and tourist destination on Monterey Bay, selected CDM to design-build a desalination facility to address the area’s diminishing water supply and facilitate city-wide redevelopment. The plant—which uses reverse osmosis (RO) and ultraviolet disinfection (UV) to treat highly brackish seawater—produces up to 600,000 gallons per day of potable water.

The Sand City desalination facility is the first full-scale, municipal desalination plant in California to receive permitting approval under the new surface water treatment regulations, establishing a precedent for the implementation of other planned seawater facilities in the state. Department of Public Health approval was achieved using beach wells as a means of pretreatment and providing additional pathogen removal beyond the levels currently required by California regulations.  

Design and construction of the facility also focused on energy efficiency and ease of operation, to ensure that water is provided at a cost comparable with existing supplies. Effective measures taken to reduce energy and operations costs for the facility include:

• Close collaboration during the design-build process, enabling increased efficiency, improved reliability, and simplified future operation.
• A reduced RO recovery rate results in lower feed pressures and improved water quality.
• Energy recovery devices reduce the size of the feed pumps by more than 60 percent.
• A single-rack RO skid design creates a small footprint in comparison to four individual skids.
• The elimination of acid in the treatment process simplifies chemical systems.
• Off-peak plant operation takes advantage of a low power demand reduced-rate structure.

CLIENT: City of Sand City, California

LOCATION: Sand City, California