The Project
The People’s Moss Landing Water Desalination Project (“PMLWDP”) is a proposed desalination plant in Moss Landing that will produce 13,404 acre foot per year of potable water. The overall purpose of the PMLWDP is to rehabilitate existing facilities at the Moss Landing Green Commercial Park to develop a desalination project in order to provide potable water to the North Monterey County
area and to the Monterey Peninsula. The PMLWDP will provide 3,652 afy of “new water” to customers in North Monterey County and 9,752 afy to the Monterey Peninsula, to offset mandated water supply diversion curtailments on the Carmel River and Seaside Basin. The proposed PMLWDP would be comprised of the following major facilities:
Open Bay Seawater Intake Facility: The proposed open bay seawater collector system would draw seawater from the Monterey Bay for use as source water for the proposed desalination plant. Approximately 28 to 30 mgd of source water would be needed to produce approximately 12 mgd (13,404 afy) of desalinated product water. The preferred site for the open bay system would be located within an existing 20-foot diameter intake pump structure that is located on the beach and adjacent to the Moss Landing Marine Laboratories. The existing intake caisson (built in the 1940s) would be rehabilitated to include a new 30-inch intake pipe and two (2) wedge wire passive screens that would be 48 inches in diameter and would draw in seawater into the existing caisson. The screens will be designed for a maximum through-screen velocity of 0.5 ft/sec and 0.5mm wedge wire slots to minimize impingement and entrainment. Water Conveyance Into Facility: A new pump house would be built on top of the existing intake structure at a height of approximately 15 feet above sea level so that the pumps would be outside of the tsunami zone. A new 30-inch pipeline would be slip-lined within the existing 36-inch intake pipeline to convey the seawater (or “source water”) into the People’s Moss Landing desalination plant. Desalination Plant: The People’s Moss Landing Desalination Plant and appurtenant facilities would be located on a 16.5 acre site at the Moss Landing Green Commercial Park. Facilities proposed at the site include pretreatment, reverse osmosis, and post-treatment systems; chemical feed and storage facilities; a brine storage basin, and an administrative building. Ocean Outfall Facility: Brine produced during the desalination process would be conveyed through the existing 51-inch ocean outfall pipeline, which would be rehabilitated with new diffusers prior to discharging to the Monterey Bay. Conveyance and Storage Facilities: Desalinated water conveyance facilities, including a 5 million gallon clearwell, pump station, a new 17.5 mile pipeline conveyance facility and a new 5 million gallon terminal reservoir system to interconnect with Cal-Am’s System at Seaside, CA. Specific water storage and conveyance facilities for the North Monterey County Area needs will be determined after consultation with applicable water districts and companies.
