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Resource Issues: Desalination Project Details
Monterey Peninsula Water Supply Project - #NOAA-NOS-2016-0156

Project Description

The purpose of the Monterey Peninsula Water Supply Project (MPWSP) is to replace existing water supplies for CalAm’s Monterey District service area. It comprises various facilities and improvements, including: a sub-surface seawater intake system; a 9.6-million-gallons-per-day (mgd) seawater reverse osmosis (SWRO) desalination plant; desalinated water storage and conveyance facilities; and expanded Aquifer Storage and Recovery (ASR) facilities. The desalination facility would be capable of producing 10,627 acre-feet per year (AFY) of potable water on a 46-acre site located north of the City of Marina on unincorporated Monterey County property. The MPWSP proposes ten subsurface slant wells to draw seawater from beneath the ocean floor in Monterey Bay to produce the source water for the desalination plant. The subsurface slant wells would be located primarily within the City of Marina, in the active mining area of the CEMEX sand mining facility. The slant wells would be approximately 700 to 1000 feet in length, with well tips located at approximately 200 to 220 feet below mean sea level. Up to 24.1 mgd of source water would be needed to produce 9.6 mgd of desalinated product water. The desalination plant would generate approximately 13.98 mgd of brine, including 0.4 MGD of decanted backwash water. The brine would be discharged into Monterey Bay via a 36-inch diameter pipeline to a new connection with the existing Monterey Regional Water Pollution Control Agency’s (MRWPCA) outfall and diffuser located at the wastewater facility.

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URL:    Reviewed: November 20, 2017
Web Site Owner: National Ocean Service

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