News Events

Member Agency

Metropolitan at Work

Press Releases

Board Meeting Materials

Who is Metropolitan?

Doing Business with Metropolitan


Be a bewaterwise
fan on Facebook

Be a Metropolitan
fan on Facebook

Water Supply Alert
Water Alert

Share |
May 2010

Weymouth Treatment Plant Turns 70

Click here to view more Weymouth photos

Sedimentation basin at Weymouth

The fountain at the end of the north covered walkway near the entrance to the
main admin building.

The La Verne complex is named for Frank E. Weymouth, who served as Metropolitan's first general manager and chief engineer from 1929 to 1941 and directed construction of MWD's Colorado River Aqueduct and initial distribution system.

Weymouth, one of Metropolitan's five treatment plants, ranks as one of the largest water treatment facilities in the United States, with a design capacity of 520 million gallons per day for distribution to Los Angeles and Orange counties.

Originally called a “water softening” plant designed to remove salt from Colorado River water, Weymouth also began treating Northern California supplies with the completion of the State Water Project in the 1970s. The Weymouth plant is a conventional water treatment plant utilizing chlorine for disinfection and the use of flocculation, sedimentation and filtration to remove the suspended particles from the water.

Closeup view of the roof
tower of the main admin

The facility is also home to Metropolitan’s high-tech water quality laboratory, which opened in 1985. The laboratory conducts some 300,000 water quality tests a year.

The 70-year-old plant is undergoing extensive rehabilitation with upgrades to the electrical system, influent conduit, basins and filters in various stages of design and construction. In addition, Weymouth will be the last of the five treatment plants to use ozone gas as the primary disinfectant. The design of the ozone system for Weymouth is nearing completion with construction expected to start soon. Design is also underway on a one-megawatt Weymouth solar power generation facility.

This newsletter is produced by the:
Metropolitan Water District of Southern California
700 N. Alameda St.
Los Angeles, CA 90012