Water Treatment Plant Expansion and Treated Water Reservoir

Scheduled for completion by May 2019, the 81 WSIP projects stretch from California’s Central Valley to San Francisco, along the landmark regional water system, delivering water to more than 2.6 million people in the San Francisco Bay Area.

The program is funded by a bond measure that was approved by San Francisco voters in November 2002 and will be paid for by both retail customers in San Francisco and 26 wholesale customers that serve Alameda, San Mateo and Santa Clara counties.

The WSIP objectives include:

• Improve the system to provide high-quality water that reliably meets all current and foreseeable local, state, and federal requirements.
• Reduce vulnerability of the water system to damage from earthquakes.
• Increase system reliability to deliver water by providing the redundancy needed to accommodate outages.
• Provide improvements related to water supply/drought protection.
• Enhance sustainability through improvements that optimize protection of the natural and human environment.

The Water Treatment Plant is sited on land owned by the SFPUC in Alameda County, CA. The plant treats water from two local reservoirs before the water is served to its customers. It also filters Hetch Hetchy water on the occasions when the Sierra supply does not meet drinking water standards for filtration avoidance. Should the Bay Area be cut off from Hetch Hetchy supplies because of an emergency, the treatment plant must sustainably treat 160 million gallons of water a day to meet minimum customer demands.

Completed as a joint venture of MWH Americas Inc., Lee Environmental Engineering Inc. and AGS, Inc., the project has improved plant reliability, by adding a fifth flocculation and sedimentation basin, retrofitting existing filters, adding a new chlorine contact tank and creating a 17.5 million gallon circular balancing reservoir for treated water as it leaves the plant. The project includes new connections and facilities that will enable the plant to treat enough water to meet basic customer demands alone, for up to 60 days after a major earthquake. These improvements will help increase delivery reliability and water quality to the Hetch Hetchy Regional Water System.

• Geotechnical Investigation and Engineering
• Site Surveying
• Process optimization
• Design engineering
• Engineering Services During Construction
• Start up and operator training
• Operations Manual update

American Public Works Association, Project of the Year Award—Environment more than $75 million category