Press Release

California Water Service Begins Main Replacement Project in Woodside and Portola Valley

MENLO PARK, Calif. — Water system reliability and water quality improvements are underway for California Water Service (Cal Water) customers in Woodside and portions of Portola Valley as new water mains are placed into service. Cal Water will also install four fire hydrants to increase firefighting capabilities.

More than 3,000 feet of 12-inch ductile iron and 8-in PVC pipe will be installed in the 400 block of Whiskey Hill Road and will extend to Sand Hill Road and Manzanita Way. Construction is expected to be completed by late September.

The new main will also create an alternative delivery route in the distribution system to provide water to Woodside and parts of Portola Valley, allowing customers to stay in service, ensure proper flow, and maintain consistent supplies to storage tanks during natural disasters, repairs, and peak periods of demand.

This project is part of Cal Water's systematic infrastructure maintenance and upgrade program. An additional 25,000 feet of new main is expected to be installed by the end of the year in the Bear Gulch District.

Construction will take place between 9 a.m. and 3 p.m. Mondays through Fridays. Some traffic delays or detours may occur; however, city-approved traffic plans will be put into place.

"We will do our best to minimize any traffic impacts and will ensure the streets are left in good condition when the project is complete," said Cal Water District Manager Dawn Smithson. "This important water system upgrade will help us better serve our local customers for years to come."

Cal Water serves about 60,000 people through 18,900 service connections in Atherton, Portola Valley, Woodside, and Menlo Park. The company, which has provided water service in the area since 1936, was ranked "Highest in Customer Satisfaction among Water Utilities in the West" in 2016 by J.D. Power in its inaugural Water Utility Residential Customer Satisfaction Study. Additional information may be obtained online at