San Mateo and Foster City celebrate opening of wastewater treatment plant
San Mateo and Foster City officials recently cut the ribbon on their new wastewater treatment plant. The wastewater treatment plant is the largest infrastructure improvement project in San Mateo’s history. The plant began construction in 2019. The completion was highly anticipated and opened in September 2025, after setbacks from the pandemic. This was a joint effort from San Mateo, the Estero Municipal Improvement District which represents Foster City
The plant will treat wastewater for about 150,000 residents with an added aim prevent sewer overflows and unsanitary water from reaching the San Francisco Bay. It came with a total cost of around $500 million through state and federal funding.
“While wastewater treatment may not seem glamorous, it is essential to public health,” said San Mateo Mayor Rob Newsom. “It’s the quiet work that protects public health, safeguards our environment and gives cities peace of mind.”
