This summer, Valley Water completed a major upgrade to the Coyote Percolation Dam. This important structure helps us achieve our mission to provide safe, clean water to Santa Clara County.
The dam is located in San Jose on Coyote Creek, just north of Metcalf Road. For many years, it has helped store water in the Coyote Percolation Pond, where the water slowly seeps into the ground to refill our underground water supplies.
With the completion of the Anderson Dam Tunnel Project in 2026, Coyote Creek is expected to carry significantly more water. The current infrastructure at the Coyote Percolation Dam was not equipped to handle these increased flows. However, removing the dam entirely would have disrupted groundwater recharge operations.
Instead, Valley Water replaced the old flashboard dam with a state-of-the-art inflatable bladder dam. This modern system provides greater control, allowing us to raise or lower the dam to adapt to changing creek conditions. This enables us to maintain recharge operations during low flows and safely pass higher volumes of water during storms.
Valley Water will start refilling the Coyote Percolation Pond after the dam’s electrical power upgrades are finished, which is scheduled for late 2025.
In addition to replacing the dam, this project includes a revamped fish passage and construction of a new operations control building. The improved fish passage includes a new lane and motorized adjustable weirs on the updated fish ladder to help ease migration through the creek.
By investing in this project, Valley Water is securing a reliable water supply for Santa Clara County and enhancing the region’s natural resources.


This project is located in San Jose not Morgan Hill as stated in the article. Do your research or get an editor!
Thanks for catching this mistake. We have updated the article.
What is the estimated date for completion of the Anderson dam project?
Hi Debbie,
Thanks for the question. Our estimated timeline shows the Anderson Dam project will be completed in 2033. In case you are interested, we regularly update keep the project web page with information. https://www.valleywater.org/project-updates/c1-anderson-dam-seismic-retrofit
Great job, water conservation is the most important we will be facing.
Can you share the overall timeline for the Anderson Dam project (inception to project completion)? It seems like this project is in the 20-30 year range, right?
Hi Tim,
The overall timeline includes the start in Fiscal year 2014 and anticipated completion in Fiscal Year 2033