Valley Water, the local water district that is in charge of rebuilding the dam at Anderson Reservoir in Morgan Hill, recently released a draft environmental study of the seismic retrofit project.
The district is now accepting public comment on the Anderson Dam Seismic Retrofit Project Draft Environmental Impact Report (EIR). As part of the public input effort, Valley Water will host a meeting on Oct. 4 in Morgan Hill where staff will make a presentation on the project and its draft EIR, as well as receive input from attendees.
The draft EIR was released by Valley Water on Sept. 1. The document identifies the potential environmental impacts of the seismic retrofit of Anderson Dam, which was deemed necessary after authorities in 2009 found that the existing earthen structure near Cochrane Road could fail in the event of a major earthquake.
The draft EIR also considers the impact of additional conservation measures proposed by Valley Water in relation to the dam embankment reconstruction, according to Valley Water staff.
The release of the draft was hailed by Valley Water earlier this week as a “milestone” for the Anderson Dam project, a multi-phase effort that is projected to cost more than $1 billion.
Also this week, Valley Water revealed that crews are nearly halfway through the excavation of the current project phase—the Anderson Dam Tunnel. The district’s contractors have excavated more than 800 feet of what will be a 1,736-foot tunnel that leads from the base of the dam into the bottom of Anderson Reservoir.
Earlier this month, crews began the controlled blasting of hard rock as they proceed with the tunnel excavation.
When complete, the tunnel will give the water district significantly more control over the reservoir’s water levels.
“Rebuilding Anderson Dam is Valley Water’s top priority,” Valley Water Board Chair John L. Varela said. “I am thrilled to see tremendous progress on the tunnel project. Rebuilding Anderson Dam will allow Valley Water to help ensure public safety, protect our regional water supply and provide environmental benefits for future generations.”
Valley Water has also begun the process of seeking permits from the Federal Energy Regulatory Commission, by releasing a Draft Petition for Surrender of Exemption for a 90-day review period. That petition is related to an existing hydropower plant at Anderson Dam that Valley Water plans to decommission as part of the seismic retrofit project.
According to Valley Water’s website, “The Draft Petition explains Valley Water’s plan and reasoning for surrendering the existing permit to operate the hydroelectric plant. The document also includes additional biological and environmental reports to support FERC’s permitting process.”
According to the draft petition submitted by Valley Water, the hydroelectric facility was constructed by the district in the mid-1980s. The facility includes a powerhouse with a maximum capacity of 800 kilowatts and a 100-foot-long transmission line connecting the plant to the electrical grid.
The plant was operational almost every year from 1988-2019, with some exceptions due to drought conditions and maintenance work, according to Valley Water staff.
An economic analysis of the hydroelectric facility conducted by Valley Water in December 2020 found that, throughout the plant’s life, it has “generated approximately 39,700,000 kilowatt-hours of renewable energy, valued at approximately $2,910,000, at an operation and maintenance cost of $3,450,000,” says the draft petition.
In recent years, Valley Water has not been able to operate the hydropower plant due to low water levels, capacity restrictions due to the dam’s seismic condition and prohibitive maintenance costs.
And in 17 out of the last 18 years of the plant’s life, it operated at a loss of revenue, with an average loss of $75,000 per year over its last 10 years, Valley Water staff said.
The public can comment on the draft petition, which is posted on Valley Water’s website at tinyurl.com/5n9anuh5.
Residents, property owners and other interested parties can submit comments on the Anderson Dam Seismic Retrofit Project draft EIR until 5pm Nov. 1. That document is also on the district’s website at tinyurl.com/2p8pv7vw.
Public review period is open
The Oct. 4 meeting on the draft EIR will take place 6:30-8pm at the Morgan Hill Community & Cultural Center, 17000 Monterey Road. The meeting will also be streamed online. To attend remotely via Zoom, visit valleywater.zoom.us/j/87331718480.
The Draft EIR is also available for in-person review during normal business hours at three locations: Valley Water, 5750 Almaden Expressway, San José; Morgan Hill City Clerk’s office, 17575 Peak Ave.; and the Morgan Hill Library, 660 West Main Ave.
Written comments on the Draft EIR can be submitted electronically or by mail by 5pm Nov. 1. Written comments can be emailed to [email protected] or mailed to:
Tiffany Chao, Senior Environmental Planner
Santa Clara Valley Water District
5750 Almaden Expressway, San José, CA 95118.