MORGAN HILL, Calif. (KGO) -- Federal dam regulators are ordering the biggest reservoir in Santa Clara County to be drained because of earthquake risk.
The Anderson Reservoir sits between Morgan Hill and San Jose, located just east of Highway 101.
For years, Valley Water has led the push to rebuild the Anderson Dam. However, plans have been met by obstacles.
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In a release to ABC7 News, Valley Water described the Anderson Dam Seismic Retrofit Project (ADSRP) as both "complicated and time-consuming."
Valley Water CEO Norma Camacho added, "Valley Water has been working with several state and federal agencies through the years to secure the proper permits as the scope of the project has increased due to additional safety and design requirements, while also complying with federal statutes and regulations, including the National Environmental Policy Act, Endangered Species Act, National Historic Preservation Act, and Clean Water Act."
According to Valley Water's website dedicated to the project, the status is "on target," and ADSRP is in the "planning" phase.
In a letter written by the Federal Energy Regulatory Commission (FERC), the Division of Dam Safety and Inspections Director, David Capka said, "Until full remediation is completed, the dam safety risk at this project is unacceptably high."
The letter to Christopher Hakes, the Deputy Operating Officer of Valley Water's Dam Safety and Capital Delivery Division continued, "Your actions to date do not demonstrate an appropriate sense of urgency regarding the interim conditions at the project."
FERC ordered the reservoir to be drained, by Oct. 1, so work can start.
Residents in the surrounding community are also demanding action.
"I never saw any work done during the day," Morgan Hill resident, Manuel Orozco said. "It made me a little skeptical, wondering okay... that's what we're paying $500 million for."
According to Matt Keller with Valley Water, the latest project estimate puts the cost at $563 million.
Keller explained a parcel tax, approved by voters in 2012 will cover $65 million, and much of the money will come from increased water rates.
The fear in all of this is that a powerful earthquake could damage the dam, and send a wall of water into surrounding communities.
While Valley Water publicly agreed with the need to move quickly, it shared concern about unsafe consequences.
Camacho's statement included, "With the draining of the reservoir, experts would expect fish die-offs. The inability to keep a consistent flow in Coyote Creek downstream of the dam year-round would significantly impact sensitive native fish, amphibians, reptiles, wetlands, and riparian habitats. Water quality could also be significantly impacted downstream of the dam."
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Morgan Hill resident Suzy Buck told ABC7 News, "I know it won't be forever. I know it'll just be for a little while until they remedy the situation. But until then, I think wildlife has a way of surviving no matter what."
Valley Water's top concern is potential damage to the intake structure. According to Camacho, this would leave the district without any control over water flowing out of the reservoir. Ultimately, impacting communities downstream.
The potential areas of impact include parts of San Jose which were inundated in the historic floods of February 2017. Back then, water from the Anderson Reservoir flowed over the banks of Coyote Creek and into several communities.
"It affected a lot of people that were living near the creeks," San Jose resident, Habibullah Norzaie said. "And personally, because I'm a student at San Jose State, I saw lots of flooding along the roads and the streets."
Camacho's statement explained, "Anderson Reservoir is currently operating below the current levels required by FERC and the state Division of Safety of Dams."
"A priority will be to design and build a large outlet pipe, which will provide greater control over the water levels and increase public safety," she continued.
Camacho said Valley Water staff is already exploring other sources of water that will have to come from outside of the county.
"While residents have done an excellent job of conserving water since 2013, another drought during this timeframe could require everyone to significantly decrease their water use," Camacho warned.
A bill has been introduced in the California Legislature to help expedite the regulatory process and move the project along as quickly as possible.
Click here for detailed information about the Anderson Dam Seismic Retrofit Project.
Feds order Anderson Reservoir be drained to allow necessary earthquake retrofitting
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