Valley Water executives are moving forward with the development of a new dam at Pacheco Pass in southern Santa Clara County, although they recently learned that the price has doubled since 2019.
“It seems to me that the directors of the water district need to take whatever extreme measures we can find to continue this project, move it forward and work with environmental groups as we always do,” said the district director. of Santa Clara Valley Water, John Varela. “(We have to) find the solution, find the resources to do this and get there.”
Trustees voted unanimously on Jan. 12 to continue developing and reviewing plans for the project.
Valley Water first unveiled a plan in 2017 to build a dam to expand the Pacheco Reservoir to increase local water amid increasing drought. The proposed site is approximately a 30-minute drive east of Gilroy, between Henry W. Coe State Park and Pacheco State Park. The project would increase the reservoir’s capacity from 5,500 acre feet to 140,000 acre feet of water.
Valley Water officials say that’s enough water to supply 1.4 million people for a year.
In 2017, cost estimates put the project at around $ 970 million. By 2019, that price had risen to around $ 1.2 billion, factoring in inflation.
Now, district officials envision a cost of $ 2.5 billion, after studies showed that deeper excavations would be needed to build the dam foundation at the proposed site. The quality of the rock would also require a reconstructed spillway to improve stability, increase the price, as well as a longer construction schedule.
Project managers now believe it will take eight years to complete the dam. The previous estimate was only five years.
Earlier this month, Ryan McCarter, project manager for the Pacheco Pass dam, presented five options to Valley Water directors for consideration. Each of the five alternatives contemplates either a different dam location, alternative dam construction, lower reservoir capacity, or a combination.
“If we don’t break this down today, I guess your idea is to study these five alternatives and then make a recommendation or bring it back to us to make a decision,” said District 4 director Linda LeZotte. “I think at this point it would be very important to know which clearing obstacles we are looking at after you have had a better time to refine them. “
Project officials said no subsurface survey was done at the start of the project, meaning no drilling was done to determine whether the site would support the dam or not. The area surrounding the proposed dam site is mostly private property, managers said, so it was difficult to complete this work.
Representatives from the Loma Prieta section of the Sierra Club expressed growing concern in a letter to the directors, saying the project is no longer viable.
“The extraordinary cost increases signal further escalation in costs and unacceptable increases in water charges in the future, and lower cost alternatives to provide the same benefits are available,” wrote Katja Irvin and Gladwyn d’Souza. in the Sierra Club letter. “The extreme environmental impacts that would result from this project are certainly no longer justifiable, if they ever were. “
The Sierra Club has warned that approval of the project could cause water rates to increase in parts of the county by about 145% over the next 10 years.
Valley Water spokesman Matt Keller confirmed the 145% increase was “possible,” but said it would help fund all projects in the district. The Pacheco Pass dam would account for 17% of this increase.
Although they approved the sequel, some directors expressed various reservations about the project.
“For now, I keep an open mind for this project,” said District 5 director Nai Hsueh. She said she believed the price would continue to rise due to inflation and other unforeseen costs.
But after project managers told directors they believed the agency’s partners could foot 20% of the bill, Hsueh hit back.
“I’m not sure these assumptions are realistic,” she said.
Valley Water officials said they would work on greater community outreach from February and expect to have a draft environmental impact report by the end of 2021.
Contact Madelyn Reese at [email protected] and follow her @MadelynGReese on Twitter.
Editor’s Note: Rick Callender, CEO of Valley Water, sits on the San José Spotlight Board of Directors.