By MICHAEL MCCABE, Chronicle Staff Writer
Oct. 27, 2000 (The San Francisco Chronicle)—Since the Bay Area is earthquake country, the people who control the flow of water are continually worried about what a major shaker might do to the water supply.
So why not link up with another water system's pipes, just in case?
Wednesday, the San Francisco Public Utilities Commission and the Santa Clara Valley Water District announced plans to do just that.
The project involves building a 1,000-foot-long, 42-inch diameter pipeline and pump station in Milpitas to connect the two giant water systems.
When the $9.1 million project is completed, it will allow San Francisco to deliver as much as 40 million gallons of water a day to the Santa Clara Valley Water District — or vice versa — if either one of the delivery systems were damaged in an earthquake, said Don Larramendy, superintendent of operations and maintenance at the San Francisco PUC.
"This is a major step in making our water delivery system more reliable in the event of a catastrophic earthquake," said Dennis Normandy, president of the San Francisco PUC.
The so-called Intertie Project will also allow both water systems to perform badly needed maintenance work and on-site inspections. The connector will allow small portions of each delivery system to be shut down, while water continues to flow from other sources, either from San Francisco or Santa Clara Valley. Officials hope to have it completed within a year.
"This project, which required nearly a decade of planning, will greatly benefit hundreds of thousands of Bay Area residents, not only in Santa Clara County, but in the greater Peninsula and South Bay," said Robert Gross, a director of the Santa Clara Valley Water district.
In the case of the Santa Clara Valley district, it allows engineers to continue a $200 million project to upgrade the Penitencia Water Treatment Plant and the county's two other water treatment plants, said Tom Dean, the district's deputy administrative officer.
Like many other water districts, Santa Clara Valley is moving away from using chlorine as the primary water disinfectant toward using ozone as the primary treatment, Dean said. He said they are also considering using ultraviolet light as a disinfectant as well as ozone.
San Francisco is eager to take advantage of the increased flexibility the connector will bring to embark on a $3.5 billion project to overhaul its 80-year-old water system.
First on the agenda is to inspect the Irvington Tunnel, a 3.5- mile-long bore blasted through sheer rock in the 1930s, Larramendy said. The 10.5-foot diameter tunnel, located in Fremont near Mission Boulevard, sits on top of the Hayward Fault and is considered a weak link in the system, he said.
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