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San Jose Stanches Fresh Flows
Up to 21 million gallons of treated wastewater now being discharged into the South Bay each day - wastewater that is rapidly converting salt marsh habitat for endangered species into freshwater marsh -will be diverted to industries for reuse, and onto golf courses and parks for irrigation by the closeof 1997.
To help accomplish this feat, San Jose and other South Bay cities are now completing over $140 million worth of new pipes, pumps and other wastewater recycling facilities. This infrastructure will divert the 21 mgd of tertiary-treated effluent to over 300 private and public agency recycled-water customers in San Jose, Milpitas, and Santa Clara.
It starts with a new pumping station near the treatment plant and connecting 108-inch-diameter pipe. From there, 60 miles of newly-laid pipeline will take the recycled water in three branches along flood control and railroad rights-of-way and beneath surface streets to the three cities. In San Jose, two new pumping stations will add pressure and equalize the flow, so the water can be carried up into the hills. At the last pumping station, the city will build a small reservoir for temporary storage. A retrofit grant program will help recycled-water customers finance the on-site improvements needed to keep recycled and potable water separate.
As an incentive to encourage its use, rates for the recycled water will be considerably lower than those for potable water. The recycle-bound wastewater will come from the San Jose/Santa Clara Water Pollution Control Plant, which treats water from all or portions of 8 South Bay cities and in 1996 discharged an average of 132 million gallons into the Bay per day, 12 million gallons in excess of the 120 mgd maximum imposed by the S.F. Regional Board in 1991.
Part of the problem for the San Jose plant is that it's a shallow bay discharger, which means its effluent must be more diluted than that of deep-bay dischargers like East Bay MUD. A bigger problem is the Silicon Valley and South Bay economic boom, and its spiraling increases in wastewater loads.
The new recycling facilities are just one part of a $258 million, three-part action plan - first approved in 1991 and now being implemented - for reducing discharges. The second part expands a 1980s water conservation/education program to emphasize rebates for homeowners and commercial property owners who install ultra-low-flush toilets. The third part - purchase and some restoration of two tracts of salt marsh totaling 404 acres - mitigates for 380 acres of salt marsh converted to freshwater marsh between 1970 and 1985 as a result of plant discharges.
Once the 21mgd begins coursing through the recycling pipeline, it should help the South Bay get back down to the 120 mgd limit in its discharge permit. A revised plan for how to keep this lid on in the years ahead goes to the Board in May, with a public hearing scheduled for June 18. "Just putting more pipes in the ground could break our residents' backs, in terms of costs we have to pass on," says the city's Lindsey Wolf. "We're looking at a whole range of measures for maintaining the 120 mgd while continuing to grow. No one wants a moratorium on growth."
Some scientists and environmentalists question whether the program, however ambitious, will succeed in stopping further salt marsh conversion. "My guess is that at 120 mgd, the conversion would continue," says Howard Shellhammer, a San Jose State University salt marsh harvest mouse expert. Shellhammer and other biologists have noticed less of the endangered mice in the South Bay. As Cal Fish & Game's Deborah Johnston explains, "People are just now starting to realize the extent of the change that has occurred." Shellhammer predicts that as water demands continue to grow, the city's options for reducing discharges could become cost-prohibitive and unsustainable.
Greg Karras, with Communities for a Better Environment, points out that discharges in excess of 120 mgd are partially due to industrial wastewater, and claims that many companies have already proved they can recycle more water inside their plants cost-effectively. "There's every indication we can solve this problem," he says. "The only issue is whether the cities and industries can start reducing the flows now, before more salt marsh is converted to fresh."
Contact: Lindsey Wolf (408)277-5533
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