San Jose
– South County has at best only 50 percent of the water supply
necessary to support San Jose’s development schemes for Coyote
Valley, though a water district official said Tuesday that she
expects a combination of conservation and recycling efforts will
meet the future water demands of the city’s
southern edge.
San Jose – South County has at best only 50 percent of the water supply necessary to support San Jose’s development schemes for Coyote Valley, though a water district official said Tuesday that she expects a combination of conservation and recycling efforts will meet the future water demands of the city’s southern edge.
Preliminary projections place the amount of water needed to support a Coyote Valley of 25,000 homes, 50,000 jobs and 80,000 residents at 16,000 to 20,000 acre-feet annually. As it now stands, the Coyote groundwater sub-basin has enough water to supply only 8,000 acre-feet of water per year. An acre foot of water is equal to an area about the size of a football field filled to a depth of one foot, or the amount of water needed to support a family of five for one year.
Currently, there are no recharge avenues for Coyote Valley other than Coyote Creek, meaning that the proposed neighborhood will be entirely reliant on the present capacity of groundwater sub-basin. The Santa Clara Valley Water District is responsible for meeting the water demands of Coyote Valley, which has been in San Jose’s general plan for decades and is part of the district’s long-term supply plan for South County.
Melanie Richardson, assistant operating officer for the district’s water supply management team, said Tuesday that Coyote Valley is an opportunity for the district to employ new technology and techniques for conserving and recycling water.
“With a new development you have the opportunity to do things from the ground up,” Richardson said. “There’s no doubt that it’s getting harder to find new water, but this in an opportunity to be more efficient with the local supply.”
Later this month, the district will present a set of recommendations to San Jose officials about how the city can make better use of the water in the Coyote basin, and in the next year the district will begin plotting ways to meet the shortfall, which won’t occur until the development approaches full build-out, which is at least 20 years away.
The district’s task is further complicated because it’s in the position of providing water directly to residents.
“Normally we would do that with a retailer,” CEO Stan Williams said. “In Coyote Valley, we don’t know who that is.”
Financing decisions on any new projects will be made down the road, but Richardson said she assumes the district will pass along costs to users in water rates. She said residents south of Coyote Valley will likely not be affected by projects for that neighborhood.
Options for Coyote Valley include adding recharge capabilities to the groundwater basin and expanding capacity and use of recycled waste water, perhaps using technology to treat reclaimed water to potable levels. Reclaimed water in South County is currently used only for agriculture, watering parks and powering energy facilities.
But even those options are not available to Coyote Valley. The groundwater there is so close to the surface that any use of recycled water threatens to contaminate the groundwater, a point stressed by district board member Joe Judge.
“It’s just a big bathtub out here and Coyote Creek is the drain,” Judge said at a summit meeting Tuesday between the water district and San Jose’s city council. “The underground is exceedingly sensitive. I want people to know I have a lot of questions.”
Richardson said that preserving the purity of the groundwater would remain the district’s top priority and that the district will expend a lot of time in outreach and education efforts about the use of reclaimed water.
Coyote Valley developers and homebuilders can conserve water by building homes with dual plumbing that allows use of reclaimed water for toilets, mandating use of water-efficient appliances and planting native landscaping.
Coyote Valley water facts
• Annual acre-feet needed to support development of Coyote Valley: 16,000-20,000
• Annual acre-feet available in the Coyote Valley sub-basin:
8,000
• An acre-foot is equivalent to an area about the size of a football field filled to a depth of one foot, or about enough water to supply a family of five for one year.
