Recycled water system to be put to test at development near Tracy
Occupants of 11,000 new single-family houses under construction near Tracy will be able to recycle their shower, bath, laundry and sink water on site using a system designed by Australian water engineers, one of dozens of new water technologies the White House will showcase at its big “water summit” Tuesday.
Hoping to leapfrog a Congress still trying to wring more water out of California’s over-drafted rivers, the Obama administration wants to replicate for water the push it made on solar power nearly eight years ago to jump start new technologies and coordinate the federal response to droughts.
President Obama views efforts to address climate change as a key piece of his legacy, and White House officials view drought as among the most dire consequences of a warming climate. After last fall’s climate talks in Paris, the administration immediately targeted water as a priority.
The White House issued a government-wide directive Monday to reduce the nation’s vulnerability to drought, which it said “poses a serious and growing threat to the security and economies of communities nationwide.” Toward that effort, administration officials said 150 businesses and nonprofits will pledge $4 billion in private capital to improve water resiliency.
World Water Day
White House science adviser John Holdren, who has been helping drive the administration’s water policy, said Tuesday’s summit was planned to coincide with World Water Day, and while it comes at the tail end of the Obama presidency, “we’ll be passing along a lot of good ideas about what works and what doesn’t.”
Technically known as “gray water,” the soapy effluent of showers, sinks and laundry has long been an obvious source of new water supply. Most of the focus, however, has been on building large recycling plants that ferry household sewage to a centralized treatment plant.
Treating gray water within each home is “conceptually sort of like solar panels,” said Ralph Petroff, co-founder and chairman emeritus of Nexus eWater, an Australian startup that moved to California last year. The company designed the system employed at River Islands, a master-planned development in the town of Lathrop (San Joaquin County), near Tracy. The company calls the project “the first major development in the world” to combine on-site gray water reuse with recycled energy from the home water heater.
“When the energy crisis hit, people said, ‘Let’s build huge power plants,’” Petroff said. But that takes decades and cost tens of billions of dollars, he said, so rooftop solar began catching on.
“There is a similar dynamic now,” he said. “People say, ‘We’ve got a water crisis. We need a lot more water, so we’ll build recycling and desal (desalination) plants,’ and it’ll take 15 years and cost billions. So our solution, similar to solar panels, is to do it on-site and do it during construction.”
The houses will have separate gray-water plumbing, with two underground tanks and a recycling unit about half the size of a refrigerator turned on its side, said Nexus eWater chief executive Tom Wood. The system adds $8,000 to $10,000 to the cost of each house, but will be amortized in a monthly bill partially offset by savings in water and sewer charges. The water can be used to flush toilets but mainly will go outdoors for landscaping and car washing. The system does not include toilet or kitchen waste, so-called black water, but still can reduce household use by an estimated 40 to 60 percent.
Advantages of recycling
Cynthia Koehler, who will attend the summit as executive director of WaterNow, a nonprofit that works on reducing urban water use, said reusing gray water is critical because half of all household water is used outside. She called gray water recycling a “two-fer” that reduces a home’s intake of water and helps maintain some level of landscaping, which is environmentally preferable to covering everything with pavement.
Showcased projects will range far beyond gray water. Ceres, a water nonprofit that opened an office in San Francisco last year, will also announce a “water climate bonds standard” to provide scientific guidelines that can help investors evaluate the credibility of “green” water bonds. Kirsten James, Ceres’ senior manager for California policy and partnerships, said the San Francisco Public Utilities Commission will be the first to issue a bond under the new standard for storm-water capture and wastewater treatment.
At the summit Tuesday, Stanford University and Aqua Geo Frameworks will release maps made from sensor-equipped helicopters that collect data on alluvial sands in the San Joaquin Valley to help farmers know when to pump or when to refill aquifers. The UC Water Security and Sustainability Research Initiative will unveil a system that combines conventional groundwater data with modeling tools to create a groundwater accounting system that water managers will be able to use by next year.
And NASA’s Jet Propulsion Laboratory at the California Institute of Technology will commit to elevate its Western States water modeling project to a high priority spaceflight mission, providing detailed information on snow, surface water in rivers and reservoirs, soil moisture and groundwater.
Peter Gleick, co-founder of the Pacific Institute, an Oakland nonprofit that works on water issues, said the efforts to improve water use, including everything from federal data collection to corporate sustainability planning, lag far behind attention to energy use and carbon emissions.
“It’s been a long time since there’s been any executive-level attention to water issues in the U.S.,” said Gleick, who will attend the summit. “We’re incredibly bad at collecting critically important data,” citing the collection of national water data once every five years as just one example.
Corporate stewardship programs to make supply chains more sustainable when it comes to water use are just beginning.
“That’s a critical piece of the puzzle,” Gleick said, “but it’s a very big puzzle.”