Palo Alto resident Sven Thesen’s garden plants are about to get a free, renewable source of water, just in time for spring.
Thesen’s house, on Stanford Avenue, made a splash last fall when he and his wife invited locals, including Palo Alto Mayor Sid Espinosa, to his ultra-green home to show off the building’s cutting-edge eco-designs.
Since then, he’s been working with the City of Palo Alto’s Building Services department to build out a graywater system that allows him to save water from his kitchen sink and use it in his garden.
To do that, the water has to be filtered. Thesen’s design calls for a large tank full of redwood chips that he salvaged from a friend’s demolition. Microbes living on the wood chips break down the water to a level safe for irrigation.
The State of California doesn’t make it easy to install such a system, however. Unless you get a special variance, the state’s plumbing code doesn’t allow for it. So that’s exactly what Thesen did.
“Because it is a pilot, and experimental, they gave us the permit,” said Thesen.
Once the system is installed, it will divert about eight to 16 gallons of water per day from the Water Treatment Plant to a special filter buried in his back yard.
Thesen says these kinds of water conservation systems are long overdue for a state trying to meet aggressive carbon reduction and energy and water conservation goals.
“California uses 20 percent of its total energy supply on water shipments, moving water around the state,” he said. “If we can reduce our water need, we can reduce our energy needs, which means fewer power plants, fewer transmission lines, which means energy costs go down for everybody.”
Thesen said that for Palo Alto to approve the design, he had to promise a number of improvements, including a high-level water alarm which will sound if, for example, he left the sink running and it started flooding his yard.
If local homeowners began widespread adoption of this kind of technology, Thesen says it could help the City meet its aggressive carbon reduction goals while reducing the impact on the water treatment plant. For it to be rolled out to the masses, though, Thesen’s pilot test has to be a success.
“The city is saying hey, we are promoting people who want to put in place pilot systems,” said Thesen. “We recognize the benefits, we will not say no to putting in systems like this, just give us the data.”