Dec 23, 2006

Gray water project saves water, helps bay

By Doug Oakley / Daily News Staff Writer

A group of Berkeley environmental activists is working on a project to divert used household water from the sewer system - and ultimately the San Francisco Bay.

The activists could become the first group in the state to get a permit for combining a "gray water" system with a constructed wetland in their backyard.

The EcoHouse group has been working on the system for two years and is waiting for final approval from the city of Berkeley. The system takes shower, bathroom sink and laundry water and runs it through a backyard gravel bed topped by water-loving plants and then into mulch-filled trenches, where it eventually seeps back into the groundwater.

EcoHouse board member Babak Tondre believes the EcoHouse is the first residential project in the state to combine a gray water system with a constructed wetland - and get approved under the California building code.

The idea behind the demonstration project is to provide a template for ecology-minded homeowners who want to reuse water, and get it approved by local authorities. The gray water system not only saves valuable treated drinking water from being wasted on outdoor plants, but it takes the burden off sewer treatment plants that ultimately put their water into the Bay.

"We wanted to see how the average homeowner could do this and get it approved," Tondre said. "So now we have a template, and anyone who comes to our workshops can use it."

Tondre admitted that there are no economic incentives from local or state authorities to refund the $3,000 to $8,000 a homeowner would have to spend on the system. The price would vary depending on how much outside help a homeowner would get to construct the system.

"It doesn't sell itself on the water savings," Tondre said. "What it really sells itself on is the ethics of knowing where water is going and that fresh water is scarce and getting more so. Water is the root of all life, and once homeowners see that, they get in tune with the water cycle and see how important it is to reuse it. You don't need to water your garden with drinking-quality water."

Joan MacQuarrie, Berkeley's building official in charge of permitting, said the California building code allows residential gray water systems, and it's up to local authorities to approve them.

"The system has to be designed by an engineer and it can't have standing water," MacQuarrie said. "Water is certainly an issue in California. I would say there is a move to see what we can do to recycle and reuse it safely and that's what these gray water systems do."

MacQuarrie said residents have tried to get gray water systems passed in Berkeley, but none have succeeded.

"As far as I know (the EcoHouse) is the first one to come through the permit system," MacQuarrie said. "Initially it's a lot of work for them and us, because the code requirements are stiff and we've been through a lot of rounds of the plan checks. Once we do it a few times, it gets easier."

Paul Johnsen, a gardener who lives at the EcoHouse, said he hopes the project gets others interested in residential gray water systems.

"This is the precedent that hopefully will encourage people to divert water from their septic systems and help to keep the Bay cleaner and reduce the amount of potable water used in backyards," Johnsen said.

E-mail Doug Oakley at doakley@ebdailynews.com.