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Tiburon: The lush lawn and drought-tolerant phormiums are irrigated with gray water.

Mill Valley: The gabion retaining wall funnels water into the garden.

Sausalito: Tucked into a lush hillside lot, the house lies above terraced gardens and an orchard.

Bernal Heights: The exposed pipes in the yard distribute gray water to the garden from the shower drainpipe, which is in the garage. Joshua, the homeowner, says he hasn't had to water the garden once since the system was installed.

Berkeley: From the courtyard, the cisterns are visible behind the slatted wood screen at the bottom right corner of the house.

The trickle-up Effect

Rain catchment is the new buzzword in green home design, and gray water the new gold. Five homes that don't let a drop of precipitation (or bath suds or laundry water) go to waste.

Long before gas hit the $4-a-gallon mark, the most serious environ­mental­ists around here were already driving Priuses. Similarly, long before the skies dried up this winter, leading to a rainy season about 20 percent off the norm, the most eco-conscious homeowners were harvesting rainwater to take care of their lawns—but many were doing it illegally. Until the CalGreen Code went into effect last year—it’s the first statewide green-building code in the country—few regulations existed in the Bay Area for either rain catchment or gray water systems (the latter let you reuse water from bathtubs or washing machines). Anyone who wanted to store rainwater or redirect dirty water to the daffodils pretty much had to do so under the radar of the building inspectors—or subject themselves to a frustrating, and often unsuccessful, permitting process. But now, guerrilla tactics are no longer required, and more and more homeowners are jumping on board. The result is a flood of innovation that’s making these systems the next big green thing since solar panels. In San Francisco, you can now get a permit rebate for using gray water on your lawn. Oakland is offering free rain barrels until the end of the year, and sales of products like Rainwater HOG, a modular system of storage tanks, are up. Plus, organizations like Oakland-based Greywater Action are offering workshops on how to retrofit your home with these innovations yourself. Below, we walk you through the vanguard of water conservation in two beautiful new homes in Berkeley and Tiburon, a sleek Mill Valley spec house, a Sausalito cliff hugger, and a cozy Bernal Heights row house—and offer tips on how to become an insta-rainmaker yourself.

 

Case Study 1:  
Bayside Water Miser

TIBURON:  Here, where the average sticker price for a home is $3 million, residents can generally afford to build almost anything they want—and go for the best. So when a couple who were building a sustainable house (and hoping for a LEED Gold certification) decided to spring for state-of-the-art rainwater catchment and gray water systems, one of their first phone calls was to Oakland-based WaterSprout, one of the most sought-after rainwater designers and installers in the region. Their portfolio includes a system on Alcatraz that waters the restored historic gardens and one in the buildings at Crissy Field that’s used for flushing toilets.

     For this house, relatively modest at 2,500 square feet, WaterSprout founder John Russell installed a system that collects rain runoff from the roof and drains it into a 3,000-gallon underground storage tank. The water is then filtered and disinfected before being used in the home’s three toilets and washing machine. (Filtration improves water quality and removes sediment but is not required by the state.)

     Gray water from sinks (except the kitchen sink, which harbors bacteria-prone bits of food), showers, and the washing machine drains into a buried 200-gallon tank. This water is filtered, too, before it reaches the garden, which is landscaped with mostly drought-tolerant plants and a meadow of native fescue.

     Because this house was built from the ground up, installing such systems was comparatively easy—no walls had to be broken open to get to pipes. Now, for the homeowners, taking a long, hot bath is no longer a guilty pleasure.
 


Case Study 2:
State-of-the-art Reuse

MILL VALLEY:  Spec houses aren’t generally equipped with cutting-edge green designs, which is what makes Sausalito architect Geoffrey Butler’s homes so unusual. He built his sleek $2.9 million Mill Valley spec house with systems worthy of a LEED Platinum certification, the highest level awarded by the U.S. Green Building Council.

     The four-bedroom, three-and-a-half bathroom home uses a modular water-storage tank system, by Rainwater HOG, an Australian company now headquartered in Corte Madera. When it rains, 15 50-gallon HOGs lined up vertically behind the garage collect up to 750 gallons of water, which is then used to flush the low-flow toilets in the home’s bathrooms. (If there’s not much rain, a float switch registers that the tanks are empty and automatically turns to municipal water.)

     Water from the outdoor shower, the master bath shower, and the bathtub, meanwhile, is collected in four 50-gallon HOGs that lie hidden beneath the front deck. Since the state requires that gray water not be kept for more than 24 hours (if it’s left out longer, it can start to smell), the system pumps itself dry every day, nourishing a small lawn. The rest of the landscaping—drought-tolerant native plants—survives on water-miserly drip irrigation.

     In addition to relying less on water from Marin County’s already stressed reservoirs—for the first time in 20 years, the Marin water district has had to tap Phoenix Lake, near Ross—such systems will save homeowners some dough. In a house that accommodates five occupants, municipal water for toilet flushing would be required only four to five months a year.

 

 

 

Case Study 3:
Double-Duty Rainwater

SAUSALITO:  Sometimes it takes just one daring homeowner to get the ball rolling—and in this case, it was a retired international businessman whose Sausalito house became the first in the state to get approval for using rainwater inside. The man already had a similar system at his house in Germany (not to mention a water-saving eco-development in South Africa and an off-the-grid home in Ireland). When he approached 450 Architects of San Francisco about building in Sausalito, he had requests typical of such idiosyncratic clients. He wanted his new house to be both Zen and Mediterranean and to have a rainwater catchment system that would not only irrigate the gardens but also wash clothes and flush toilets.

     “We had never done anything like this before,” says David Bushnell, a principal architect with the firm. Apparently, neither had anyone else in Sausalito, Marin County, or the entire state—at least legally. (The permitting process for the house began some six years before the CalGreen code went into effect, last year.) Officials at Marin’s Community Development Agency were worried that the rainwater, which can contain bacteria and chemicals, would contaminate the city’s water via the home’s plumbing. So the architects brought in civil engineers, who provided evidence that the system wouldn’t back up.

     In the end, the homeowner got what he wanted. The resulting 2,670-square-foot house has a roof designed like a parasol that creates shade and collects rainwater. Then, the rainwater is carried by gutters into a 6,000-gallon cistern, which pumps the water up into the house for clothes washing and toilet flushing. Cistern water also irrigates an orchard and terraced gardens below.
 

Case Study 4: 
Urban Green Thumbers

BERNAL HEIGHTS:  If ever there was a perfect couple to inaugurate the first official gray water system in San Francisco, it would be Joshua Lowe and his wife, Carleigh. He’s an architect who’s been working in green architecture since graduating from college in 2003; she’s a former editor at Dwell, where sustainability is a major part of the message. Together they live in a formerly 450-square-foot Bernal Heights house that they expanded to 680 square feet—still modest by any standard. So after the state green-building code was written and the San Francisco Public Utilities Commission was looking for a simple house with a simple plumbing system to serve as an example of gray water recycling, the Lowes were happy to volunteer.

     The Lowe house was a perfect fit. In a neighborhood built for shipyard workers in the 1920s, it’s a modest wooden A-frame, so there weren’t a lot of pipes buried deep inside the crawl space. The drainpipe for the bathroom shower was particularly accessible—exposed in the garage. Once he got a permit, all Joshua had to do was cut out a piece of the pipe and put in a valve that redirects used shower water to the 200-square-foot front-yard garden. And because the shower is above the garden, gravity moves the water into a drip irrigation system, precluding the need for electrical power. The whole process was so easy that they did it themselves for $500, including the permit.

     Normally the couple would have gone for a drought-tolerant garden, but since the shower produces up to 40 gallons a day, they had to select thirstier varieties like ferns and palms. And they discovered in their research that their plants are finicky: They don’t like bath products with sodium. As a result, the couple had to switch out some of their soaps and shampoos. (See “When Your Ferns Hate Your Bar Soap,” page 72.)

     But they’re thrilled with the whole arrangement. “It sounds kind of dorky, but we now have a different relationship with the shower,” Joshua says. “You know it’s watering plants. It really changes your perception and your relationship to the environment.”
 

Case Study 5:
Doing as the Romans Did

BERKELEY:  Their aqueducts get all the attention, but the Romans also came up with one of the world’s first rainwater catchment systems: the impluvium. This was a sunken part of a home’s central courtyard that collected rainwater, which poured off specially designed slanted roofs. “The harvesting of water was
as important as the harvesting of fields,” says Oakland architect Geoffrey Holton, who is so passionate about water conservation that he installed both rainwater and gray water systems in his own Berkeley house before the city had any guidelines in place.

     Inspired by the impluvium, Holton suggested that his clients Alan Hodges, an environmental engineer, and Christine Lorang, a computer software engineer, create a similar courtyard model in their new home in Berkeley. Rainwater would be funneled through a single downspout into eight cisterns tucked under the house, and then used to irrigate the gardens. To sell his idea, Holton showed the couple images of rainwater catchment in other parts of the world—a strategy that Hodges says won over Lorang. “What helped convince my wife was that it wasn’t just some crazy new idea that hadn’t been done before,” he says. “Geoffrey showed us pictures from Australia, where the volume of rainwater catchment tanks is almost the same as the volume of the house.”

     The resulting home, a dramatic 3,000-square-foot structure in the Berkeley hills, with solar hot water and other sustainable attributes, became the first in the city to receive a permit for residential rainwater catchment. As for the home­owners, using rainwater to irrigate their vegetable garden and drought-tolerant land­scaping couldn’t be easier. “We don’t have to do anything,” says Hodges, “except turn it off when it rains for a week.”