Every time Anne Smith washes her kids’ grass-stained sports uniforms, her agapanthus gets watered too. It’s a time-saving, water-conserving trick that may one day become commonplace as more and more people discover the benefits of recycling the household “graywater.”
That dirty water laden with detergent, hair and other unmentionable cooties that drain from our washing machines, bathroom sinks and showers classifies as graywater, and it makes up more than half the average household’s water waste. Since 1928, graywater has been flushed into city sewers along with the “blackwater” that drains from toilets and kitchen sinks, sent to a water treatment center on Bay Street and later expelled into the ocean via Monterey Bay. But with droughts, heightened awareness of water scarcity and a new emphasis on conservation, the fate of gray wastewater is beginning to change. And Santa Cruz, not surprisingly, is at the forefront of a growing movement to legally divert household graywater away from the sewer system and into the soil, where it can provide moisture for trees and other plants and recharge long-depleted water tables.
In January, the California Building Standards Commission adopted a new plumbing code legalizing graywater reuse in residential buildings, a breakthrough that gives residents the go-ahead to rig up their own systems. Proponents say it can save money in the long run, relieve overstressed septic systems and conserve the life-giving element. Most importantly, perhaps, it can help change the way people think about their water use.
“Instead of calling it wastewater and shipping it downstream, graywater goes with the idea that we all live downstream,” says Ken Foster of Terra Nova Ecological Landscaping, a member of the Central Coast Graywater Alliance. “In nature there is no such thing as waste. One thing’s waste is another’s food. Graywater reuse transforms our concept of waste.”
Unlike blackwater, graywater is safe and abundant enough to use for irrigating landscape and certain types of garden plants (it’s not recommended for root crops, for example). If done right, the benefits can be manifold.
For the Smith family, a laundry-to-landscape system that directs laundry water around the garden via a pipe connected to their washing machine provided an invaluable solution to the nightmares caused by an overstressed septic system. Diverting thousands of gallons monthly from a saturated leach field in their case has meant a savings of $30,000-$40,000, the cost of hooking up to the city septic system or installing a new leach field.
Thanks to the recent legalization of graywater diversion systems, landscapers and conservationists throughout Santa Cruz are preparing workshops and classes to teach folks how to install laundry-to-landscape systems that are up to code, and the Soquel Creek Water District has recently approved a $75 rebate for laundry-to-landscape systems, effective this July.
Mother Earth Knows Best
All laundry-to-landscape systems, whether simple or complex, rely on one fundamental component: the soil’s natural “food web.” The microbes and insects that live in soil act as a biological filtration community, breaking down and using as fuel the microscopic bacteria, potential pathogens, lint and hair that come out in the wash water. Conveniently, these fungal microbes and insects that love to eat nasty things thrive in wood chip mulch, a garden’s best friend.
Although their powers are great, these microbes are not skilled at breaking down chemicals, so laundry-to-landscape users should refrain from washing their socks in Clorox and should use only ecologically safe detergents. Don’t let your disappointing experiment with all-natural plant-derived antiperspirant deter you; there are many graywater-friendly detergents on the market with effective cleaning ingredients like papaya enzyme. Anne Smith vouches for them: according to her, they “work great.”
Graywater has not been granted above-ground rights, and legally it must never see the light of day. At least two inches of wood chip or other mulch is recommended to cover the areas where graywater is expelled into the soil. It is also unsanitary to allow graywater to pool on the ground’s surface or to run it through a sprinkler system to spray the leaves of your salad greens, since these methods don’t allow proper filtration. Plus, that would just be nasty. And that’s not what graywater’s about.
The Options
The most basic laundry-to-landscape model is cheap and easy. According to Sherry Bryan of EcoAction and the California Graywater Alliance, the cost of a simple system is between $100 and $200, and it’s simple enough that even the mechanically impaired among us could learn how to install it. This system involves a three-way valve that connects an external pipe to the washing machine. The washing machine’s pump then propels the water through the pipe, which can be perforated in certain areas—say, under the rose bushes or apple tree.
The three-way valve is crucial here. Did your space cadet roommate mistake Comet for your ecofriendly detergent again? Flip the valve from “landscape” to “sewer” and the roots of your prized fig tree will be spared the caustic chemical burns. The graywater flow should also be redirected to the sewer in times of heavy rain to prevent flooding the garden.
According to Bryan, the simplest branch drain laundry-to-landscape system can save almost 4,000 gallons of water a month used for landscape purposes during the irrigation season (May through October). Watering your plants with perfectly good drinking water that has gone through a costly purification process seems crazy when graywater is an optional source—almost as absurd as flushing your waste with the same purified drinking water.
More elaborate laundry-to-landscape irrigation systems like the one that keeps Smith’s agapanthus satiated have a materials cost of around $400-$500. Golden Love of Love’s Gardens is the mastermind behind Smith’s irrigation system. The garden is set around a bocci ball court, with an expanse of black piping running its length beneath the mulch, and with 28 release valves that can be opened or closed to release the water.
The most elaborate systems, incorporating bathroom sinks and showers to the graywater flow, require a permit and an approved backflow valve to prevent graywater from flowing back into the sink or shower whence it came.
A Case-by-Case Solution
Laundry-to-landscape systems are a great start to graywater reuse, but they’re not the end-all solution to water scarcity in Santa Cruz.
Toby Goddard, the city’s water conservation manager, encourages citizens to explore the options that the state’s liberalized use of graywater may present in their own yards but to remember that it is one of many measures a resident can take to conserve water. Reducing yard size, using low-volume sprinkler nozzles and weather-based irrigation systems and planting more shade trees are other methods Goddard lists to cut down on landscape water usage.
After all, as Sherry Bryan of Ecology Action says, the point is to reduce along with reusing and recycling.
“Just like you would reduce your overall energy consumption before installing solar panels,” she says, “you should reduce your overall water consumption before pumping all your graywater into your landscape.”
The following organizations can help first-timers get their graywater systems up and running.
Central Coast Graywater Alliance
www.ecoact.org/Programs/Pollution_Prevention/Graywater/index.htm
A good starting point, this site explains the ins and outs of installing a graywater system, including permitting requirements.
Love’s Gardens
http://www.lovesgardens.com/
Contact information for May 15 graywater workshop (sliding scale $45-$75). 831.471.9100.
Monterey Bay Green Gardener Program
http://www.green-gardener.org/GreenGardenerAdultSchoolClasses.htm
Contains links to upcoming classes on graywater training at Cabrillo College, June 9-July 7. 831.786.2160.
Santa Cruz Green Business Network
www.meetup.com/Santa-Cruz-Green-business-network/
The Santa Cruz Green Business Network, headed by Ken Foster, is a clearinghouse for local experts in green projects such as graywater systems.
