South Park resident Candace Vanderhoff installs intricate greywater systems to support sustainability
By Bonnie Nicholls | SDUN Reporter
When Candace Vanderhoff discovered in 2008 that San Diego imports 90 percent of its water and no one had a water conservation business in the region, she thought, “I have to figure this out, and I have to start a business. It’s too common sense.”

As the owner of Rain Thanks & Greywater, Vanderhoff, who has a master’s in architecture, installs systems that divert domestic greywater — untreated wastewater from showers, washing machines and bathroom sinks — to gardens. She also designs rainwater-harvesting systems, which capture rainwater in tanks, cisterns and underground storage containers.
Vanderhoff said the average American uses 150 gallons of water a day. In Southern California, half the water used by residents goes to irrigate landscapes.
“We have an insane lifestyle consuming the planet,” she said. “It seems crazy and irresponsible for us to think the planet was made just for us.”
When Vanderhoff installs a greywater system, she first assesses the property to check the plumbing, the slope of the property and where to route the irrigation. California code does not require a construction permit to install a laundry greywater system, although the system must follow regulatory design standards. All other greywater system installations require a permit.
Once Vanderhoff completes an assessment and gets signoff from the homeowner, she works with a plumber to divert the wastewater to outside of the home. She then sets up the PVC piping that routes the greywater to a “bioswale” or trench, a mulch basin or drip irrigation that waters the garden. For some properties, she will also install a filtration system that has a series of filters that remove lint, hair and other impurities from the greywater.
Homeowners can use greywater to irrigate their fruit trees, ornamental trees, shrubs and lawns, but not their vegetable gardens that have root vegetables or vegetables that touch the ground.
Women make up the majority of Vanderhoff’s customers, because “they have a holistic view of their households,” she said. “They can see that it’s wasteful to take a shower and let the greywater go to the ocean. Often they’re gardeners. Gardeners are a big part of it.”
Not surprisingly, Vanderhoff practices what she preaches.

At her own house, which sits on a large property with land reaching down to a canyon in South Park, she installed one greywater system to irrigate her fruit trees, berry bushes and perennial herbs, and another system that goes to a constructed wetland. She also collects rainwater in six tanks. The two largest hold 400 and 300 gallons each, while two others hold 75 each, and two smaller ones hold 50 each.
Vanderhoff learned her trade from Greywater Action, an organization started by a group of women in Oakland, Calif. who became “the leaders in the greywater movement,” she said, and she got her Green Plumbers Training for water professionals. Since then, she has installed systems in San Diego County on properties ranging from 1,100-square-foot houses to $3 million estates, including several in Uptown.
The biggest challenge to starting her own business was that she had never done it before. “But I had read Entrepreneur Magazine for 30 years, so was I super excited,” Vanderhoff said. “I love it.”
The road leading to sustainable living started long before Vanderhoff settled in California. She once worked as a research fellow studying indigenous architecture in Australia and New Zealand, and as a volunteer teacher at the Pohnpei Agriculture & Trade School and the Community College of Micronesia.
Her first job after receiving her master’s in architecture was researching green building materials for an architect in San Diego, and she then managed an Urban Youth Corps program with local artist James Hubbell, building projects in nature reserves. After Hurricane Katrina hit, she worked with a contractor who made modular green homes for victims displaced by the natural disaster.
“My career has always been related to building, and when I found green building, it gave me a responsible way to think of building on our finite planet,” she said.

It is something she still uses, not only in greywater systems, but also in construction on her own property. A longtime advocate of simple, green living, she has a tiny house in her backyard that she built for an exhibition at the Del Mar Fair. Measuring 8 feet by 8 feet, it’s a prefab modular house powered by solar energy and resistant to insects and rot. It’s been featured on TV, and she recently got a call from someone interested in seeing the house as a possible solution for homelessness.
She is also building a small structure on the canyon portion of her property, using earth and a small amount of cement, to show alternative construction methods. And Vanderhoff also holds two certificates in permaculture, a system that mimics the natural environment to ensure human activity, whether it’s construction or agriculture, is sustainable and eco-friendly.
“I guess I have the responsibility chip,” she said. “Is it a blessing or a curse? I’m not sure. But it is my path.”
For more information about Rain Thanks or to contact Candace Vanderhoff, visit rainthanks.com or call 619-807-9193.
Hopefully someday soon we will all be required to use greywater for our gardens. Fascinating topic. Excellent article.
Hi, Celia. I just read that Chula Vista may require that all new construction have greywater systems installed. Let’s hope that goes through.
I wish we could use rainwater collection methods here in Colorado. Id save so much money when it comes to watering my huge Garden..