Graywater Conservation Workshop Draws Overflow Crowd at Community House

By Flavia Potenza, Topanga Messenger

Crowding into the Topanga Community House, 125 Topanga residents, already savvy about graywater systems, came to learn more from a panel of experts. By the end of the evening their heads would be exploding with a torrent of information about graywater use past and present.

The workshop was hosted by L.A. County Supervisor Shiela Kuehl represented by Field Deputy Timothy Lippman, the Topanga Town Council (TCTC) and the Topanga Creek Watershed Committee (TCWC), who brought together Laura Allen, founder of Greywater Action (; Carlos Borja, Chief Environmental Health Specialist, County Department of Public Health; Dave Rydman, Civil Engineer with County Public Works, Waterworks District; and Kaveh Razavi, Sr. Mechanical Engineer with County Public Works Building and Safety.

Allen began with a presentation, “Drought-proof our Landscape with Greywater,” noting that 50 percent of our potable (drinkable) water goes into landscaping.

“Why not, instead,” she asked, “take the water from our showers and clotheswashers and redirect that to our landscapes? A properly designed graywater system can save a lot of water.”

And money. Reusing our once-used water a second time as graywater, can result in a 16 to 40 percent reduction in water use.

What is Graywater? Water from clotheswashers, sinks, baths and showers that can be redirected to irrigate larger plants, such as trees, bushes, vines, and larger annuals and perennials. It is not potable and should not be used to water lawns, small plants, root vegetables or vegetables that we consume.

What is Blackwater? Water that is disposed of through a septic or sewer line, e.g. toilets, dishwashers and kitchen sinks. Currently kitchen sink water is not considered graywater in California and is difficult to legally reuse. Because people often wash chicken and other meats that may contain bacteria and dump grease down the drain, it is considered a health hazard.


Is graywater legal? Yes, graywater is legal now and regulated by Chapter 16 of the Plumbing Code.

Allen gave a brief history of the legality of graywater. Before 2009, it was not possible to install a legal system but there were still 1.6 million illegal systems in California. After 2009, It became legal to install several types of systems legally, some that don’t require a permit.

Graywater can be used for outdoor irrigation and to flush toilets but toilet systems require filtration, disinfection and frequent maintenance and it’s difficult to obtain permits for them.

A simple system that many Topangans may have used over the years is what Allen calls “Laundry to Landscape,” a washing machine system that doesn’t alter the plumbing and doesn’t require a permit as long as basic guidelines are followed.

“The simplest system, however” Allen said, “is the bucket in your shower. Collect the water, a couple of gallons, and put it on your thirsty plants.”

Her book, “The Water Wise Home: How to Conserve, Capture, and Reuse Water in Your Home and Landscape,” is a comprehensive how-to design and build residential graywater systems that includes step-by-step construction details.

Save the Date: Allen will be conducting a hands-on workshop in Topanga on Saturday, September 5.


Carlos Borja with the Department of Public Health, addressed Alternative Water Systems and has seen these systems develop over the years through environmental and political changes, impetus from grass roots organizers and “the drought, the drought, the drought.”

Public Health’s role is protecting the public against misuse of alternate water systems that can expose people to infectious agents from unknown water sources, chemical exposure and cross-connections to the drinking water supply.

Alternate water systems are rainwater catchment; recycled water (under Title 22 standards); Graywater; Stormwater; Urban run-off; and industrical sources/reclaimed water.

By 2030, Borja said, “Santa Monica City’s goal is that all run-off will be used on site and won’t run into the bay any more.

Giving a nod to Allen, he said to the audience, “If you follow Laura’s suggestions, you’ll have no problem getting approval.”

Throughout the evening, Borja noted that public health projects “need to have proponents come to us and include their design ideas in our projects. We want to be more accessible.”


“Graywater is simple to use,” Dave Rydman, Civil Engineer with L. A. County Waterworks District, began. “We are in the first month of the governor’s restrictions. Topanga is required to reduce water use by 36 percent. We see double digits where Topanga and Malibu reached 24 percent. A lot of that is being led by residents of Topanga.

“Share your success stories with us on #DroughtDiet, #MalibuDroughtDiet, #lacowaterworks and Nextdoor Topanga.” For those who don’t Tweet, go to;

“I like Laura’s bucket idea,” Rydman said. “My wife and I save about $6 a billing cycle. For us, that’s the equivalent of two double lattes, so we have “latte dates.” He also suggested people check to see if their toilets leak. “Check the flapper,” he advised. “If it has a white ring around it, it’s leaking water. Go down to Franklin’s Hardware and buy a new one.”

Dick Sherman suggested putting a few drops of red dye in your toilet tank.

“If you see it in the bowl, it’s leaking,” he said.

Rydman also urged people to “stop irrigating the grass. We had 350 million rebates to customers who are pulling out their lawns and replacing them with native and drought tolerant landscaping.” The program is no longer available due to the high response rate.


Providing an overview of the greywater systems that the County oversees is a complexity of details about types, designs, codes and permits that fell to the expertise of Sr. Mechanical Engineer for Building and Safety, Kaveh Razavi.

“Graywater systems have been part of the code since 1995,” he said. “When [L.A.] County adopted its ordinance then the state followed and added it to their code.”

He noted that there are three types of graywater systems: a single washing machine that people can do themselves; a simple system with a capacity of 250 gallons or less that you can do yourself for a few hundred dollars or hire someone who will comply with the plumbing code; and a complex system for more than 250 gallons that is required to be installed by a certified professional and can cost thousands of dollars.

A question and answer period followed the presentation with a number of smart questions from people familiar with graywater systems. A breakout session where people could speak one-on-one with the panelists followed and, even as the hour grew late, people lingered and absorbed even more information.

“Graywater isn’t the only system,” said Borja. “Now we just need rain.”

For more information: