Post-Paris, Can Los Angeles Become Water Self-Sufficient?

Rain garden
Rain gardens installed in back yard helps infiltrate water back into the ground. Photo courtesy Tree People

“The historic climate agreement adopted on Saturday in Paris breaks new ground. I got chills watching the room erupt in applause, hugs, and tears, as it was finalized . . . when I stood in Paris at City Hall with Mayor Garcetti and 445 other mayors on December 4 — a better, greener, future felt possible.”

That was LA Chief Sustainability Officer Matt Petersen, responding to the accord reached in Paris at the COP21 talks this past weekend. But as he also pointed out, “this is just the beginning. We must redouble our efforts to keep up the tremendous momentum.”

Why does this matter so much to Los Angeles? Because not only do cities cause the bulk of emissions, but they are also vulnerable to the impacts of climate change.

In California that is expected to mean more and longer periods of extreme heat, extended fire seasons, shorter but more intense periods of rainfall, and “then the impact of a worsening drought on our water reserves,” says Petersen, adding:

“Not only did we have the worst, lowest snowpack in decades, we know that going forward even with the wet El Nino we may not have the snowpack we need and we’re certainly not going to be solving the drought even with a wet El Niño season so we need to continue to conserve and really have a long term solution so we get to 50 percent of local water supply here in L.A.”

50 Percent of Local Water Supply here in L.A? Really?

50 percent of local water supply here in LA? Or, in Santa Monica, 100 percent water-sufficiency by 2020 is the goal. These seem like wildly ambitious benchmarks when you think how much of our water is piped in from the Colorado River and snowmelt from Northern California.

But it turns out LA is doing its bit for water management in ways that are invisible to most of us — and making steps towards moving away from the 20th century paradigm of massive infrastructure projects.

So how do they plan to do so? Simply, by treating the entire region as a water catchment area, from retrofitting the LA River through incorporating rain capture features (barrels, cisterns, rain gardens) in the design of all private homes.

Those are longterm goals. But cities are already at work making changes to the cityscape that reflect a profound change in the region’s philosophy of water management.

Read on for some of the solutions, or hear all about them on this broadcast of DnA, above, with Matt Petersen, Andy Lipkis, Deborah Weintraub, Gary Lee More, Marty Adams, Hank Koning, Amy Levine and Art Castro.

SM sign on side
“Collected Rainwater Below Here” indicates the presence of a water cistern, gathering rainwater that falls on the Pico Library, behind. Photo by Avishay Artsy.

Public Education in Santa Monica

At Virginia Park in Santa Monica, the city has spray-painted a large sign onto the ground in front of the new Pico Library. It features a dotted line marking the presence of a water cistern buried underground and the words “Collected Rainwater Below Here.”

Why indicate the presence of this invisible cistern. Dean Kubani, Manager of the Office of Sustainability and the Environment for the City of Santa Monica, explains:

“What we’re trying to do is educate people that water is important and we know now in Southern California with the drought that we’ve got to use water very wisely… This is a library, this is where people come to learn things and they also need to learn where their water comes from and that twelve thousand gallons are under their feet right here that they’re using to offset otherwise drinking water for flushing toilets and things.”

How the cistern works at Pico Library, designed by Koning Eizenberg architects.
How the cistern works at Pico Library, designed by Koning Eizenberg architects.

Yes, that’s right, the rainwater is collected in the cistern and is cleaned up and used to flush the library’s toilets. Seems like a logical idea.

But not everyone at the city initially embraced the idea, recalls the architect of the Pico Library, Hank Koning, who told DnA that people were concerned that somebody would drink from the toilet. 

So the health department said to us we should put signs up that this is not potable water. And I said, ‘who drinks from a toilet?’ and they said ‘dogs do.’ And my response was, ‘well, dogs are out of luck because they can’t read.'”

Koning happens to come from Australia, which leads the world in water-capture since a devastating drought ten years ago. It’s LA’s turn now, says Dean Kubani, and it’s going to take public education to bring about a change in habit. Furthermore, he says, “low-tech is key.”

You won’t hear desalination mentioned in Santa Monica. But the city is expanding its current water treatment plant; it has plans for building a water cistern and for digging a “brackish” well, both below the pier. Planners are also considering tapping into the sewage pipes and capturing that liquid and cleaning and processing it for irrigation and other uses.

A smart water cistern in North Hollywood. Image courtesy of TreePeople.
A smart water cistern in the yard of a home in North Hollywood. Image courtesy of TreePeople.

LA Storm Catcher

The City of LA is also thinking about water cisterns, and on the very same day last month that Santa Monica staff were painting their sign in front of Pico Library, the Mayor of LA went to a private home in North Hollywood and unveiled a new pilot program of so-called “smart” water cisterns called LA Storm Catcher.

This is a city- and county-led pilot program in which cisterns of hundreds or thousands of gallons are being installed in the yards of up to 10 houses. They have sensors that monitor storm predictions enabling water to be siphoned back into the ground through “rain gardens” making more space for fresh rainwater.

In the past this rainwater would have been directed to storm drains and into the flood control channels that would rush it out to sea.

Andy Lipkis, second from right, and Mayor Eric Garcetti, center, unveil LA Storm Catcher, November 4, 2015
Andy Lipkis, second from right, and Mayor Eric Garcetti, center, unveil LA Storm Catcher, November 4, 2015

LA Stormcatcher was created in collaboration with the ​organization TreePeople, founded by Andy Lipkis, who told DnA that the smart cisterns represent a new approach to water management in LA:

“The old infrastructure system was built with people being the problem. The polluters and the victims. This one takes us to the new day where we are all participants, where we’re all managers of the water, where we’re incentivized to conserve, where we’re given feedback information so we can help manage it. But the smart cistern is right at the center of that. Because everybody can be involved in managing that water and conserving it.”

The results of the Stormcatcher pilot program will be analyzed to learn how these systems could be deployed at scale​ across LA.

Swales during rain 110515
Swales in the parking lot of the Los Angeles zoo during rain in November 2015.

LA Sidewalks and Parking Lots Redesigned for Water Capture

You might have noticed that some parking lots and sidewalks on LA city property have what seem to be unkempt landscape borders. These are examples of bioswale, or vegetated swales, which are, explains Deborah Weintraub, Chief Deputy City Engineer, City of Los Angeles, “landscapes that are natural filtration systems for the storm water runoff.”

Bioswale in Pacoima
Bioswale on a street in Sun Valley; photo by Frances Anderton.

There are also paving methods that allow for water to soak in, reduce stormwater runoff and permit stormwater infiltration and, in some areas, can recharge the groundwater (where it is not polluted as in much of San Fernando Valley).

This is known as permeable paving or, more poetically, “thirsty concrete.” Installing “thirsty concrete” is a means to counter the impermeability of most of the region, which is carpeted in dense concrete and asphalt.

LA Zoo Bioswale at Roadway Absorbing Water
LA Zoo Bioswale at Roadway Absorbing Water; photo courtesy City of LA Department of Engineering.

Weintraub urges us to go check out the LA Zoo.

“Really the most stunning examples we’ve done a number of years ago which is the zoo parking lot in front of the main entrance to the zoo where we piloted different permeable surfaces so there’s permeable paving in some of the parking stalls. There’s porous concrete in some of the driveways. And then the whole parking lot is sloped to what are called vegetated swales.”

Tujunga Spreading Grounds
Tujunga Spreading Grounds, photo by Frances Anderton

Tujunga Spreading Grounds

This image may seem uninspiring — a large, arid, unfinished pit. And that’s exactly what it’s meant to be. This is one of the Tujunga Spreading Grounds in Sun Valley, an essential cog in the wheel of efforts to capture and conserve more rainwater in the San Fernando Valley.

Art Castro, civil engineer for DWP, says he and fellow engineers chase floods to figure out good places for rainwater capture.
Art Castro, civil engineer for DWP, says he and fellow engineers chase floods to figure out good places for rainwater capture. Photo by Frances Anderton.

How do the spreading grounds work? When it rains on the San Gabriel Mountains, the rain whooshes down the Tujunga Wash and into a concrete channel. The DWP inflates a rubber dam which stops the flow of water and diverts it into these spreading basins. Now a project to upgrade the spreading grounds is set to begin next spring that will consolidate and deepen the basins, doubling the amount of water that can be captured, cleaned and fed into the water system.

DWP civil engineer Art Castro described the Spreading Grounds as. . .

“. . .a big empty bowl, essentially gravelly soil at the bottom. So it acts like a sponge, any time people put water into it within a couple of days the water will be fully infiltrated into the aquifer.”

Rubber dam, photo by Frances Anderton
Grasses indicate presence of a rubber dam that inflates to redirect rainwater into the spreading grounds, left; photo by Frances Anderton

When rain falls hard on SoCal, Castro and fellow engineers go out into the streets, looking for where water is pooling and backing up, as those indicate possible sites for more water capture.

He says that times have changed for water engineers.

“As engineers in school we were taught to convey stormwater and get it out your sight, out of your facility as soon as possible because it’s generally met as a bad asset to you. Now we see it as a resource. So now we want to capture as much as we can.”

These are just a few of the examples of water capture at a municipal level. There’s is still much to be done, including a massive clean-up of polluted groundwater basins in the San Fernando Valley. Send us images of what you are doing to capture water and we’ll share on this DnA blog.

Siemens system
Siemens water processing technology at the Tujunga Spreading Grounds cleans the captured rainwater and feeds it back into the water system; photo by Frances Anderton.