Community Conservation Solutions is piloting a new analytical tool that not only taps an untapped local water supply — the 969 miles of metropolitan storm drains in Los Angeles — but also has the metrics to earn carbon credits for doing so. “It’s very practical, you just stick your straw in the local water source rather than pumping it into the city from hundreds of miles away,” says the NGO’s director Esther Feldman. The tool helps land and water managers prioritize projects on public lands near stormdrains that use this local water to irrigate and vegetate the urban ecosystem, and to recharge groundwater.

Estuary News

June 2017
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LA Drainage Goes Native

by Ariel Rubissow Okamoto

Citydwellers are accustomed to rain water being whisked down a drain and out of sight. While those who live on the edges of concrete flood control channels may have marveled at an occasional torrent in winter, or dreamed of skateboarding down these dry riverine chutes in summer, the general idea of getting the water away from the people prevails. Esther Feldman thinks otherwise.

“We’re so rich in water-moving infrastructure in our cities and so poor at tapping it where it could do the most good,” says Feldman, director of a nonprofit called Community Conservation Solutions.

This summer, Feldman’s organization is piloting a new analytical tool that not only taps an untapped local water supply –the 969 miles of metropolitan storm drains in Los Angeles — but also has the metrics to earn carbon credits for doing so.

“It’s very practical, you just stick your straw in the local water source rather than pumping it into the city from hundreds of miles away,” says Feldman. The local water can then be used to irrigate and vegetate the urban ecosystem, and to recharge groundwater.

Decades of ups and downs in Sierra snowpack, California’s go-to water supply, capped by five years of drought, continue to inspire big picture thinkers to come up with greater efficiencies, especially in Los Angeles, where 90% of the supply comes from Northern California, the Owens Valley, or the Colorado River. Moving water from north to south and east to west takes energy and produces greenhouse gases. In an era when climate change impacts on water supply are coalescing around deteriorating infrastructure in still growing cities, finding enough water for the future isn’t simple any more. It’s all about sharpening our focus on where the water is and how to use it.

Wet weather runoff in Los Angeles.
Photo courtesy Community Conservation Solutions

In Los Angeles, county public works projects capture enough rainwater to serve the annual needs of 1.5 million residents, but with the right projects, officials think they could double or triple that amount. And it’s not just rainfall that’s whisked out to the Pacific. In the upper Los Angeles River watershed, people hosing down hardscapes, washing cars, and irrigating greenery produce enough dry season runoff (affectionately known as urban slobber) every 48 hours to fill the Rosebowl.

According to the pilot Green Solutions tool, there are many promising spots on public property in the upper Los Angeles River watershed where stormdrains could be tapped to irrigate quiet, leafy, pretty parks and pathways in communities sorely in need of places to stretch legs and push strollers. “With this tool you don’t have to start from scratch and you don’t have to buy land. It tells you what the best projects are to do and in what order,” says Feldman.

When Feldman explained the new Green Solutions tool to me, it took an hour to cover all its bells and whistles. In very basic terms, the tool identifies likely stormwater capture sites on public lands and then prioritizes them based on how close they are to a stormdrain, as well as community need and carbon footprint, among other variables. The process has sorted 453 projects within 500-1500 feet of a stormdrain or flood control channel, and identified 87 of highest priority.

The water and energy use analysis is particularly interesting. Apparently, implementing all 453 projects would generate enough new local water supply, and aquifer recharge, to serve 52,000 homes and replace nine percent of the imported supply used in the watershed. Tapping water already in the local system, meanwhile, would reduce the greenhouse gas emissions associated with long-distance delivery by an amount equivalent to travelling 1 billion vehicle miles.

Making these kinds of metrics available for specific potential park and water projects should help cities, counties, public works agencies, NGOs, and elected officials better decide where to spend their money.

“As funding becomes scarce, it makes no sense to do projects than only achieve one outcome,” says Sean Vargas of VS2 Consulting Inc., consulting engineer on the Green Solutions team. “To do multi-benefit projects, we need to chose and prioritize. The good thing about this tool is you can twist the dial. You can balance environment, money, and people equally as you squeeze the water balloon, or you can favor one at the cost of the other. But no matter what you do, the tool will help you deliver a better project.”

Beauty off the Interstate

Ramona Gardens is high on the tool’s priority list. When we arrived at this 1940s era cinderblock affordable housing development, the first thing I noticed was the sound of greenhouse gases being produced by thousands of combustion engines. Twelve lanes of highway and a rail line barrel past these homes just a few steps away from the bedrooms of 700 children.

“Most families in our community are used to being told this is what you get, and you should be happy about it,” says Lou Calanche, who grew up near the 500-unit housing project in Boyle Heights, one of the three most polluted neighborhoods in California. Calanche now runs a youth leadership and education program called Legacy LA. “Our youth dream about a tree buffer between their homes and the highway to filter the noise and fumes.”

Ramona Garden’s noisy neighbors: Interstate 10 and the metro line. Photo: Tira Okamoto

This summer, local youth working for Legacy will go door-to-door to get residents opinions on plans to improve the long linear strip of space between their homes and the freeway. Right now, this four acre area is punctuated by the hulk of a roofless ruin, some rundown ballcourts, a community garden, and other activity hubs, all of which the Green Solutions team would like to connect with a long “greenway” through a natural park watered by the huge stormdrain underneath.

Greenway is the latest label for a parklike path, often gracing the edges of ugly flood control or transportation infrastructure. The bones of this particular greenway include two and a half acres of native plant habitats around a newly created stream, all filled and irrigated by cleaned stormwater or dry weather runoff. In place of the scrawny wall between the community and Interstate-10, they plan a healthy buffer of shrubs and native oak trees. In any other LA neighborhood there’d be a proper sound barrier says Feldman.

It’s an interesting site, a natural low spot surrounded by hills, capable of capturing runoff from about 650 acres. “We’re redirecting the urban drainage system to increase the sponge capacity of our cities,” says Feldman.

In the case of Ramona Gardens, the tool estimates the proposed project would develop 80 acre-feet of new water supply every year, replacing potable water used to water lawns and ballfields while also irrigating new habitat. The project will also sequester 2,300 tons of Co2 within the plants and trees in 20 years; reduce greenhouse gases by 2,900 tons in the same period; and cost $5-$10 million.

“This is an opportunity to change our environment, and it’s not just about aesthetics, but also about creating places where people can congregate in positive ways rather than in the negative ways we’re known for,” says Calanche, referring to the neighborhood’s reputation for gang violence and police tension.

Though Calanche says the community has been focused on environmental justice, she thinks the new project can expand their conversations to include water. “Maybe it’s time to change policies so we can have front-yard vegetable gardens instead of green grass, which the housing authority is still watering. There are no brown lawns here, but it is a food desert,” says Calanche.


Ramona Gardens homes and front lawns. Photo: Tira Okamoto

Calanche’s voice gets dreamy when she talks about the beauty she imagines the new park will bring to their neighborhood, and how the community’s youth can play a role in making it happen: “We’re excited to really partner, not just be a token partner.”

The Green Solutions team and their funders, which include the Santa Monica Mountains Conservancy and the California Coastal Conservancy, made an active choice to work on Ramona Gardens, according to Vargas. “Other projects in other places might be easier to implement, but true sustainability has to include people,” he says.

Vargas is no tree hugger, but he’s seen the results of making this kind of choice to work in a tough neighborhood first hand. He was the lead engineer for the South Los Angeles Wetland Park, now maintained by the City of Los Angeles Bureau of Sanitation. This award-winning project transformed a 1930s-2008 maintenance yard for buses and rail cars (a former toxic brownfield) into a lush wetland park in the midst of the infamous “South Central” area. The project pulls about 14,000 gallons of dry-weather runoff (40,000 in wet weather) per day out of an adjacent storm drain and passes it through three constructed wetland treatment cells. It then returns any excess, much cleaner, to the drain before it flows out to the Pacific.

The community was shocked when they saw the plans for the project for the first time. “When we said ‘stormwater treatment’ they imagined an ugly black building with smokestacks smelling of sewage,” says Vargas. Instead the community ended up with a parkland of pools, boulders, bridges, flowers, and cattails and bulrushes now so tall they have to be regularly trimmed. “Every morning when we open the gate at 7 am, people flood in,” says Vargas.

South Los Angeles Wetland Park, post construction and later in May 2017. Photos: CCC (overview) and Tira Okamoto (greenery)

Clearly, creating these kinds of natural oases in metropolitan hardscapes can have a ripple affect on the local health and welfare of surrounding communities. The day I visited this nine-acre patch was filled with red-winged blackbirds singing at the top of their tiny avian lungs. Walkers and joggers of every shape and skin tone passed us, making the circuit of the park on crushed granite pathways. Our guide in an orange vest was Majid Sadeghi, Vargas’ public agency counterpart on the project. Sadeghi described how the system first passes its urban water harvest through a giant filter that captures trash by centrifugal force, which is later whisked away by a visiting vacuum truck. From there, the system has two small water pumps for the dry season, three big pumps for the wet season, and ponds capable of holding both small and large volumes. “We capture all the water from surrounding rooftops and streets, and pass it through this park. Using this natural instead of chemical treatment process is cheaper in the long run,” he says. With all the feathery, fragrant greenery, you’d never guess at the elaborate infrastructure hidden within.

“In a high desert Mediterranean climate like Los Angeles, you get rain for 4-5 months then nothing,” says Sean Vargas. “So our technical challenge was how to find the water to keep our urban wetland alive year round. We developed a water budget that used urban slobber when it wasn’t raining, and also had the capacity to treat that first flush of the dirtiest water when the wet season starts.” The first flush washed off city surfaces after a long dry spell is the one with the most accumulated petroleum products, heavy metals, and brake pad dust. Nobody wants that going into the ocean, especially water quality watchdogs.

The Water Management Disconnect

The regulatory hammer on storm water pollution prevention has been over the heads of California cities and counties since the most recent update of the Clean Water Act. Since then municipalities have been experimenting with everything from porous pavers to low impact development (aka LID) to trash capture in a push to prevent pollution from city streets and hardscapes to rivers, bays and the ocean. In 2014, fueled by the Green Solutions’ vision of multi-benefit stormwater projects, California took it to another level. Senate Bill 985, championed by Senator Fran Pavley, offers a framework and incentives for regional land and water managers to do more complex and connected projects.

“Right now we have a very disjointed water management system, both in LA and in other major cities,” says Feldman. The upper LA River watershed where she’s working, for example, includes 11 cities, 14 water districts, various public works departments, a county, a state conservancy, a conservation authority and a “water master,” all with something to say about water. “There’s still a disconnect between the water delivery world, the stormwater world, the water quality and restoration world, and the climate change world.”

Even when there is a connection, Feldman thinks the way most multi-benefit projects are chosen is still too “opportunistic.” Someone has a development they need to mitigate or a property they want to unload or funds they can only get access to if they do one project versus another. “There’s no particular logic,” she says, referring to some of the impetus behind the development of the Green Solutions tool. “We wanted to come up with a prioritized way to do the best projects and get the most water. We’re also trying to de-silo the funding.”

Feldman is wiry and intense. In the last 20 years, she’s generated more than $3 billion in new public funds for parks, river and infrastructure projects up and down California. Vargas calls her a “firebrand out there trying to make great things happen.” She calls him a “visionary hydrologic engineer.” Others in their group seem to share a passion for working with cities and agencies who actually have to get things built on the ground, not just telling them what they should do but can’t or haven’t yet.

State and local land managers are all for making this push. “We’re learning to design infrastructure that works with, rather than against, natural processes, and we need rapid adoption of these alternative designs,,” says Joan Cardellino, south coast regional manager for the State Coastal Conservancy. The Conservancy was an early and eager supporter of the efforts like the Green Solutions tool, which they see as addressing a critical gap. “The hard part is getting the funding and information to the cities that are planning infrastructure upgrades.”

Greening the Grey River

The day that I visited, Feldman got behind the wheel of my car and drove us all over Los Angeles to see the projects mentioned above, as well as several others. But the one she’s clearly most excited about right now is the LA River Greenway Trail. She was on and off the phone most of the day fielding construction questions (the project opened to the public June 3). When we finally arrived at the edge of the river in Studio City, she got out of the car, moved an orange cone so we could park, and strode quickly down to the hardhats to check in.

Any project near the LA River is a priority for the Green Solutions team, but there’s nothing natural about the river, it’s more concrete than earth. The only place the river meanders is between two concrete walls. Most of the year the only water in the LA River derives from a storm, dry season runoff, or the treatment plant upstream.

Gate to LA River Greenway. Photo: Ariel Okamoto

We slip past a striking metal gate, a welded work of river art, and down a path the Green Solutions team has created along the river. This half-mile project connects two other popular riverside trail projects to create four miles of continuous bike and walking path. For years it was the “missing link,” says Feldman, because it was such a challenging stretch of riverbank to drain and plant. On the opposite bank, all we can see is rocky armor. But this bank is green. Here the team is capturing urban runoff in new underground infrastructure and a bioswale, percolating the runoff through soils and roots before it enters the LA River. They have also planted the steep earthy incline with more than 3,000 native trees, shrubs, and flowers.

Newly planted bank and bioswale along LA River Greenway near Studio City, opened to the public in June 2017. Photo: CCC

The team doesn’t use just any plants, they use a very specific mix, density, and spacing of native species modeled on local habitats long since paved over. By organizing them into something they call “habitat tiles,” this planting design offers a scalable unit of upland and riparian species. The unit can be applied to any parcel and then quantified, in terms of the amount of greenhouse gas each tile’s 105-251 trees, shrubs, grasses, and perennials can trap and store. Plants and trees absorb CO2 and release oxygen through photosynthesis, and sequester carbon in their leaves, trunks, stems and roots.

To get these numbers, the Green Solutions team began by computing the impact of a single tree, and then layered it into the appropriate species mix and spacing across 5,000 square feet. “The habitat tile is a useful communication tool to help people understand how we’re breaking down this problem of quantifying greenhouse gas benefit into a replicable unit,” says Tim Kidman of WSP.

Kidman and co-consultants from ESA Associates were responsible for developing all the metrics necessary to calculate the carbon footprint of each potential Green Solutions project. Calculations looked not only at sequestration in plants, but also water delivery distance and onsite energy use for irrigation. Kidman points out that each parcel is unique in terms of water moving costs, as each of the 14 water districts in the upper LA River watershed has its own unique “supplier specific energy intensity factor.”

“At the end of the day, it’s the weighting of all the metrics, and the chance to create an intersection of this information for decision-making, that’s innovative about our tool,” says Kidman. The hope is the strong metrics will help these kinds of ultra urban forestry projects become candidates for cap and trade credits in the climate change mitigation market.

The day we walk the new greenway, the most striking elements are the orange poppies and blue-hearted jimsonweed flowers climbing the banks, and the metal artwork adorning the fence between the walkway and the river. We are one block from busy Ventura Boulevard but I don’t hear a single horn.

Undaunted by Scaling Up

Our last stop offers a contrast to the narrow edges Feldman’s working with in Boyle Heights and Studio City, and shows her ambition. It’s a classic old city park with lots of grass and random trees sprawling over 56 acres. At one end, there’s ballfields, a duck pond, and clusters of concrete picnic tables that must be too hot to sit at in mid-summer. What’s exciting is the size of the undeveloped margin on either side of the LA River channel, lots of space for green solutions like bioswales, treatment wetlands, riparian islands, and river terraces in the suburban sprawl of the San Fernando Valley. “It’s a highly visible and symbolic site to showcase our ideas,” says Feldman.

LA River at Reseda Park in the San Fernando Valley. Photo: Tira Okamoto

One reason Reseda Park is a high priority project identified by the tool is there is enough room to widen the concrete lined banks of the LA River here by up to 350 feet. The project would pump stormwater and dry season runoff from the LA River over an enhanced new flood plain and wetlands, sustain native plants, and recharge groundwater (via a an 8-foot deep, 3.4-acre instillation gallery underground). The site also stands next to a science magnet high school that could learn from an educational circuit through the park.

“I predict that in 10 years, doing a project of this size and scale will be normal,” says Feldman. The idea is to multiply this approach for every watershed in the county.

The way Vargas sees it, “The old way of doing things, with developers bulldozing sites and ramrodding subdivisions through permitting, just can’t happen any more. Not in California’s urban spaces. People are smarter than that. We can’t look at environmental or economic sustainability in a vacuum anymore, it’s not a fad. Our attitudes are really changing, as we see the cost of water rise, as we see the amount of money available to public works departments to do projects diminish, as we see activism and environmental sensitivity grow. All these things intersect, and that’s the happy place we need to do our work.”


Esther Feldman; Sean Vargas; Lou Calanche; Tim Kidman

Related Links

Green Solutions Tool


About the author

Ariel Rubissow Okamoto is both today’s editor-in-chief and the founding editor of ESTUARY magazine (1992-2001). She enjoys writing in-depth, silo-crossing stories about water, restoration, and science. She’s a co-author of a Natural History of San Francisco Bay (UC Press 2011), frequent contributor of climate change stories to Bay Nature magazine, and occasional essayist for publications like the San Francisco Chronicle (see her Portfolio here). In other lives, she has been a vintner, soccer mom, and waitress. She lives in San Francisco close to the Bay with her architect husband Paul Okamoto.

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