New ‘green stormwater spine’ in West Berkeley aims to clean water traveling to the bay

Computerized image of dry plants and a purple tree in a cut-out along a sidewalk
Special plants and soils are being installed along San Pablo Avenue at Harrison Street to clean stormwater before it goes into the creek. Rendering: Courtesy San Francisco Estuary Partnership

On the last block of San Pablo Avenue before Berkeley gives way to Albany, natural and commercial worlds collide.

The calm Codornices Creek runs alongside a drive-through McDonalds and perpendicular to a major cross-city thoroughfare. When it rains, stormwater mixes with the particulate matter from the cars driving down the busy street and pours into the creek, which carries the tainted water to the bay.

A new “green infrastructure” project under construction along the western side of the block is designed to slow down that process by detoxing the water through soil and plants and pumping a purified product back out to the creek. The project, a whopping seven years in the making, is part of a $4 million, four-city effort funded by the Metropolitan Transportation Commission (MTC), Caltrans and another state grant.

The Berkeley segment of the so-called “green stormwater spine” is the first to be built, and work, which started Monday, is expected to be completed by Thanksgiving.


The finished product will make dirty rainwater “wash into the landscaped areas, pool, and soak into special soils. Plant communities will draw up the pollutants,” said Josh Bradt, project manager. Bradt works for the San Francisco Estuary Partnership, a program of the Environmental Protection Agency that’s housed at the Association of Bay Area Governments and staffed by MTC.

Standing at the construction site — which is currently dominated by bright orange k-rails and cones —  one needn’t look far to find a version of what’s going to be built there. The neighboring McDonalds already has lush bioswales and curved drainage systems installed its parking lot.

“This work is done in the private sector all the time because it’s often a condition of development,” said Bradt, walking through the restaurant’s lot Monday, the day the spine broke ground. “This is kind of a catalyst project for cities to see how it works.”

Construction workers dig along k-rails
Crews started work Monday on a green infrastructure project along San Pablo Avenue at the Berkeley/Albany border. Photo: Natalie Orenstein

Berkeley has done some similar “bioretention” work at a few sites throughout the city.

The “showcase” project is the bioswale at Presentation Park on Allston Way and California Street, said Danny Akagi, an associate civil engineer with the city of Berkeley. Another was built recently at Hearst Avenue and Oxford Street as part of the “complete streets” project there. There is another new green infrastructure feature where Hopkins and Rose streets intersect.

It’s not always easy to find an appropriate location for a rain garden or bioswale in Berkeley.

“Each site has its own constraints,” Akagi said. “We want to try to get these in and not create excessive impacts to other users. It’s a tradeoff — do we have parking or do we have something to treat the water?”

Green infrastructure also comes at a price, whether it’s the cost of dealing with underground piping or the competitive construction market. However, in 2018 Berkeley voters decided to increase the city’s clean stormwater fee for the first time since it was introduced in 1991. The fee rose by around $43 annually for the average owner of a single-family home. The revenue will be spent on piping and green infrastructure projects.

“Financially we’re in a better position than we were two years ago,” Akagi said.

Project manager Josh Bradt gestures toward a bioretention system in a McDonald’s parking lot. Photo: Natalie Orenstein

The city is preparing to submit a mandatory green infrastructure plan to the regional water board by Monday. Earlier this month the City Council approved the plan, which identifies 11 priority sites for projects. Most are in West Berkeley and multiple fall along Codornices Creek. According to the city, it would cost $1.7 million to build all 11 projects and another $100,000 a year to maintain them. The plan also sets a goal of treating another 17 acres of runoff in the next 10 years ($8.9 million).

The “green spine” project planners intentionally selected sites along bustling right-of-ways, to show that this work could be possible anywhere, Bradt said.

And he thinks the added greenery will “beautify” an urban block.

During construction, one of two southbound lanes on the San Pablo Avenue stretch will be shut down from 9 a.m. to 3 p.m. The finished product will replace four existing parking spaces.

The ultimately two-month construction project has taken the better part of a decade to come to fruition. Bradt was actually working for the city of Berkeley as a watershed specialist in 2012 when the Estuary Partnership approached the Public Works Department about a seven-city bioretention effort. Cities could pitch their own sites.

There was a sparsely attended Public Works Commission meeting on the topic in Berkeley, said Bradt, who went door-to-door at the time alerting neighbors to the proposal. (He later took a job with the San Francisco Estuary Partnership.)

When contractors finally got to potholing in 2016, they came upon much more underground infrastructure than anyone realized was there.

“That stopped the whole project in its tracks,” Bradt said.

Planners went back to the drawing board and whittled the list down to four cities: Berkeley, Oakland, Emeryville and El Cerrito. The work includes $700,000 in water pipeline moving and upgrading, Bradt said. Marin-based contractor Ghilloti Brothers is lined up to do all of the sites.

Once the work is done, the city will be responsible for maintaining the site, tending to the plants, clearing trash, and making sure it’s draining properly.

Codornices Creek runs perpendicular to San Pablo Avenue in West Berkeley. Photo: Natalie Orenstein

Seven years since the project was proposed, Bradt returned to neighboring businesses and residents to let them know construction was starting.

Back when they were first alerted, “most folks were very open and receptive to it,” according to Bradt.

This time, one shop owner across the street was skeptical.

“To me, it’s just a waste of money,” Sam, of Gilman Auto, told Berkeleyside. He didn’t want to give his last name.

“If what they’re doing is going to work for the environment, I’m all for it. But I don’t trust the system,” Sam said. “Parking is challenging anywhere in Berkeley,” let alone when four spaces are eliminated.

Advocates of the project said this sort of infrastructure has been shown to filter the heavy metals, oils and automobile wear-and-tear that gets mixed into stormwater before it’s fed to the fish in the creek.

“There have been studies on how these behave and on their ability to remove contaminants from urban runoff,” Akagi said.

But will a handful of small, scattered bioswales have a large-scale impact on water quality and environmental health?

“It’s a good question,” Akagi said.

The steelhead trout swimming right past San Pablo will certainly be happier.

“But the rest of the watershed going into Codornices Creek extends two miles to the east and up into hills, and we don’t have a lot [of infrastructure] up there yet,” Akagi said. “It’ll take time.”