S.F. supervisor pushes to untangle freeway Hairball

Photo: Santiago Mejia, The Chronicle The area of Highway 101 near Cesar Chavez Street and Potrero...

Residents of San Francisco’s Mission and Dogpatch neighborhoods have a name for the tangle of freeway arteries that interlock over Cesar Chavez Street, Potrero Avenue and Bayshore Boulevard. They call it the Hairball.

That not-exactly-affectionate moniker encapsulates the frustrations of the bicyclists and pedestrians who travel daily across the numerous ramps and walkways connecting the three streets with U.S. Highway 101. It also sums up the gripes of city officials who have come to think of the interchange as one monstrous relic of the last century, a relic that along with several others in the city could be improved.

“It’s a mess,” said Supervisor Hillary Ronen, who points out that Highway 101 and Interstate 280 form a spaghetti-like labyrinth around the Portola neighborhood she represents, cutting it off from the rest of the city.

“That’s why so few people know about the Portola — it’s literally an island surrounded by freeway,” she said.

Ronen is pushing an idea that some of her colleagues dismiss as illusory, but that she says will make the whole area safer and more attractive: put a chunk of the freeway underground.

“That’s my first choice,” Ronen said as she led a tour of the Hairball’s slithering ramps on a balmy morning last month. She was accompanied by Public Works Director Mohammed Nuru, homeless czar Jeff Kositsky, County Transportation Authority chief Tilly Chang, and Supervisor Malia Cohen, whose Bayview district touches the east side of 101.

From left: Department of Homelessness and Supportive Housing director Jeff Kositsky, District 9 Supervisor Hillary Ronen and Department of Homelessness spokesperson Randy Quezada inspect the area near Cesar Chavez Street and Potrero Avenue on Wednesday, July 26, 2017, in San Francisco, Calif. less From left: Department of Homelessness and Supportive Housing director Jeff Kositsky, District 9 Supervisor Hillary Ronen and Department of Homelessness spokesperson Randy Quezada inspect the area near Cesar ... more Photo: Santiago Mejia, The Chronicle Buy photo Photo: Santiago Mejia, The Chronicle Image 1 of / 13 Caption Close S.F. supervisor pushes to untangle freeway Hairball 1 / 13 Back to Gallery

Also joining Ronen’s tour that day were members of the San Francisco Bicycle Coalition, who are angry about a homeless camp that’s spread along the Hairball’s undulating edges, spilling into bike lanes. Some bicyclists have posted videos of themselves weaving around tents and shopping carts — those videos stoked the political debate and put pressure on city officials to act.

“Elevated freeways are a design that’s no longer chic,” said coalition spokesman Chris Cassidy, noting that he would gladly support a long-term plan to bury the freeway. In the short term, he and other coalition members want San Francisco’s Department of Homelessness and Supportive Services to clear out the Hairball.

To Ronen, the freeway encampment is a natural result of poor urban design. She’s pressuring Kositsky to open a Navigation Center in the area as a temporary solution, while contemplating long-term plans to reconfigure the whole structure.

That could take decades and cost billions of dollars, Chang said. And it would require multiple city and county agencies to collaborate with Caltrans, which owns the freeway. To date, Caltrans hasn’t been officially notified of Ronen’s big plans.

“This would be very expensive, but it would also be a complete transformation,” said Chang, who said she generally supports plans to overhaul freeways.

But there are still a lot of unknowns, like how a dip underground would impact the rest of the system — Highway 101 threads along Bayshore Boulevard, eventually becoming the Central Freeway, which ends at Market and Octavia streets. And it’s not clear where San Francisco would get the money for such a massive, disruptive project.

Ronen also might have a hard time getting approval from her board colleagues, including those whose districts are chopped up by the freeways.

“Well, let’s talk — I haven’t seen a proposal,” Cohen said warily.

During budget negotiations in July, Ronen persuaded her colleagues to set aside $220,000 to start what could be a 25-year freeway redesign process. Half of it would pay for the San Francisco Planning Department to create a new blueprint for the area. The other half would pay for a transportation expert to come up with alternatives for the Hairball and another snarly interchange nearby known as the Alemany Maze.

The maze — a giant, tentacled structure where U.S. 101 and I-280 converge — would be much harder to tackle. Ronen dreams of placing a new layer of land over the maze, quilting it with housing or greenery.

And the bury-the-freeway bug is catching: Supervisor Ahsha Safai, who represents the Excelsior, has also cottoned to the idea of building on top of I-280. Earlier this year he asked the Transportation Authority to analyze the costs and challenges of covering a multi-mile swath that stretches from the Alemany Farmers’ Market to the Daly City border.

“When that freeway was built, it cut streets in half,” Safai said, noting that the additional tier of land would provide vital acreage for a city that desperately needs housing.

San Francisco completed two major freeway redesigns after the 1989 Loma Prieta earthquake, knocking down the badly damaged double-deck Embarcadero Freeway and later demolishing the overhead U.S. 101 ramp along Octavia Boulevard.

Those two projects helped inject life into neighborhoods that had previously been desolate, said Jason Henderson, a professor of geography and environment at San Francisco State University who specializes in urban transportation.

“That Embarcadero (waterfront) used to be a place where no one wanted to go, and now it’s beautiful,” Henderson said.

Similarly, he said, the freeway demolition on Octavia helped reconnect the Lower Haight and Hayes Valley neighborhoods with the Civic Center, and transformed Hayes Valley into a chichi pocket of boutique shops, taprooms and expensive homes.

In both cases, Henderson said, the city opened up new land that it could sell to underwrite the new infrastructure.

The concept of razing or concealing invasive freeways has caught on in many parts of the country, and transportation wonks in San Francisco have their eyes set on several aging stretches of asphalt. The one that’s most ripe for a redo, according to Henderson, is a crisscross where I-80 and U.S. 101 split in multiple directions over Division Street. Public Works officials periodically sweep out homeless people who camp beneath those overpasses.

The city could revitalize that area by cutting out part of 101 and extending Octavia Boulevard to Bryant Street, which would also create space to run a Muni line into Mission Bay — a neighborhood that still lacks transit connections, even though it’s seen plenty of new development.

Ronen, who lives in the Portola and whose husband regularly bikes across the Hairball on his way to work in the public defender’s office, has refused to let cost projections get in the way of her vision.

“I don’t want us to be limited by finances,” she said. “I want to think big.”

Rachel Swan is a San Francisco Chronicle staff writer. Email: rswan@sfchronicle.com

Twitter: @rachelswan