About ten years ago, six lanes of traffic sped along the stretch of Guerrero Street south of Cesar Chavez Street at 50 miles an hour. Pedestrians needing to cross the street sometimes waited 10 minutes to work up the nerve to make a break for it.

But the scene was tranquil on Saturday, in the new Guerrero Park where about 30 neighbors mingled around a grill, marveled at a fruit tree at peak bloom and watched their children play — all on a wedge of pavement that’s been wrested from the cars for the people.

Created in September, the park is the latest in a series of efforts to make the San Jose/Guerrero neighborhood, also called  La Lengua,  that straddles Noe Valley, Bernal Heights and the Mission District, more livable. It’s also part of a city-wide push to turn pavement into temporary, low-overhead community spaces.

Gillian Gillett was a driving force behind the park's creation.

“Before, this was just a parking lot. It’s great to see how a space can change,” said Brooke Dubose, a transportation planner who lives across the street from the park. Residents used to leave their cars in what is now a mini-plaza blocked from the street by logs and planters of flowers and bamboo.

Manning the grill was Andres Power, the manager of the Pavement to Parks Program — the City project that helped the neighborhood put the plaza in place. He explained that, while the city has many larger parks, it lacks the smaller, plaza-like spaces where people gather in European cities.

So, his office is working with community leaders to create small, temporary parks across the city. The Mayor wants a dozen such parks in place by the end of summer, Power said. So far, there are four. A parklet at 22nd and Bartlett Streets, to be designed by Rebar Collective, is in the works. Another is proposed for 24th and Noe Streets, but it’s caused controversy — some residents at a packed meeting last week expressed concern that the parklet would disrupt traffic.

Neighbors came out despite the gray day.

The parks go up relatively quickly and are made with temporary materials so they can be easily be tweaked or dismantled if they aren’t working. “This is planning in action,” said Power.

The parks can also become permanent fixtures — that happened just last Thursday when the city began replacing the temporary elements of the Castro Commons at 17th and Castro with permanent ones. The park is there to stay.

Many at the Guerrero Park barbecue think their park is a keeper, too. Among them is Gillian Gillett, who as co-chair of the San Jose/Guerrero Coalition to Save Our Streets was a driving force behind the park’s creation. “We have created an urban environment that’s really unfriendly to life,” she said. To counter that, she and other neighbors have gotten the city to narrow Guerrero Street to four lanes, lower the speed limit from 40 to 25 and green the  median strip.

Andres Power manages the City's Pavement to Parks program.

Andres Power manages the Pavement to Parks program.

These efforts, she hopes, will keep families in the moderate to middle-income neighborhood. “I used to worry that my kids weren’t going to learn to ride a bike,” she said, before pointing out the absurdity of packing her kids in the car and driving them to another neighborhood to learn to ride.

Overall, the neighborhood has been supportive of the park, Power and Gillett said. Still, some longtime residents of the neighborhood are upset that they’ve lost their favorite — though possibly unauthorized — parking space. And a basketball hoop was removed from the park after neighbors complained that young men used it at night and made noise.

Guerrero Park  was designed by Jane Martin, a landscape architect based in the Mission. It cost just over $20,000 to build. None of the funds came from the city, Power explained, but from businesses including St. Luke’s Hospital, Mitchell’s Ice Cream and Safeway. Neighborhood residents maintain the park.

Michael Pryfogle, who lives a block away, said residents of other neighborhoods considering similar mini-parks shouldn’t dismiss the idea. He feels safe enough to let his 9 and 11 year old kids go to the park alone, and it’s a favorite spot for his children to skateboard and bike.

“You don’t need a huge space. You don’t need green grass. I just want enough space so I can play catch with my kids,” he said.

Suzanne Riessen, a Tiburon resident who’s son lives near the park has watched as the space has materialized. “This is a good example of what you can do with the most awful piece of concrete,” she said.