"We are trying to be as creative as possible with the use of materials the city already has on hand," Power said. In addition to the DPW yard that Rebar tapped for Showplace Triangle, Power said the Public Utilities Commission, Port of SF, and the Recreation and Parks Department all have yards around the city that are filled with materials.
"They each have stockpiles of unused stuff that has accumulated over the years," he said.
For her Pavement to Parks project on Guerrero, Martin used fallen trees that originally had been planted in Golden Gate Park — pines, cypress, eucalyptus — but were headed for the mulcher. Not only were they great for creating a sense of place, they offered a nod to the city's natural history.
But perhaps the coolest material that had been sitting around for decades was the massive black granite blocks that Rebar incorporated into Showplace Triangle. "One of the most interesting materials that we used in Showplace Triangle was the big granite blocks from Market Street that were taken off because merchants didn't like people encamping there. They were too successful as spaces, so they got torn out," Merker said.
Bela said they couldn't believe their eyes: "We saw these stacks of five-by-five by one-foot deep black granite. Just extraordinary. If we were to do a public project today, we could never afford that stuff. There's no way. But the taxpayers bought that stuff back in the '70s and now it's just sitting there in the DPW yard. It's a crime that it's not being used, so it was great to get it back out on the street."
Radulovich said the return of the black granite boxes to the streets represents the city coming full circle. He remembers talking to DPW manager Mohammad Nuru as he was removing the last of them from Market Street in the 1970s, citing concerns about people loitering on them.
"To see them put up again in JB's project was symbolic of where the city went and where it's coming back from," Radulovich said. "It's almost like the livability revolution got interrupted and we lost two decades and now it's picking up again."
Back in the 1970s, Radulovich said the city was actively creating new public spaces such as Duboce Triangle. It was also creating seating along Market Street and generally valuing the creation of gathering places. But in the antitax era that followed, public sector maintenance of the spaces lagged and they were discovered by the ever-growing ranks of the homeless that were turned loose from institutions.
"The fear factor took over," Radulovich said. "We did a lot to destroy public spaces in the '80s and '90s."
But by creating temporary public spaces, people are starting to realize what's been lost and to value it again. "These baby steps are helping us relearn what makes a good public space," Radulovich said.
For much of the younger generation, building public squares is a new thing. As Aguilera noted, "We don't have a lot of public plazas anymore or places for people to gather. When Obama was elected, where did everyone go in the city? Into the streets. So we're trying to give that back to the city."
CARS TO GARDENS
Perhaps the most high-profile laboratory for these ideas is the Hayes Valley Farm, a temporary project planned for the 2.5 acres of freeway left behind after the Loma Prieta earthquake. The publicly-owned land between Oak and Fell streets is slated for housing projects that have been stalled by the slow economy.
"The site's been vacant for 10 years. They came up with a beautiful master plan. And the moment they're ready to move on the master plan, there's an economic collapse, so nothing is happening," Bela said.