Gardens in building lobbies improve air quality and soften the interior aesthetic, but the garden that's sprouting inside the new headquarters of the San Francisco Public Utilities Commission (PUC) does something extraordinary. Treated sewage flushed from the floors above courses through the gravel-lined patch, removing methane and other impurities before the water is funneled back up for reuse within the building's bathrooms.
The water-recycling facility is among a long list of green features in the new 13-story building at 525 Golden Gate Avenue, which was crafted to help the city agency practice the same water and energy conservation practices that it preaches. Opened in late June, it’s expected to use less than half the water typically used by a similar office building, pull 33 percent less energy from the grid, and secure a LEED Platinum rating.
Agency officials could learn within a year whether this is the nation’s greenest public building. That’s how long it may take to finalize its LEED score. “The PUC really wanted to make a statement about the city’s commitment to sustainability,” said architect David Hobstetter of KMD Architects, designers of the project.
Hobstetter had been working since 2000 with the city to design a replacement for a boarded-up building at this prominent site near City Hall that was irreparably damaged by the 1989 Loma Prieta earthquake. Following a political spat over whether the city should spend heavily on an uber-green building amid recession-era budget cuts, construction began in 2009 and the 277,500-square-foot building opened in June at a cost of $200 million. Construction cost $528 per square foot.
The new landmark sits at the edge of San Francisco's Civic Center district, incorporating granite features that match the historic buildings to its south. Sloping glass walls help it nestle into the ramshackle residential neighborhood to the north.
“The first challenge for us was trying to work within the historic context of the City Hall area,” Hobstetter said. “All those buildings are classic Beaux Arts buildings, which are not designed with a particularly strong eye toward sustainability.”
Other features include louvers and blinds that adjust automatically, copious use of recycled construction material, rainwater tanks, hundreds of solar panels, and four vertical-axis wind turbines embedded into the building’s north facade.
“That is an example we want to set,” said Ed Harrington, general manager of the San Francisco Public Utilities Commission. “We hope this will generate enthusiasm among other people to say, ‘We can do this. This makes sense to do.’”