A five-alarm fire at a construction site in San Francisco pulled in over 150 firefighters on March 11. The crews battled flames spewing from a 172-unit apartment complex owned by BRE Properties and successfully prevented the fire from jumping to other construction projects in the growing Mission Bay area of the city.
Though, immediately afterward, the site remained too dangerous for investigators to enter the building to start searching for the cause of the fire, early reports of welding on upper floors of the six-story MB360 apartments, also known as Block 5, focused attention on the construction work under way at the 312,000-sq-ft complex.
Crews reported that, in the area of fire origin at Fourth Street and China Basin, there was some work being done on the upper floors, says San Francisco Fire Chief Joanne Hayes-White. "It is still preliminary, but we did hear there was some welding work being done," she states. City officials have confirmed the fire started above ground.
BRE, a San Francisco-based developer, employed the San Francisco office of Boston-based Suffolk Construction to build the approximately $227-million project, which had been scheduled to open later this year. Suffolk did not respond to a request for comment.
Hayes-White says that, near the end of the day's work at the block-long site, some construction personnel were still "picking up" when fire crews arrived close to 5 p.m. Most of the construction workers had left the area by 4 p.m.
San Francisco Mayor Edwin Lee (D) praised fire-department crews and an auxiliary high-pressure water system for keeping the blaze contained to the building of origin, especially in an area surrounded by apartment developments under construction.
"But for the high-pressure water system, this fire would, perhaps, have been very hard to contain," Lee says. "It allowed for the 150 firefighters to have apparatus and a system work in their favor to contain this as fast as they did."
Lee credited strategic city planning in the growing area near AT&T Park—home of the San Francisco Giants baseball team—for the fire containment, including the recent infrastructure improvements that added both a low-pressure and high-pressure water system.
Two firefighters suffered minor injuries, but the fire caused no major injuries or deaths.