City says it will take 6 weeks to repair massive sinkhole in SF

A massive sinkhole that formed after a water main broke in San Francisco’s Cow Hollow neighborhood Monday likely won’t be repaired for six weeks or more, city officials said Friday. 

Fillmore Street between Green and Union streets will remain closed to all traffic and street parking while crews repair the roadway, Joseph Sweiss, a spokesperson for the San Francisco Public Utilities Commission wrote in an emailed statement.

The water main broke late Sunday night at the intersection of Green and Fillmore, flooding streets with water and debris. Some ground-level homes and businesses were inundated with water, and Monday morning, the area was a muddy mess. “There’s got to be a foot of mud in the street,” Laurie Thomas, owner of Rose’s Cafe on the corner of Union and Steiner streets, told SFGATE on the phone Monday morning.

Later Monday, a sinkhole appeared in the middle of the intersection where the pipe broke. “The flow of pressurized water dislodged the sand and soil underneath the intersection, causing the pavement to buckle and form a sinkhole,” Sweiss wrote.

While the broken water main has been repaired, the roadway still needs to be reconstructed. Before the road work can even happen, the water, sewer and gas pipelines and sewer laterals on the block of Fillmore between Union and Green streets need to be replaced, the agency said. 

“We are working on a detailed schedule, however, we anticipate the work will take 6 weeks or longer to complete,” Sweiss wrote in the statement.

Some 1,200 miles of pipes carry water running under the city, and SFPUC said 20% of those are around a century old and made of cast iron. A project to replace the old pipes is underway, but until that’s complete, breakages can occur in the old mains. The pipe that burst Sunday was one of those old pipes and more than 70 years old.