Crews are working to repair a water main break in San Francisco this afternoon, fire and SFPUC officials said.

According to SF Fire Department spokesperson Mindy Talmadge, fire crews responded to a report of a buckling sidewalk on Joost Avenue near Congo Street at 12:26 PM.

Instead, they discovered an 8-inch water main from 1929 that had burst due to age, San Francisco Public Utilities Commission spokeswoman Alison Kastama said.

While the break did flood the roadway, Kastama said that water didn't reach the interior of any area buildings.

Kastama says that crews are working on excavating the line for repairs, which typically take between four and six hours. Until the repairs are made, residents at the 300 block of Joost are without water, and the block is closed to traffic.