The broken 12-inch main was reported around 4:25 a.m. near the intersection of Williams Street and Leonard Drive, EBMUD spokeswoman Andrea Pook said.
The broken pipe caused flooding in the street, which is near John Muir Middle School, Pook said. The school is off for winter break and was not damaged by the flooding, she said.
Utility crews have responded to repair the pipe and clean up debris in the street, according to Pook.
Police also responded to direct traffic around the site, police spokesman Lt. Jeff Tudor said.
Pook said there is no estimate yet for when the pipe will be repaired.