A two-block radius near a busy Union Square intersection was closed most of Wednesday afternoon after a 10-inch gas main broke in the middle of the street in San Francisco.
The gas main was puncture by third-party construction crews at the intersection of Post and Mason streets at 2:15 p.m., according to PG&E spokesman Joe Molica.
Although PG&E crews shut off the gas by 3:20 p.m., the streets surrounding the break were closed for most of the afternoon. Mason Street between Sutter and Geary streets, along with Post Street between Taylor and Powell streets, remain closed.
As a precaution because of the San Bruno blast roughly one year ago -- which killed eight people and destroyed 38 homes in the Crestmoor neighborhood -- two buildings on Post were evacuated, including an Academy of Art building and the San Francisco Flex Academy high school.
Molica said the 10-inch main is the pipe that delivers gas to homes and businesses. There is no estimated time for service in the area to be restored.
An ou-of-town visitor in San Francisco on business said he was walking by the construction crew when the break occurred.
The man, who declined to give his name, said he thought nothing of the break as he walked by because he saw construction was going on in the area.
“It sounded like an air compressor,” he said.
The same sound was heard from roughly one block away as crews worked to turn off the gas. Molica said before repairing the break, PG&E crews would work to release all the gas left in the pipe.
The Powell-Mason cable car line was stopped for 20 minutes. However, service on the 2-Clement and 3-Jackson was affected for riders heading toward downtown San Francisco.