Homes and businesses near the intersection of Danville Boulevard and Stone Valley Road in Alamo were evacuated late Wednesday morning after an East Bay Municipal Utility District construction crew ruptured a 1.5-inch gas line with a backhoe around 10:35 a.m.
The evacuation order was lifted about 3:30 p.m. after PG&E made repairs, although Danville Boulevard in Alamo between Stone Valley Road and Las Trampas Road remained closed as repairs continue. Danville Boulevard north of El Cerro Boulevard was limited to local traffic only.
When told to evacuate, residents were advised to turn off all heat sources in their homes, lock all doors and windows, and take with them only essential items that could be carried. Pets had to be in a carrier or on a leash, emergency officials said.
Danville Boulevard was closed for about half a mile, between Las Trampas Road and St. Alphonsus Court, and the Stone Valley Road exit from Interstate 680 was blocked off, said Kim French, spokeswoman for the San Ramon Valley Fire Protection District.
She said homes and businesses within a roughly 1,000-foot radius of the leak were evacuated.
Alamo Plaza Shopping Center was evacuated along with other nearby businesses, and residents who live on Alamo Square Drive, across the street from the broken gas main, were told to leave their homes immediately and go as far south as possible, according to the Contra Costa County Sheriff's Office.
"All the folks here on scene are working together to formulate a plan," French said this afternoon. "As soon as it is safe to reopen the area and let people back in we will do so," she said.
The East Bay Regional Park District evacuated the Iron Horse Trail; PG&E, the California Highway Patrol and EBMUD also responded.
Traffic built up surrounding the area as vehicles were rerouted from westbound Livorna Road and Stone Valley Road onto I-680, and those approaching central Alamo on Danville Boulevard were turned around. The freeway was congested for several hours as off-ramps into Alamo were closed.
The evacuation order was lifted about 3:30 p.m., and roads reopened in the afternoon after the gas line was capped, authorities said.
PG&E crews were able to stop the leak around 3:30 p.m., utility spokeswoman Tamar Sarkissian said.
It took crews several hours of digging and jack-hammering to be able to make the needed repairs, she added.
The Alamo Chamber of Commerce sent notices to members shortly before 2 p.m. that downtown Alamo had been evacuated due to a gas leak, which was expected to be in effect until 6 p.m., so its ribbon cutting at Stone Valley Dental and a mixer at Ace Hardware were canceled for this evening.