A natural gas leak in downtown Vancouver on Thursday morning prompted street closures and the evacuation of several buildings, including a motel.
When the all clear was issued around 12:30 p.m., no one was injured and no fires were reported.
Many downtown streets were temporarily closed between Evergreen Boulevard and Mill Plain Boulevard, including C, Broadway and Main streets. The I-5 southbound off-ramp at Mill Plain was also temporarily closed because of the leak.
A private contractor hit a one-inch low-pressure gas line near 12th and D streets and notified Northwest Natural and 911 around 9:20 a.m., said Jenna Cooper-Gross, Northwest Natural spokeswoman.
The contractor, C2, was installing casing around a pipe in the area when it hit the low-pressure distribution gas line, she said.
About 25, firefighters, including a HazMat unit from Vancouver fire and firefighters from Clark County Fire District 6, responded.
Scott Willis, Vancouver fire spokesman said Northwest Natural crews found potentially explosive levels of gas in the storm and domestic sewers.
Natural gas, which is lighter than air, seeped into the ground surrounding the pipes.
“Sewer lines are porous and packed in gravel, not dirt,” Cooper-Gross said. “Natural gas finds the path of least resistance and went into the line that way.”
Crews also found a small amount of gas in the upper level of the Comfort Inn motel, Cooper-Gross said. Guests in that portion of the motel were relocated to a lower floor temporarily as a precaution, she said.
The sewers and the motel were ventilated with a vapor extractor, a device that draws a high volume of air out of a hole. Firefighters and Northwest Natural employees continued to monitor gas levels in the sewers surrounding the motel.
Crews also used machinery to dig holes to check underground gas lines.
The site is only a couple of blocks from the former Vancouver city hall, where an emergency mass-casualty drill was in progress. However, the gas leak was not part of the drill. The old city hall was pressed into service as a media briefing area.
Crews removed the damaged piece of steel pipe and put in a replacement piece.
In an ironic twist, workers at the new Vancouver City Hall, 415 W. Sixth St., were practicing an evacuation drill at the same time the gas leak was forcing real evacuations.
Firefighters say the incident should serve as a reminder.
“You always call before you dig,” spokesman Willis said. The private utility did call, but even so struck a line and prompted the emergency response, he said.
Anyone who plans to dig should call 811 two business days before digging to arrange for technicians to come to the scene and mark underground lines, cables and pipes.
Reporters Eric Florip and Marissa Harshman contributed to this story.