Broken natural gas line repaired; Colorado Ave. reopened

An excavation subcontractor struck and ruptured a 4-inch pressurized natural gas line at the Colorado Ave Dam safe passage project in Bend Tuesday morning, prompting closure of the area, including the bridge and road, for over two hours, officials said.

Deschutes County 911 dispatchers got their first call at 7:46 a.m. about the leak, and police soon closed the Colorado Avenue bridge over the Deschutes River and detoured drivers onto other routes for their morning commute. Police and fire crews were on scene.

Around 9 a.m., the city of Bend tweeted, “It’s going to be a couple of hours before crews can find and shut off” the leak, and noted that winds were carrying the gas toward the northeast.

Shortly after 10 a.m., Bend Fire Battalion Chief Dave Howe said the leak had been sealed and Colorado Avenue reopened before 11 a.m., after officials assured gas levels through the area were safe. A utility spokesman said the leaking natural gas was shut off at 10:11 a.m.

Howe said fire crews protected the utility workers with a charged hose line as they worked to install a valve and close the leak. There was a light, variable breeze, mostly to the southwest.

The emergency phone notification system was used to advise nearby residents and businesses that no evacuations were necessary but that people should avoid the area, Howe said.

A park district spokeswoman said Hamilton Construction is the general contractor on the project.

Evan Stuart, project manager for Hamilton subcontractor JAL Construction, said they originally believed it was a six-inch main gas line, as they had been removing the supposedly abandoned four-inch line in their work on the project at McKay Park.

“There was a four-inch line running across the old bridge,” Stuart said. “To tear the bridge out, the line had to come off. We’d been in contact with CNG about removing it. Our understanding was that it had been terminated at the road right of way. There was a misunderstanding, and they didn’t know they were 150 short of the right of way.”

“We knew where the line was” that was being removed, he said. “All of a sudden, it was live.”

People in the area could smell the “rotten egg” odor added to otherwise odorless and colorless natural gas from some distance away, and onlookers were kept a sizable distance back from the location along the Deschutes River.

Cascade Natural Gas spokesman Mark Hanson said the intermediate pressure line was struck by a third party working in the area. He added that no customers were directly affected.

The risk of explosion is relatively minimal, as “natural gas dissipates pretty quickly when it goes in the air,” Hanson said from Bismarck, N.D., headquarters of CNG’s parent company, MDU Resources Group.

As for repairs, Hanson said crews “if they are lucky have a valve close by. Sometimes they have to pinch it off at both ends and cap it, so no gas is flowing so they can make repairs.”