... Don't panic. It's a routine venting of natural gas from a pipeline in Spokane Valley.
Gas Transmission Northwest LLC, a partly owned subsidiary of TransCanada Corp., said in a news release that the company will vent a 36-in. diameter pipeline in preparation for upgrades to the line. The process, called a "blow-down," is considered routine and doesn't pose a threat, but it's very, very loud, the company said.
"Even if you know it's coming, it can be disconcerting. It can sound like a jet airplane circling the house at low altitude for about 45 minutes," a company spokesman said.
The company has notified about 2,400 households near the site, at 32nd Avenue just east of Barker Road, the release said. The blow-down begins at 10 a.m. Monday. Access to the area will be restricted and some roads will be closed for the duration of the venting. For information, contact Steve McNulty at (509) 533-2833.