JUNE 30, 1997
Firefighters escorted families from a gas leak north of Woodinville-Duvall Road Friday afternoon.
Photo by Lisa Allen/Northwest News.
by Andrew Walgamott and Lisa Allen
Workers removing old equipment from a natural gas pipeline near Woodinville-Duvall Road caused a major gas leak Friday afternoon, halting traffic for several hours and forcing the evacuation of dozens of people in the area.
One pipeline worker suffered minor injuries and another was flung 40 feet when crews accidentally pulled a "gate" off of a 26-inch pipeline, releasing 9 million cubic feet of natural gas, according to Northwest Pipeline District Manager Grant Jensen.
According to Jensen, crews working on parallel 26-inch and 30-inch gas pipelines near 214th Avenue NE were disassembling valve connectors that once fed local gas lines. He said a 2-inch valve on the 30-inch pipeline had come out without any trouble. But when a backhoe was used to help lift the 150-200 pound 4-inch valve, workings inside the 26-inch pipe came with it.
Doug Antosen, a laborer who was working in a trench next to the four-foot tall valve, said he was thrown 40 feet from the trench when the gas suddenly shot into the air. He recalled being in the trench one moment and suddenly face down in the muddy pipeline right-of way the next.
The leak sent a plume of gas that could be smelled in helicopters 4,000 feet above the scene, according to news reports. Choppers were warned away from the scene by police.
Officials, worried about an explosion, blocked off Woodinville-Duvall Road at Avondale Road and 227th Avenue NE. Evacuation was initially ordered for homes in a mile-wide radius of the leak. Dozens of families left their homes. Some gathered at the Duvall Fire Station. A shelter was set up temporarily at Bear Creek Elementary.
According to Jensen, the greatest chance of an explosion was near the fringes of the leak. He said that the fuel mixture at the leak was too rich to explode.
The evacuation was short-lived. Crews were able to depressurize the 26" line by 3:30 p.m. by shutting off valves at Snohomish and Redmond. Woodinville-Duvall Road was reopened a short while later and families were allowed to return to their homes.
By Friday night, Northwest Pipeline crews had welded a cap over the hole in the pipe and service was resumed over the weekend. Local gas service was not disrupted.
The pipeline runs from Canada to Colorado through Washington, Oregon, Idaho and Wyoming. Two recent explosions on the same pipeline near Bellingham and Kalama were attributed to sliding rain-soaked soil.
According to Northwest Pipeline Communications Manager Susan Flaim, less than $11,500 worth of natural gas was lost in the leak. "It's important to note that the costs won't be passed on to our customers," Flaim said.
The deafening roar of escaping gas could be heard for 15 blocks.