Culvert failure forces road's closure
A culvert failure caused a slope on the south side of West Pine Street to give way on Thursday. The exposed pipe in the photo is a water line for landscape irrigation, not the gas and potable water lines also embedded in the roadway. (Photo by KEITH KINNAIRD)
SANDPOINT — Pine Street west of Travers Park was closed on Friday after a culvert failed and caused part of an embankment to erode into Chuck Slough.
Bonner County and city officials hope to reopen the stretch of road today.
The problem was discovered late Thursday afternoon and crews spent Friday working to stabilize the slope and making preparations to replace the stricken section of culvert.
“Hopefully we can get it wrapped up tomorrow,” Bonner County Road & Bridge Director Ryan Luttmann said on Friday.
Luttmann said a void developed around the southern end of the culvert, likely because of the recent dousing of wet weather and high runoff.
“Once the void was large enough, that pipe dropped,” Luttmann said, referring to a 30-foot-long, 6-foot-wide segment of culvert.
Soils around the culvert became supersaturated at the foot of the slope and sloughed away, causing uphill soils to also give way.
Sheet piling and cribbing was installed to stabilize the slope, said Luttmann, who anticipates a new section of culvert will be installed today.
The compromise was of particular concern because there are subterranean transmission lines in the road embankment. There is an 18-inch, high-pressure city water line and a 4-inch, low-pressure Avista gas line, but Luttmann said both facilities have escaped harm.
Bonner County commissioners declared a state of emergency on Friday so Road & Bridge could immediately hire contractors without having to go through lengthy procurement procedures, commission Chairman Joe Young said.
The declaration also enables the county to seek reimbursement through the Idaho Bureau of Homeland Security if costs spiral out of control.
The county has hired Interstate Concrete & Asphalt and CE Kramer Crane & Contracting to assist with the repair project.