PORT ANGELES — Traffic delays at the Elwha River bridge on U.S. Highway 101 will resume Monday.
Closure times are estimated to be from about 1 p.m. to 3 p.m. Monday and from 4 p.m. to 6 p.m. Tuesday, the state Department of Transportation said Friday.
Exact times of the closures will depend on work progress as crews move equipment between the bridge deck and the river for continued drilling operations near the two bridge piers in the riverbed.
Transportation officials advised drivers to consider detouring via state highways 112 and 113.
Drilling was interrupted last week when the focus of work changed to placing large boulders around the base of the bridge’s piers to curtail erosion in the advent of high water during an expected storm. The storm blew into the North Olympic Peninsula on Thursday night and will continue to drop rainfall on the region this weekend.
Drilling is part of the process of evaluating the condition of the piers following erosion observed since the removal of the Elwha Dam in 2012, according to Chris Keegan, regional operations engineer for the state Department of Transportation.
Sediment and high water washing down from the former Lake Aldwell, which had formed behind the Elwha Dam, has eroded some 14 feet of the riverbed at the area of the piers that support the bridge, Keegan said.
The bridge is safe, Keegan said, adding that bridges are inspected on a regular basis; however, the erosion is a concern to engineers, he said.
During the closures, transportation crews will lower equipment from the bridge deck to the riverbed and spend the week drilling bore samples along the bridge piers to determine the current level of bedrock.
The samples will provide information on the type and depth of material under the bridge foundations, Claudia Bingham Baker, Transportation spokeswoman, has said.
The Elwha Dam and another dam upstream, the Glines Canyon Dam, were removed as part of a $325 million National Park Service project to restore the Elwha River to its natural state.
Updated information will be posted on the What’s Happening in the Olympic Region web page at http://tinyurl.com/PDN-dot olympicregion, Transportation officials said.
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Features Editor Chris McDaniel can be reached at 360-452-2345, ext. 56650, or at cmcdaniel@ peninsuladailynews.com.