91视频

Submitting Firm: David Evans and Associates Inc.
Location: Columbia River Gorge
Client/Owner: Oregon Department of Transportation and Western Federal Lands Highway Division
Other Consultants/Key Participants: Conway Construction Company, GRI
Additional Stakeholders: Historical Columbia River Highway Advisory Committee, Multnomah County, Oregon State Parks and Recreation Department, Union Pacific Railroad, U.S. Forest Service

After being abandoned for multiple decades and reconstructed in 2009, the Oneonta Tunnel was damaged by the 2017 Eagle Creek Fire and rendered unusable. ODOT and Western Federal Lands Highway Division partnered to rehabilitate the tunnel, which is part of the Historic Columbia River Highway State Trail.

David Evans and Associates Inc., which worked on the 2009 restoration, and GRI performed a conditions assessment of the tunnel and Oneonta Bluff. After using innovative technologies to safely assess conditions, the team performed preliminary engineering to rehabilitate the tunnel to its pre-fire condition and analyzed the rockfall hazard from the bluff. Rock scaling was recommended as mitigation, and ODOT was able to expedite a majority of the rock scaling efforts ahead of tunnel construction.

The fire destroyed the tunnels interior timber canopy and waterproof membrane, and shotcrete experienced inconsistent damage. The rock dowels survived the fire and retained their integrity. The asphalt surface and timber tunnel portals were destroyed and needed to be replaced. Complying with the Columbia River Gorge National Scenic Area standards and recreating the historic look of the original tunnel created challenges that the team overcame through collaboration.

The tunnel reopened in spring of 2021, and is serving the community and tourists once again.

鈥淐ollaboration and progressive technologies were the main contributors to the success of the project. We are sincerely grateful for services and participation from all key project partners that led to safely reopening the historic Oneonta Tunnel for recreational use,鈥� wrote Thomas Braibish, ODOT, and Matthew Miller, WFLHD, in recommending the project for ACEC recognition.