Mitchell Point Tunnel, Oregon—Design and Construction - NAT2024

Mitchell Point Tunnel near Hood River, Oregon is one of the more unique segments of the Historic Columbia River Highway and State Trail being constructed through the Columbia River Gorge. This 650-foot bike/pedestrian tunnel set to open in 2024 is being delivered by FHWA in partnership with Oregon DOT, Oregon State Parks, and the U.S. Forest Service. Primarily driven using drill & blast excavation methods through basalt, the shotcrete and dowel-supported tunnel features masonry portals and 􀂿ve 􀂳window adits􀂴 that provide illumination and views of the river similar to the original highway 􀂳tunnel of many vistas􀂴 built in 1915 that was removed in 1966 to make way for Interstate 84. This paper summarizes the planning, design, and construction.