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The Columbia River separates the States of Oregon and Washington cutting across the Cascade Mountains creating a fantastically scenic Gorge that was named a National Scenic Area in 1986. Cape Horn in the Gorge is a massive basalt cliff outcrop composed of the Grand Ronde Basalt Flows (http://columbiariverimages.com, 2017). State Route (SR) 14 is the major east-west roadway on the north side of the Gorge in the state of WA. There are numerous watersheds draining from the gorge slopes which roads such as the SR-14 cross, one such drainage near Cape Horn has produced historic debris flows. During the 1990s a drainage was outfitted with a now obsolete debris flow net structure in the 1990s.
During the spring of 2017, a storm-induced debris flow overwhelmed the original, basic debris flow structure. The Washington State Department of Transportation (WSDOT) contacted Geobrugg North America, LLC for technical assistance to layout and design a modern flexible debris flow mitigation structure. Their analysis resulted in specifying a UX-120-H4 system from Geobrugg North America, LLC. Hi-Tech Rockfall Construction, Inc. was contracted to perform the installation work. Being the Gorge a National Scenic Area aesthetics are a major concern and required colorization of the flexible debris flow structure. Powder coating colorization was chosen by WSDOT to camouflage the system, but the exact color they specified was unavailable. Geobrugg suggested another colorization system from the company NATINA: NATINA Steel stain with a rustic brown, earth tone finish.