Mount Rainier National Park Initiates Flood Mitigation Planning for the White River Corridor, Seeks Public Comments on Issues to be Addressed

Date: April 18, 2012
Contact: Karen Thompson, Environmental Protection Specialist, 360-569-6507

Mount Rainier National Park Superintendent Randy King has announced that the park is initiating the preparation of an Environmental Assessment (EA) for the installation of flood mitigation structures within the White River corridor to protect State Route 410, also known as the Mather Memorial Parkway, a national scenic byway and contributing element to the park National Historic Landmark District. It is also the primary eastern access to Mount Rainier National Park. In accordance with the national Environmental Policy Act (NEPA), the EA will present alternatives for the work and analyze and disclose potential environmental impacts.

Substantial portions of the highway are located within the river valley bottom, where it has been adversely affected by recurring floods and subsequent bank erosion along the White River. Flood and erosion damages have resulted in repeated highway closures and emergency maintenance actions by Mount Rainier National Park (MORA) and the Washington State Department of Transportation (WSDOT).

The project area includes the White River and SR 410 between milepost 57.9 and milepost 60.0. Proposed activities include the installation of structures, such as buried log and rock toes, log debris walls, headcut log fills, and engineered log jams at strategic locations in the White River floodplain to provide flood protection for the road. The structures are constructed of logs and ballast rock engineered to act as a single unit. The structures farther away from the road are designed to mimic the functions of woody material within the floodplain and would act to dissipate river energy and flows, encourage deposition of sediment and create fish refuge and habitat. The structures adjacent to the road would minimize side channel erosion close to the road. The installation of the structures would include excavation within the floodplain and along the river bank, installation of the structures and backfilling around the structure. Raising the road slightly in a strategic location (a road hump) has also been proposed to protect the road downstream.

The park is inviting comments from individuals, organizations and other agencies to help identify the range of issues to be addressed in the EA, as well as potential alternatives for reducing impacts to park resources, visitor access and safety.

Those wishing to provide comments should submit them in writing to: Superintendent, Mount Rainier National Park, 55210 238th Ave. E., Ashford, Washington 98304; or electronically at https://parkplanning.nps.gov, choosing Mount Rainier National Park from the drop down menu. Please provide comments no later than May 18, 2012. Additional opportunities for public review and comment on the EA will be announced in the fall of 2012. 

Your comments, including you personal identifying information (name, address, telephone, email address)- may be made publicly available at any time, if requested under the Freedom of Information Act. While you can request your personal identifying information (name, address, telephone, email address) be withheld form public review, we cannot guarantee that we will be able to do so.

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