Corps invites public comments on Twin Bridges streambank stabilization Environmental Assessment

Published Aug. 20, 2012

RIRIE, Idaho – The U.S. Army Corps of Engineers Walla Walla District invites public comments on a Twin Bridges streambank stabilization project environmental assessment (EA). Comments are due by Sept. 3, 2012.

The Corps proposes to design and construct a streambank stabilization project on the South Fork of the Snake River between Rexburg and Ririe, Idaho, in cooperation with the project sponsor, Madison County, Idaho. The proposed design would protect the southern approach to the Archer Highway North Twin Bridge where the river channel has migrated south and threatens to undermine the bridge during high river flow events.

The Corps invites public comments on an environmental assessment that evaluates alternatives for the project and documents the environmental effects of the project. The EA will also determine if an environmental impact statement (EIS) is necessary. The EA and draft Finding of No Significant Impact are available at

Due to changing river conditions, severe erosion is occurring at the North Twin Bridge on the south bank and bridge abutment. This increased erosion threatens the stability of the bridge. The Corps proposes to armor the southern approach of the North Twin Bridge. The armor would span 900 feet along the upstream side of the highway and 100 feet along the downstream side of the highway.  In addition, sheet piling would be used to protect the south bridge abutment beneath the bridge.

Public comments can be emailed no later than Monday, Sept. 3, to; faxed to 509-527-7807; or mailed to U.S. Army Corps of Engineers, Environmental Compliance Section, RE: Twin Bridges EA, 201 North 3rd Ave., Walla Walla, WA 99362 by that date.

Additional information also may be obtained from Corps Project Manager Alex Colter at 509-527-7254.


Public Affairs Office

Release no. 12-076