Road Bulkhead

Bank Failure Protection Team

Isabel Loe, Jason Leman, Michael Gonia, Chris Boodey

Advisor:  Dr. Noel Bormann

Liaison:  Greg Lahti

Sponsor: Washington State

Project Description .This project involves the analysis and design for a bank protection system that is currently failing along a steep slope of State Route 231 near Reardan, Washington.  The project sponsor, the Washington State Department of Transportation (WSDOT) wants to prevent a possible road failure due to the slope instability by designing a solution before the current bank protection system exhibits total failure. 

An important feature of the project is the difficulty of construction within the stream channel and meeting applicable permit requirements.  Currently the bank protection system consists of perforated metal plates that may have been previously used as a temporary runway surface, and driven in the ground, and tied-back with cables. 

This existing wall is exhibiting failure from the force of the soil on the bank that is bending the wall about its base.  The goal of this project is to provide WSDOT with a hydraulics report of the site, alternative solutions to the bank failure problem, and a preferred alternative. 

In addition, a list of permits required for the project, as well as cost estimates for each alternative, make up the project deliverables.  For this project, the final preferred design alternative is a system of stacked rip-rap.