North Fork Swift Creek Re-Route Feasibility

A deep-seated landslide in an unusual geologic formation in the Swift Creek basin produces huge volumes of sediment with potentially hazardous concentrations of asbestos and heavy metals. Whatcom County developed the Swift Creek Sediment Management Action Plan to address this problem. One element of that plan is to assess the feasibility of diverting the North Fork away from the contaminated South Fork. This would keep the North Fork water free of hazardous sediment and reduce the volume of hazardous sediment that could be transported by the South Fork.

Role / Services: Whatcom County retained WSE to first assess the feasibility of re-routing the North Fork and then, if it proved to be feasible, develop a design to accomplish it. There are several potential routes that the North Fork could take, but all potential routes will involve crossing privately-owned land and a high-pressure gas pipeline. To complete this analysis, WSE put together a team that includes experts in public outreach, real estate, and permitting as well as engineers and geologists to assess both the technical and non-technical aspects of this complicated project.

Outcome: The analysis concluded that re-routing the North Fork is technically feasible, but faces several difficult and expensive challenges. As a result of these challenges, even the least expensive route is cost prohibitive.