Elwha River Bridge | Clallam County, Washington

When the century old Elwha River Bridge required replacement, WSP engineered a structure with minimal environmental impact and enhanced nature views.

 The Elwha River Bridge, a century-old structure listed on the National Register of Historic Places, was structurally deficient and dangerously in need of replacement. Designing a replacement bridge to ensure minimal impact to the sensitive environmental areas along the river while maintaining the narrow footprint of the deteriorating bridge was a challenge. In addition, the bridge needed to accommodate the Olympic Discovery Trail, a planned 150 miles of non-motorized recreational corridor for visitors to the Olympic National Park.

Through a concerted community involvement effort, it was determined that the solution that best balanced the competing interests of cost, aesthetics, pedestrian access, and ability to minimize environmental impacts was to construct a double-decked bridge with separate vehicle and pedestrian decks. The result was a suspended pedestrian walkway below the new bridge that seamlessly connects to the Olympic Discovery Trail. Stacking the automobile deck above the pedestrian and bicycle deck ensured minimal impact to the salmon-bearing river below, while accommodating travelers and ensuring their safety and enjoyment in the area.