Land Use Planning
Civil Engineering
Transportation Engineering
Landcape Architecture

Dike Access Road I-5 Interchange Improvements
Teardrop Roundabouts Accommodate Large Truck Loads

Woodland, WA

Teardrop roundabouts were designed for both ramp terminals along with roadway and pedestrian safety improvements along Dike Access Road. The improvements met WSDOT and City of Woodland standards, and were designed to protect six existing wetland areas throughout the interchange and to preserve existing utilities within a main utility easement. Coordination efforts with the Army Corps of Engineers, Washington Department of Fish and Wildlife, the BNSF railroad, and multiple utility purveyors were necessary to bring this project to completion. For the teardrop roundabouts, PacLand utilized the WSDOT standards and evaluated the design to accommodate large truck loads which frequently utilize the interchange. A WSDOT Plan for Approval was completed and approved. The intersection was upgraded to include curb, gutter, sidewalk, and street lighting as part of the roundabout construction. Drainage design for this project included the installation of approximately 1000 linear feet of dual-30 pipes to alleviate the amount of off-site stormwater flowing over the roadway during flood conditions. In addition to this off-site by-pass system, approximately 1,500 linear feet of storm drainage conveyance systems have been designed for collection of stormwater runoff from Dike Access Road. The project will also provide stormwater treatment through the use of a biofiltration swale and media filter drains.