Willow Creek Road Roundabout

Dokken Engineering provided design services to the County of Placer for the redesign during construction of the Willow Creek Roundabout. The County had contacted Dokken Engineering requesting a redesign when the client noticed problems with the grades and alignments. Dokken Engineering along with a subconsultant prepared new horizontal and vertical geometry for the roundabout in one month. The files were delivered to the County and the field crews constructed the new geometrics. The timely response by Dokken allowed the County to keep the construction moving forward.

The Roundabout is a single lane urban sized roundabout that has inside and outside truck aprons, the first time outside truck aprons have been installed in a roundabout in the County. The Roundabout serves the County offices and a local road that connects to Highway 49. Key design constraints for the roundabout included a box culvert being built under the roundabout. The box culvert restricted the vertical placement of the roundabout and required special attention as to not exceed any of the advisory grades within the roundabout itself. The horizontal location was also constrained by the ends of the box culvert and irrigation ditch serving it.