What’s Happening Engineering: The preliminary engineering for the project will be starting in March 2021. County crews will be surveying the project area, and we will be starting to prepare preliminary plans.
About the Project Planned improvements to this intersection include a new mini-roundabout with mountable center and splitter islands, crosswalks, streetlighting, and cement concrete curb and gutter. Also to be considered are pervious concrete sidewalks and Rectangular Rapid Flashing Beacons (RRFB) at the new crosswalks, as well as storm drainage treatment facilities.
Why A Roundabout?
While some drivers are initially hesitant about driving roundabouts, studies show that after driving a roundabout, most people favor them over a traditional traffic signal.
Studies have also shown that roundabouts are safer than traditional stop signs or signal-controlled intersections because they require drivers to slow down to maneuver through the intersection.
At intersections with relatively lower traffic volumes, mini-roundabouts like the one planned at Golden Given Road East / 99th Street East can reduce, or avoid altogether, the additional right-of-way needed from normal roundabouts. Insurance Institute for Highway Safety (IIHS) and Federal Highway Administration (FHWA) studies have shown that roundabouts typically achieve:
A 37 percent reduction in overall collisions.
A 75 percent reduction in injury collisions.
A 90 percent reduction in fatality collisions.
A 40 percent reduction in pedestrian collisions.
Resources on Roundabouts
The Washington State Department of Transportation (WSDOT) has a fantastic web page, Roundabout Information. This web page is devoted to explaining all things "Roundabout" including a couple of brochures, references to some studies, and several videos on various roundabout related topics.
The Federal Highway Administration has published a Technical Summary explaining the unique features of mini-roundabouts.
March 2021 to December 2022: Complete the field survey, soils studies, preliminary engineering and right-of-way plans.
Beyond: Funding for right-of-way acquisition and construction has not yet been allocated. Once that is done, a schedule for further phases of the project will be determined.