Residents had been avoiding the intersection of Powell Butte Highway with Neff and Alfalfa Market Roads because of safety concerns due to high speeds and limited sight distances. This new roundabout on the Powell Butte Highway increases safety for the nearly 6,000 travelers and commuters who drive through the intersection each day. Given the major accidents at the intersection, including a fatality, these improvements contribute to the surrounding community in a very real way. Being the first County-led roundabout project, it will serve as a model for future, similar intersections.
Because the roundabout is located on a high-speed highway, the Parametrix team developed creative solutions to slow traffic and improve visibility for drivers approaching the intersection. Some of the methods included traffic calming measures such as a dynamic feedback sign, striping treatments, and extension of splitter medians. The design also addressed the need for high visibility on the approach legs so drivers are aware of changes ahead. Services provided by the Parametrix team included the following:
- Concept development
- Survey
- Geometric refinement and finalization
- Pavement materials assessment and design
- Drainage analysis and design
- Cost estimating
- 3D modeling
- Construction staging
The project was completed on time and within budget. Because Deschutes County desires to consider roundabouts as a traffic control device on similar intersections, it was important that this project was successful, improving safety, gaining public acceptance, and showing the public that their taxpayer dollars were spent appropriately and cost effectively. The project turned out to be a success on all fronts
