East Main Street & Green Coulee Road Roundabout
2023 Engineering Excellence State Finalist
Entering Firm: MSA Professional Services Inc.
Client: City of Onalaska
Onalaska’s East Main Street and Green Coulee Road intersection was overworked. Growing traffic demand placed immense strain on each road and these issues came to a head at the intersection. With major congestion and resulting crashes and other safety shortfalls, a new design was needed.
MSA Professional Services engineers determined a two-lane roundabout was the solution. A roundabout keeps traffic moving and reduces the number of crashes. With two lanes, the new intersection handles current and expected increases in traffic volume. The roundabout preserves access to adjacent businesses which was a key demand of local stakeholders. The design also increased pedestrian access and safety.
One of the biggest issues with implementing the roundabout was constraints on the size of the intersection. Major real estate acquisitions were not an option, so the design team went outside the box. By connecting nearby culverts with a retaining wall, flow for a nearby stream was enhanced and the geometry of the intersection was changed. That gave the design team the space required to implement the roundabout.
Onalaska’s newest intersection is still one of its busiest. But its new design is safer and more efficient, much to the joy of users and neighbors.