Connecting communities safely by implementing alternative solutions
At a glance
Modern Roundabouts provide a sustainable solution for intersection control. By implementing alternative intersections, such as roundabouts in high-speed approaches, we reduce speeds and mitigate high impact collision areas - providing safer commutes.
The challenge
The Ministry of Transportation required a new roundabout design to improve safety at the intersection of Highway 140 and Netherby Road in the City of Welland.
Highway 140 is a two-lane, high-traffic volume rural highway with a posted speed of 80km/h and is the primary north-south road on the east side of the Welland Canal. Netherby is a two-lane, rural road with a posted speed of 50km/h. As the location is situated along a flat gradient with relatively good sight distances, slowing the operating speeds was the priority.
Our response
Bringing together technical requirements and aesthetics, the proposed upgrade was a single-lane roundabout design with improvements to the site's approaches, drainage, illumination, and safety. We considered the technical parameters depending on vehicle speeds and traffic volumes at each entry and exit point.
We achieved speed control through the geometric design of the roundabout and its environment. Along Highway 140's high-speed approach, we created a serpentine design into the roundabout in advance of the reduced entry radius - forcing gradual speed reduction. Longer splitter islands were implemented along Highway 140 through this transitional area.
The impact
We maintained existing traffic patterns in each direction during the design process. The resulting design reduced approach speeds while alerting drivers to the upcoming roundabout by altering the driving conditions. Once completed, the City of Welland will have an aesthetically pleasing, alternative intersection control that increases road safety for Port Colbourne residents as well.
The roundabout will help in the reduction of greenhouse gases as compared to other forms of intersection control. In addition, this project contributes to a sustainable environment by extending the service life of existing functional infrastructure and minimize the amount of removals and new materials.
Coordination with the utility companies and property acquisition will be required to accommodate construction.
**The roundabout design followed specific MTO requirements, TAC Guidelines (2017) and NCHRP 672 Guide (2010) from the USA.