The intersection of Burlington Road and Illinois Route 47 is in a rural but well-traveled section of Kane County. Burlington Road is a Kane County highway, while Illinois Route 47 is owned and maintained by the State of Illinois. For many years, there were stop signs at this intersection for Burlington Road only. Accidents in the 1990s prompted the Illinois Department of Transportation to install stop signs on Illinois Route 47 along with a flashing overhead beacon over the intersection, making the intersection a four-way stop and improving safety. After these traffic control devices were in place, accidents were significantly reduced, but vehicle delay increased.
While the four-way stop has made the intersection much safer, other issues have arisen. The increase in traffic on both roadways in recent years has led to significant backups and congestion at the intersection during rush hours. This congestion, and the prospect of more as the County continues to grow, prompted the Kane County Division of Transportation to begin looking for ways to address the congestion issue before it becomes worse.
Intersection Improvement Study (Traditional Design)
Engineering consultant Burns & McDonnell was hired by Kane County to study the intersection and propose improvements to enhance the flow of traffic flow through the intersection. It was originally anticipated that the intersection could be improved with a traditional design, including widening the existing pavement to add new left turn lanes on all four approaches, and adding a new traffic signal. Federal Congestion Mitigation and Air Quality (CMAQ) funds were secured to help pay for these improvements.
Illinois Route 47 is a State of Illinois Highway, and is classified by the State as a Strategic Regional Arterial (SRA). Roads with this classification are intended to supplement local expressways by encouraging the flow of regional traffic. Any plans to improve them must involve special design standards and additional turn lanes for more efficient traffic flow. The increase in roadway pavement needed to meet these standards included right turn lanes in addition to the left turn lanes and traffic signal originally anticipated. The additional improvements were estimated to cost more than the CMAQ grant would cover creating a funding shortfall – with the possibility that the extra costs would be paid primarily from County funds.
New Direction (Alternate Design - Roundabout)
After considering several options a roundabout was proposed instead of the traditional intersection-with-a-traffic-signal design. It was determined that a roundabout would function better than a traffic signal at this location, since vehicles only need to slow down at a roundabout instead of coming to a complete stop.
Roundabouts are a tried and true, low cost engineering solution in other states, but new to most Illinois drivers. Roundabouts are typically much safer than other types of intersections for two reasons – they reduce the speed of every vehicle traveling through the intersection, and they eliminate the right-angle and head-on collisions that cause the most harm to people and vehicles. They can also reduce congestion by decreasing stopping and waiting times. A driver can enter a roundabout whenever there’s a gap in traffic – no more waiting for a red light to turn green.
It was determined that a roundabout would function better than a traffic signal at this location. A roundabout would be more cost effective as well, since only one lane of pavement is required to enter a roundabout, compared to the three lanes (a left turn lane, a through lane, and a right turn lane) needed for a conventional intersection approach. Since the CMAQ funding can be used for a roundabout, this option would allow the County to provide a high-quality traffic improvement at the least possible cost to its residents.
Public Involvement and Design Approval
The County hosted a Public Meeting on August 18th, 2010 to give residents and travelers an opportunity to learn more about the project. Officials from Kane County were on hand to explain the process, answer questions and provide information on roundabouts and other intersection designs.
The Illinois Department of Transportation approved the design of the proposed roundabout in July of 2011.
The Kane County Division of Transportation has retained Burns & McDonnell to prepare contract plans and specifications for the roundabout. The detailed design phase began in November of 2011, and is expected to last approximately 12-24 months. Construction will occur in 2016.
Project Development Report