FLINT TWP. — The Michigan Department of Transportation (MDOT) plans to begin work July 6 on a traffic roundabout on Bristol Road near the I-75 interchange, with completion targeted for October 22.
The $3 million project involves building the circular lanes to direct traffic in a controlled counter-clockwise movement onto and off freeway ramps and traveling east and west on Bristol Road.
The planned roundabout will include a separate “slip” freeway access ramp for traffic coming from the nearby General Motors plant and also will eliminate the need for two traffic signals in the area, said Larry Doyle, manager of the MDOT Transportation Service Center, in a recent presentation at the Flint Township Board meeting.
Funded by a combination of Traffic and Safety funds and Congestion Mitigation and Air Quality Improvement funds, the project qualified based on a total of 144 crashes within a 5 year period, including 88 angle crashes, Doyle said.
Existing safety issues include:
•The I-75 bridge obscuring the signals for EB Bristol Road
•Signal Wash-out for WB Bristol road
•Poor signal progression due to tight signal spacing
•Confusion for the traffic eastbound on Bristol Road to NB I-75 with the right lane making a loop back around to the same signal.
Currently, driver confusion is compounded by two loop ramps serving eastbound Bristol to northbound I-75 traffic and eastbound Bristol to the GM Plant.
Previous remedies implemented to reduce angle crashes included installation of low-level signals for eastbound Bristol Road traffic, installation of advanced signing (with flashers) for eastbound Bristol and improved lane assignment signing.
The proposed roundabout will incorporate the GM drive and the eastbound Bristol to northbound I-75 ramp; eliminate the need for 2 signals, reduce conflict points and crashes; lower overall delays; and accommodate large truck traffic.
It should also reduce emissions due to less vehicle stacking at traffic signals.
The proposed roundabout is projected to operate efficiently for the next 20 years during peak traffic, according to a model created by MDOT’s Geometric Unit. A simulation analysis showed that the roundabout out-performed the current signalized intersection in both capacity and safety.
Doyle said that MDOT engineers worked closely with GM and Bishop Airport officials to create a construction plan that will accommodate operations.
Construction will include closing the northbound I-75 ramp for a maximum of 14 days and a work stoppage over the Labor Day weekend in early September.
Access to GM Drive (David Street) will be maintained at all times and at least one lane of traffic will remain open in each direction on Bristol Road.
Signs will be posted during the construction period to reroute traffic while the ramp is closed and also to alert airport travelers to take alternate routes.