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US-23 Flex Route Phase 2 Project

Learn more about the US-23 Flex Route Phase 2 Project.

  • MDOT has received bids for the project during the March 2023 letting. Construction is anticipated to start in the spring 2023. The work will be performed over three construction seasons. The project is scheduled to be fully open to traffic in 2026 depending on weather and other factors.

  • The project will be funded with a combination of Rebuilding Michigan and Federal Highway Administration funds.

  • The speed limit is 70 mph for the US-23 Flex Route. The speeds shown above the lanes are advisory speeds or “recommended” speeds based on areas of restricted sight distance when the shoulder is being used as a travel lane. The effectiveness of the advisory speed system is being reviewed and MDOT expects to make some improvements in this area over the next few years. However, it is still unknown whether the 60 mph advisory speed will remain in place whenever the shoulder is open to traffic.

  • The MDOT Statewide Transportation Operations Center (STOC) monitors traffic continuously throughout the day and opens the Flex Lane when criteria are met. MDOT Safety Service Patrol also monitors the corridor to confirm the Flex Lane is clear and safe to open. The Flex Lane will be open during morning and afternoon peak periods in the peak direction only for southbound from 6-9 a.m. and northbound from 3-7 p.m.

    In addition to peak periods, the Flex Lane may be opened if vehicle travel speeds decrease and traffic volumes increase, meeting conditions for a defined duration. Because it takes time to implement safety protocols before opening and closing the Flex Lane, it is not practical to open lanes to address brief intermittent periods of congestion.

    There have been several occasions where the southbound Flex Lane has been opened during the afternoon peak period due to congestion. The STOC will continue to monitor the afternoon congestion and will open the southbound direction when it is safe to do so.

  • Park and Ride lots are not intended to be trailheads for recreational use. Park and Ride lots were sized to meet commuter traffic parking needs.

  • If Winans Lake Road went directly into the Silver Lake Road roundabout, it would increase congestion at the roundabout and reduce safety by adding conflict points between vehicles, pedestrians, and bicyclists. This would also result in impacts to adjacent properties.

  • Work on Lee Road is limited and modifications to address pedestrian safety and bicycle access falls outside of the scope of work for this project.

  • The proposed path included in the project will be 10 feet wide and will accommodate pedestrians and bicycles.

  • Multi-use trail access is being provided within the limits of this project and is being designed to allow future projects to connect roads and trails outside of this project’s limits.

  • The west leg of the Silver Lake Road roundabout at Whitmore Lake Road will be a dedicated access point for the Green Oak Township Fire Department and Emergency Response. This precludes any direct connection from Legacy Road to the roundabout.

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  • The US-23 Flex Lane is designed to accommodate peak hour, higher traffic volumes, as well as incident management. The flex lane itself is an upgraded shoulder that is used as a part-time lane. Full use of the lane would require a new lane with wider median shoulders throughout the entire corridor, which would cost much more than upgrading the shoulder.

    The use of the shoulder as a lane was vetted and approved by the Federal Highway Administration and multiple coordinating agencies. MDOT was able to widen and resurface the existing roadway to build the flex lane. Building a full lane in each direction would have required the full reconstruction of the freeway. This would have had a much higher impact on the corridor at a significantly higher cost.

    The traffic pattern on US-23 has higher levels of congestion on southbound lanes in the morning with commuters traveling to Ann Arbor, while northbound US-23 traffic increases in the afternoon. These peak-hour events, as well as congestion-related crashes, drove the decision to build the flex route on US-23. The current operation is opening the southbound flex lane during the morning peak hours and opening the northbound flex lane during afternoon peak hours of traffic. Ultimately, a 24-hour fix simply is not necessary on this corridor due to the directional congestion in this area. The US-23 Flex Route increases capacity within the existing infrastructure for less money.