Potential improvements | Safety |
Project comments |
US 12/18 (Madison Beltline), Whitney Way to I-39/90 - Dane County
The Wisconsin Department of Transportation (WisDOT) is examining a range of alternatives to address deteriorating infrastructure needs in the pavement structure and median areas, and to address operational issues during weekday peak periods and unexpected congestion.
One alternative includes a resurfacing with drainage improvements and replacing deteriorated sections of the existing barrier wall.
The other alternative being considered involves all items included with the first, plus other upgrades to allow the Beltline median shoulders to be used as travel lanes. The shoulder travel lanes would open during peak periods to safely and efficiently improve travel reliability between Whitney Way and Interstate 39/90. The practice, known as part-time shoulder use, is currently in place in at least 17 states.
Part-time shoulder use is recognized as a safe, sustainable and reliable way to alleviate congestion. It allows vehicle traffic on paved shoulders during peak travel times. Changeable message signs would be used to indicate when the shoulder is available for use.
In addition to the mobility improvements, shoulder modifications:
- Minimize impacts to the environment
- Does not require real estate acquisition from adjacent properties
- Could be implemented as early as 2021
For more information on how Dynamic Part-Time Shoulder Use works, please click on "Video - How it works" located on the left side of the page.
- Experience in the U.S. to date has not identified major safety issues with part-time bus, static, or dynamic shoulder use that led to discontinuation.
- The best available predictive crash analysis tool was used for this project’s safety analysis.
- The relative analysis showed that with the activation of DPTSU, the number of predicted crashes is not anticipated to increase compared to a No-Build condition.
- Travel time reliability, as well as the average amount of time needed to travel the Beltline during peak hours, are both projected to improve significantly with Dynamic Part-Time Shoulder Use.
- Median shoulder lanes would be available during the high-volume morning and afternoon travel periods to alleviate congestion and address existing safety concerns. During off-peak hours, the shoulder would be available for recovery and emergency stopping as usual.
- The shoulder lanes could also assist with traffic operations during special events or traffic incidents.
- The sustainability of the Madison Beltline is critical to south-central Wisconsin and a priority for WisDOT, which is focused on improving and prolonging the existing system while comprehensive long-term Beltline plans are evaluated.
- Dynamic Part-Time Shoulder Use is increasingly recognized as a way to optimize the performance of existing infrastructure and improve safety and reliability of the transportation system.
- Part-Time Shoulder Use would extend the remaining life of the Madison Beltline system while addressing existing safety and operational needs.
- Evaluations indicate the pavement life of the part-time shoulder lanes would function for at least 10-15 years following implementation.
- The modifications could be made with no real estate acquisitions from properties.
- Improvements to drainage, median barrier, pavement marking, spot shoulder widening and signage would be anticipated as part of implementation of dynamic part time shoulder use.
- 2019-20 – Preliminary design
- July 24, 2019 – Public involvement meeting (PIM) to present Beltline alternatives
WisDOT welcomes comments/suggestions. Please share your feedback on the alternatives, traffic, design, public outreach and long-term planning. Thank you for your interest and assistance with this project.
Brandon Lamers, P.E.