Active Traffic Management
Part-Time Shoulder Use
Part-time shoulder use (PTSU) is a transportation systems management and operations (TSMO) strategy to alleviate congestion and increase system reliability by adding capacity at the times when it is most needed. The strategy involves modifying the number of lanes available for travel in response to heavy traffic or other conditions that necessitate increased throughput.
There are three main categories of PTSU strategies:
- A Static PTSU strategy sets predetermined hours when shoulder lanes are open to vehicles.
- A Dynamic PTSU strategy responds to real-time traffic conditions when making the determination for opening shoulder lanes to vehicles.
- A Bus-on-Shoulder strategy opens shoulders to only authorized buses.
FHWA Reports and Publications
- Use of Freeway Shoulder for Travel -- Guide for Planning, Evaluating, and Designing Part-Time Shoulder Use as a Traffic Management Strategy
- Decision Support Framework and Parameters for Dynamic Part-Time Shoulder Use: Considerations for Opening Freeway Shoulders for Travel as a Traffic Management Strategy
- FHWA Specialty Lane Summary
- Public Roads: Providing a Shoulder to Drive On
- Efficient Use of Highway Capacity Summary: Report to Congress
Webinars
National Operations Center of Excellence
- Decision Process for Dynamic Operation of Part-time Shoulder Use (2019)
- Maximizing Capacity: New Applications for Full-time and On-demand Hard Shoulder Running (2017)
- Hard Shoulder Running (2016)
Transportation Research Board
- TRB: Part-Time Shoulder Use (2017)
Other Resources
Information Briefs and Case Studies
- I-55 Bus on Shoulder Demonstration
- I-66 Highway Uses Smart Shoulder to Move Traffic
- MnDOT: Bus-on-Shoulder Operating Rules
- NOCoE: US Route-1 Hard Shoulder Running
- NOCoE: Emergency Shoulder Use During Hurricane Irma
Fact Sheets
Reports
Other
Other State PTSU Projects
Washington State Department of Transportation (WSDOT): Peak-Use Shoulder Lanes
WSDOT is opening peak-use shoulder lanes in strategic areas throughout the state. This construction approach allows WSDOT to add more space for travelers more quickly and cost-effectively than expanding highways.
Ohio Department of Transportation (ODOT): I-275 Smart Lane
ODOT is widening the median shoulders of I-275 between U.S. 42 in Hamilton County and State Route 28 in Clermont County and widening the bridges over the Little Miami River to accommodate a SmartLane. The shoulder will include multiple sign support trusses for the signage needed to use the SmartLane and dynamic speed control.
State of Wisconsin Department of Transportation: Dynamic Part Time Shoulder Use (DPTSU)
The State of Wisconsin Department of Transportation is designing a DPTSU that would utilize the Beltline's median (inside) shoulder lanes in each direction between I-39/90 and Whitney Way. The design includes the installation of dynamic overhead messaging to display when the lane is open and closed. The lanes are set to be open during peak travel times, special events, and incidents.
Colorado Department of Transportation (CDOT): I-70 Westbound Peak Period Shoulder Lane
CDOT is constructing a managed toll lane on Westbound I-70 Mountain Express Lane, along the westbound lanes of I-70 from the Veterans Memorial Tunnels to the Empire interchange. The 12-mile long managed lane will feature traffic management systems to improve mobility and provide westbound drivers with a reliable, time-saving option during peak travel periods.
Hawaii Department of Transportation (HDOT): Shoulder Lane on H-1 Freeway Eastbound
HDOT opened a shoulder for use as a lane of travel during the morning commute hours. The shoulder lane is on the H-1 Freeway eastbound and begins after the Kualakai Parkway on-ramp to the Kunia/Waipahu/Ewa off-ramp, Exit 5. The shoulder is open on weekday mornings, excluding holidays.
