Active Traffic Management
Hard Shoulder Running (HSR) is an innovative traffic management strategy within the broader umbrella of Active Traffic Management (ATM) systems. It involves the dynamic use of hard shoulders, traditionally reserved for emergencies, as additional traffic lanes during periods of high traffic demand. This strategy is designed to increase road capacity and alleviate congestion without the need for extensive physical infrastructure expansions.
In HSR, the hard shoulder is converted into a live traffic lane, typically during peak hours or under conditions that predictably lead to congestion. This conversion is managed through a combination of intelligent transportation systems which include overhead gantries equipped with dynamic message signs. These signs inform drivers when the shoulder lane is open for use and when it is closed, maintaining the ability for emergency vehicles to access it if necessary.
One of the pioneering implementations of HSR can be seen along the I-670 corridor in Columbus, Ohio. Referred to as the SmartLane, this pilot project by the Ohio Department of Transportation is the first of its kind in the state. The SmartLane project utilizes real-time traffic data to regulate flow, reducing congestion and improving travel times during peak hours.
Another example is the application of HSR on Route 288 in Virginia, particularly between State Route 711 (Huguenot Trail) and Route 6 (Patterson Avenue) in the counties of Powhatan and Goochland. This use of HSR is part of a broader strategy to maximize existing road infrastructure to manage increasing traffic volumes.
Increased Capacity: By utilizing the hard shoulder as a temporary lane, roads can accommodate more vehicles, effectively reducing congestion without new lane construction.
Cost-Effective: Compared to physical infrastructure expansion, HSR requires fewer resources, making it a financially attractive solution for managing congestion.
Flexibility: HSR systems can be adjusted dynamically based on real-time traffic conditions, thus optimizing traffic flow as needed.
Safety Concerns: The primary function of the hard shoulder as an emergency lane is compromised, which can pose risks if not managed correctly.
Driver Compliance: Effective communication and enforcement are necessary to ensure drivers correctly understand and adhere to the dynamic lane changes.
Technological Dependence: The success of HSR relies heavily on advanced traffic monitoring systems and infrastructure, which require significant initial investment and maintenance.
Hard Shoulder Running is a testament to how innovative traffic strategies can enhance roadway capacity, improve travel times, and make cities more navigable, all while minimizing ecological and economic costs associated with traditional road expansions.
Active Traffic Management (ATM), also known as managed lanes, smart lanes, or managed/smart motorways, is an innovative method of enhancing peak road capacity and improving traffic flow. This system is a crucial component of the broader Intelligent Transportation Systems, specifically within the subfield known as the Advanced Traffic Management System.
ATM incorporates various technologies and strategies to optimize the use of existing roadway infrastructure:
Variable speed limits are a fundamental feature of ATM, where speed limits can be dynamically adjusted based on real-time traffic conditions. This approach helps in reducing traffic congestion and minimizing the risk of accidents by controlling the speed of vehicles traveling on the road.
Hard shoulder running is another critical element of ATM, particularly used in smart motorways in the United Kingdom. This technique involves converting the hard shoulder into a traffic lane during peak hours or in response to incidents, thereby increasing road capacity.
Dynamic lane management involves the use of overhead gantries equipped with full-color LED signs to direct traffic flow. These signs can indicate lane openings, closures, or restrictions, helping to manage traffic density and improve safety.
Several regions have successfully implemented ATM systems to tackle traffic challenges:
The M42 Motorway and the M40 Motorway are prominent examples of active traffic management in the UK. These motorways use a combination of variable speed limits, hard shoulder running, and real-time traffic monitoring to enhance road efficiency.
In the United States, the Interstate 90 in Illinois and Project Neon in Southern Nevada utilize ATM technologies to alleviate traffic congestion. The Southern Nevada Traffic Management Center employs ATM to manage traffic conditions on roads like I-15 and U.S. 95.
Active Traffic Management offers several benefits, including:
Active Traffic Management represents a shift towards more intelligent and responsive road systems, integrating advanced technologies to better serve the needs of modern transportation networks.