Transportation Management Plan Effectiveness Framework and Pilot
Chapter 1. Introduction
Overview of Transportation Management Plans
A Transportation Management Plan (TMP) lays out a set of coordinated transportation management strategies and describes how they will be used to manage the work zone impacts of a road project. The scope, content, and level of detail of a TMP may vary based on the State or local transportation agency's work zone policy, and the anticipated work zone impacts of the project. In some cases, a regional TMP may be developed to better mitigate the combined effects of several projects occurring within a corridor or roadway network. The requirements and guidance on developing and implementing TMPs exists elsewhere. (1,2)
Although TMPs are required for all federal-aid projects, those projects deemed as "significant" require a comprehensive TMP consisting of the following:
- A temporary traffic control (TTC) plan to address traffic safety and control needs through the work zone.
- A traffic operations (TO) component to address sustained operations and management of the work zone impact area (which can extend a substantial distance away from the actual project location).
- A public information (PI) and outreach component to address communication needs with the public and concerned stakeholders.
Under each of these items, two to four categories of strategies have been identified to help mitigate the impacts of the work zone. For example, three categories of strategies have been identified for possible use when developing the TTC plan:
- Project control strategies.
- Traffic control strategies.
- Project coordination, contracting, and innovative construction strategies.
Two categories of strategies have been identified for the public information and outreach component of the TMP:
- Public awareness strategies.
- Motorist information strategies.
Finally, four main categories of TO component strategies could be considered for implementation:
- Demand management strategies.
- Corridor/network management strategies.
- Work zone safety management strategies.
- Traffic incident management and enforcement strategies.
Within each of these categories, 11 to 19 individual strategies exist which could be implemented to help mitigate the safety and mobility impacts of a work zone. Table 1 through Table 3 present a compilation of the various strategies that can be used to mitigate work zone impacts. (2)
|Control Strategies||Traffic Control Devices||Project Coordination, Contracting, and Innovative Construction Strategies|
a Strategy added since publication of (2).
|Public Awareness Strategies||Motorist Information Systems|
a Strategy added since publication of (2).
|Demand Management Strategies||Corridor/Network Management Strategies||Work Zone Safety Management Strategiesa||Traffic/Incident Management and Enforcement Strategies|
Some strategies are relatively minor in cost and implementation effort required, whereas others are more costly and require much more effort to implement. Many of the strategies listed under the TTC plan -Traffic Control Devices category are actually required through national and state standards, although some work zones might benefits from additional devices above and beyond the minimums called for in those standards. In some cases, the effectiveness of a strategy is independent of the implementation of any other strategies. However, in many other cases, the effectiveness of a particular strategy is dependent upon other strategies that are implemented. In addition, many strategies can have similar effects upon driving behavior, and thus similar potential mitigation benefits, under certain roadway, traffic, and work zone conditions.
Challenges to Developing Work Zone Transportation Management Plans
Ideally, a practitioner developing a TMP would choose those mitigation strategies that provide the best benefit-to-cost effect in terms of mitigating work zone impacts. This would be done in conjunction with an impacts analysis performed as part of the TMP development process. (3) Unfortunately, information on the actual effectiveness of many of the TMP strategy is lacking. Very few agencies evaluate how well their impacts analysis results compare to what actually happens in the field, let alone assess how well the mitigation strategies employed affected the impacts of the work zone. Even for those strategies for which some assessments have been performed, the methods used and measures-of-effectiveness (MOEs) evaluated have varied widely, making it difficult to draw conclusions about how well the strategies would work as part of the TMP for an upcoming project.
Certainly, there would be value to establishing a clear, consistent approach towards assessing the effectiveness of TMP strategies. This would assist analysts charged with quantifying the actual benefits of strategies implemented, as well as those who are charged with developing TMPs for future projects. Optimally, a set of performance metrics can then be established that would be transferable from one location to the next so that agencies could learn from each other's experiences and confidently apply estimates of strategy effectiveness in their impacts analyses during TMP development.
Organization of this Report
The remainder of this report provides guidance on assessing the effectiveness of TMP strategies. First, the MOEs appropriate for evaluating how the various TMP strategies affect work zone impacts are presented. A discussion of common interdependencies between the individual strategies used in a TMP is also provided to help practitioners better understand evaluation limitations that exist in some instances. Next, an overall framework is presented regarding the types of evaluations possible of the effectiveness of TMP strategies, and methods available for performing those different types of evaluations. A compilation of previous literature regarding TMP strategy effectiveness relative to the analysis framework is then presented, followed by an examination of the approach taken to develop and then assess the impacts of a TMP implemented on a recent major rehabilitation project in North Carolina.Previous | Next