Design and Evaluation of Operational Strategies for Deploying Emergency Response Teams: Dispatching or Patrolling

Both patrolling and prepositioned strategies for allocating emergency traffic response units have been implemented in practice. To compare the performance of both response strategies, this study has conducted an efficiency comparison based on the field data from the I-495/I-95 Capital Beltway. The extensive experimental results have revealed that the effectiveness of those response strategies varies with some critical factors, including the spatial distribution of incident frequency over different times of a day, the fleet size of the response team, the congestion level, and the available detection sources. In view of the resource constraints, the study has further presented a methodology to determine the most cost-beneficial fleet size operated with the proposed strategies, considering the marginal cost and the benefit of an additional response unit on the resulting total social benefits. The analysis results with the data from the Capital Beltway could serve as the basis for highway agencies to review and optimize their incident response and management program.