Understanding and managing disaster evacuation on a transportation network

Area of Science:

• Transportation Engineering
• Emergency Management
• Urban Planning
• Public Health

Background:

• Uncertainty in population behavior during emergencies can severely impact transportation systems and evacuation effectiveness.
• Assessing transportation system performance requires integrating behavioral insights with travel demand modeling for effective emergency management.

Purpose of the Study:

• To analyze transportation system demand and performance under three disaster scenarios for emergency management.
• To develop and demonstrate a transferable methodology for assessing evacuation impacts on regional transportation networks.

Main Methods:

• A two-step methodology was employed: estimating evacuation trips based on survey data and assigning trips to a highway network using GIS.
• Performance measures, including volume-to-capacity ratios, evacuation times, average speeds, and traffic volumes, were generated for each scenario.
• The methodology was applied to a Washington, DC transportation network under three radiological dispersion device attack scenarios.

Main Results:

• A single detonation could degrade transportation system performance two to three times more than a typical weekday peak hour.
• Critical arterial roadways are projected to exceed capacity under the simulated disaster scenarios.
• Calculated evacuation travel times indicate that unaided evacuation is impractical for the affected region.

Conclusions:

• The findings provide crucial data for transportation managers and public health officials to develop effective countermeasures and operational adjustments.
• The methodology aids decision-making for resource allocation among various stakeholders, including infrastructure owners and planning staff.
• Integrating behavioral data into transportation modeling is essential for robust emergency preparedness and response planning.