Evacuation Modeling Ava Damri, Calvin Smellage, Al Zinkand

Introduction Model for planning an evacuation of the Gulf Freeway area prior to a hurricane –Chain of cities from Galveston to Houston –Prospective users: FEMA, TXDoT Account for situational requirements Network flow model used for solution Model will be expanded to reflect real world complexities

Create a scalable model to minimize the evacuation time of the I-45 Corridor Test the impact of decisions involving on-ramp control, lane reversals, population distribution, and related assumptions Problem Statement

Solution 3 persons per vehicle Highway capacity of 2,400 cars per lane per hour On-ramp capacity of 250 cars per hour Flow free of traffic accidents Vehicles limited to civilian cars Approximately 10 minutes of travel time between cities Assumptions

Solution Multiperiod, Unidirectional Network Flow Model Implemented in an optimization modeling language Creates links between cities –Subdivided into time periods –Subject to on-ramp & highway capacity Based on flow conservation –Cars coming in = Cars going out Solution

Galveston (19,000 cars) Texas City (15,000) Staying Evacuating Evacuated to Houston Stranded Time 1Time 2Time 3Time 4Time 5 Multiperiod, Unidirectional Network Flow Population Pool

Galveston (19,000 cars) Texas City (15,000) Evacuated to Houston Stranded Time 1Time 2Time 3Time 4Time 5 Multiperiod, Unidirectional Network Flow Population Pool Flow ≤1,000 C=1C=10C=…C=99

Analysis No “waiting” vehicles 100% evacuation On-ramp capacity is limiting factor Southern cities given “priority” Highway system is sufficient

Full-scale, working model –Successfully evacuates populations –Expandable Accounts for: –Initial populations –Highway capacities –On-ramp capacities –On-ramp control Maximizes the number of safe people Current Functionality

Further Research –Lane reversal –Emergency vehicles –Off-ramps –Fuel coordination –Embedded safety zones –Cost scheduling Future Functionality

Apply real-world traffic data from TXDoT Incorporate results of further research Demonstrate the value of mathematical modeling in planning city evacuations Next Steps