Evaluation of Hard Shoulder vs. Contraflow Lanes for Hurricane Evacuation Using Florida Statewide Model
Corresponding Author: Thomas Hill, Florida Department of Transportation
Presented By: Thomas Hill, Florida Department of Transportation
FDOT Central Office is studying the travel demand modeling forecasting and reporting of evacuation traffic as an input for the comparison of Hard Shoulder vs. Contraflow traffic throughput for Hurricane Evacuation in Florida. This project includes data development, use of the both the Florida Statewide Travel Demand Model and the Transportation Interface for Modeling Evacuations (TIME) Model, and requires coordination between multiple FDOT offices, personnel and consulting staff.
Results of the travel demand modeling effort will act as input variables for a more detailed comparison microsimulation model of I-75 between the Florida Turnpike to I-10. These data inputs are necessary to fully estimate the forecast demand for I-75 commuters evacuating from Pinellas, Hillsborough, Manatee and Pasco counties. It is anticipated that results of this project will establish policy guidance for the use of either contraflow or hard shoulder lane utilization.
Several steps will be developed for contraflow and hard shoulder travel demand traffic forecasts. The steps within this effort include: Execution of the TIME Evacuation model for overall demand generation; Subarea model development, calibration and system review; Methodology review and refinement; Network attribute and Scenario Development; Documentation
The requirements of this comparative study involve multiple model scenarios for the evaluation of vehicle throughput. The following scenarios are necessary in order to effectively compare throughput volumes: Base – no revisions to the network are necessary. This scenario evaluates conditions for the addition of evacuation traffic to already established travel demands; Hard Shoulder – adds lanes to the already existing model network to estimate travel throughput when both the outside and inside shoulders are activated for evacuation travel. This is projected as 24 hour availability with significantly reduced capacity for the axillary lanes as compared to the normal through lanes; Contraflow – uses the southbound travel lanes for northbound travel. FDOT policy direction limits the use of the contraflow lanes to daytime hours, it is necessary to restrict capacity to reflect the abridged travel lane availability. This will be consistent with the average daylight hours for mid-September.