Implementing the FHWA Quick Response Freight Model in the Twin Cities Steve Wilson and Jonathan Ehrlich SRF Consulting Group, Inc. SRF Consulting Group, Inc. Dan Beagan Cambridge Systematics, Inc. Presented to Tenth Transportation Research Board Planning Applications Conference Planning Applications Conference

Twin Cities Regional Freight Planning Model Objectives Objectives Approach/Methodology Approach/Methodology Calibration Considerations Calibration Considerations Applications Applications

Objectives of the Project Improve New Regional Travel Demand Models Improve New Regional Travel Demand Models Better Reflect Impact of Trucks on Traffic Flow Better Reflect Impact of Trucks on Traffic Flow Lay Groundwork for Multimodal Freight Analysis and Modeling Lay Groundwork for Multimodal Freight Analysis and Modeling Connect to Statewide Freight Plan Connect to Statewide Freight Plan

Approach Based on FHWA Quick Response Freight Manual (1996) Based on FHWA Quick Response Freight Manual (1996) Make use of local data Make use of local data Make use of limited resources Make use of limited resources

Zonal Data Employment Categories: Agriculture, Mining, Construction Manufacturing, Transportation, Communication, Utilities, Wholesale Trade Retail Trade Office and Services

Zonal Data Employment Data Employment Data Census vs. ES202 Freight Facility Inventory Freight Facility Inventory Quality Control Issues

Network Data Highways Highways ProhibitionsProhibitions GradeGrade Vehicle Classification CountsVehicle Classification Counts Navigable Waterways Navigable Waterways Terminal LocationsTerminal Locations Locks and DamsLocks and Dams Railways Railways At-Grade CrossingsAt-Grade Crossings Intermodal TerminalsIntermodal Terminals

Other Data Freight Analysis Framework Freight Analysis Framework National Freight Flow DatabaseNational Freight Flow Database Growth Rates for External TripsGrowth Rates for External Trips External Origin-Destination Survey External Origin-Destination Survey Distribution of External TripsDistribution of External Trips

Other Data Light Commercial Vehicles Light Commercial Vehicles In the regional model (large portion of NHBW trips)In the regional model (large portion of NHBW trips) Difficult to quantify either in vehicle classification counts or in home-interview surveysDifficult to quantify either in vehicle classification counts or in home-interview surveys MnDOT Light Commercial Vehicle Study, 1999MnDOT Light Commercial Vehicle Study, 1999

Four Step Model: Trip Generation By Vehicle Classification from QRFM By Vehicle Classification from QRFM Single UnitSingle Unit CombinationCombination ‘Light Commercial’‘Light Commercial’ Function of Employment Type Function of Employment Type External Trips based on External Station Vehicle Classification External Trips based on External Station Vehicle Classification Special Generator Capability Special Generator Capability

Four Step Model: Trip Distribution Default gravity model friction factor curves from QRFM Default gravity model friction factor curves from QRFM Modify trip table using matrix estimation Modify trip table using matrix estimation Adjusted default curves based on estimated matrix Adjusted default curves based on estimated matrix

Four Step Model: Time of Day Matches 24 time periods from Regional Model Matches 24 time periods from Regional Model Constant factors for each time period for each vehicle classification Constant factors for each time period for each vehicle classification Based on 24-hour vehicle classification count data Based on 24-hour vehicle classification count data

Four Step Model: Assignment Regional Model Assignment Regional Model Assignment Equilibrium AssignmentEquilibrium Assignment 24 Time Periods24 Time Periods Five Assignment Purposes Five Assignment Purposes SOV, LCV, HOV, SU, CMBSOV, LCV, HOV, SU, CMB Three Paths Three Paths SOV/LCV, HOV, TruckSOV/LCV, HOV, Truck Passenger Car Equivalency Passenger Car Equivalency

Validation Highway Link Volumes Highway Link Volumes VMT VMT

Calibration Considerations Data Availability Data Availability Vehicle ClassificationVehicle Classification Internal Origin-DestinationInternal Origin-Destination Trip Length DistributionTrip Length Distribution External Station DataExternal Station Data Commodity DataCommodity Data Concurrent Regional Model Calibration Concurrent Regional Model Calibration Regional Scope Regional Scope

Applications Forecasting Truck Traffic Forecasting Truck Traffic Pavement DesignPavement Design Development ImpactsDevelopment Impacts System Level Responses System Level Responses Modal Shift ImpactsModal Shift Impacts Value of Time/Benefit-CostValue of Time/Benefit-Cost Truck Impacts on Congestion Truck Impacts on Congestion Grade Crossing Analysis Grade Crossing Analysis

Recommendations for Further Improvement Commercial Vehicle Tracking Survey Commercial Vehicle Tracking Survey National/Multi-State Commodity Flow Model National/Multi-State Commodity Flow Model External Truck Intercept Survey External Truck Intercept Survey Vehicle Classification Data Vehicle Classification Data

Questions?