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Creating an Operations-Based Travel Forecast Tool for Small Oregon Communities. TRB National Transportation Planning Applications Conference May 20, 2009 Chris Maciejewski, P.E. – DKS Associates. 10. 5. Presentation Outline. Traditional Planning Issues / Shortcomings Methodology Overview
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Creating an Operations-Based Travel Forecast Tool for Small Oregon Communities TRB National Transportation Planning Applications Conference May 20, 2009 Chris Maciejewski, P.E. – DKS Associates 10 5
Presentation Outline • Traditional Planning Issues / Shortcomings • Methodology Overview • Outcomes • Applications in Transportation Plans • Conclusions
Transportation Planning Issues in Small Communities State Highways Local Perspective • Capacity needs dominate system • More lanes • Couplet • Bypass • Reduced state funding capacity [how is this unique to small cities?] • Highway congestion 20-30 days per year • Limited matching funds for highways • Looking for solutions to protect community livability
Limitations of Traditional Methods for Travel Forecasts • Travel Demand Model Not Available • Manual Methods Exist… • Trend-line • Cumulative (TIS-style) • But They Cannot: • Consider operations • React to congestion • Evaluate multiple scenarios Unconstrained Trend-line? Congested Corridor? Volume Year
An Integrated Tool Needed to Meet All Study Requirements • Assess Corridor Management • Local Circulation Enhancement • Relief Valves For Seasonal Congestion • Balance Of Community Livability with Highway Capacity
New Elements Needed to Strengthen Forecast Process Weakness of Current Process Tool Features • Cannot dynamically assess route changes • Does not consider effects of congestion • Cost effective scenario testing • Develops trip tables to test circulation patterns • Uses node delays for assignments • Rapid Evaluation Of Alternatives
Key Methods Applied • Parcel Level Land Use • Use Of NAVTEQ Network Files • ITE Trip Rates • Simple Gravity Model • HCM Node Delays • Export Network/Volumes To Synchro/SimTraffic Forecast Process
It Looks a Model and Talks Like a Model, but it is a Forecast Tool
Quality Review Process • Calibration Exceeded Expectations • R2 = 0.98, slope = 1.03 • Reasonable turn-movements • Local circulation patterns captured • Simple Gravity Model Reasonable For Small Communities
Other Useful Results • Volume Difference Plots • Quickly summarize alternative effects • Useful to communicate changes in traffic flows • Conversion of VISUM file to Synchro/Simtraffic
Sample Application – Sisters, OR • Forecasts Responded to Corridor Congestion • Detailed Evaluation of Corridor Management Options • Visual tools facilitated participation from all interested parties • Led to City and ODOT consensus (first time in 20 years) • Corridor solution with seasonal ITS, City arterial corridor
Key Findings & Recommendations • Ability to rapidly/accurately test network changes • Graphic display tools help build consensus • Corridor Management = Fewer Unfunded Highway Projects • Most appropriate application for: • Small urban areas (less than 15,000 pop.) • Significant growth forecasts • Multiple scenarios need to be evaluated and tweaked for consensus building
What About Larger Urban Areas? • Integrate Operations Into a Travel Demand Model? • Sub-area plans • Corridor plans • Circulation studies • Utilize Travel Demand Model Trip Tables • Take Advantage of Operations-Based Assignments • Quasi-Mesoscopic Sub-Area Model Forecast Process
Next Steps • Can travel times in the forecast tool (including the HCM node delays) be utilized for greenhouse gas estimations? • VMT (by speed bin) x Emissions Rate = Greenhouse Gas? • Valid for relative comparison of alternatives?
Acknowledgements • DKS Associates Staff • Carl Springer • Garth Appanaitis • Mat Dolata • Brad Coy • Oregon Department of Transportation • Transportation Planning Analysis Unit (TPAU)