Kentucky Statewide Travel Model (KYSTM) Rob Bostrom Wilbur Smith Associates Combined Kentucky-Tennessee Model Users Group Meeting Bowling Green, KY

Transcription

1 Kentucky Statewide Travel Model (KYSTM) Rob Bostrom Wilbur Smith Associates Combined Kentucky-Tennessee Model Users Group Meeting Bowling Green, KY October 26, 2006

2 Presentation Overview Overview of statewide model synthesis Kentucky s statewide model history Overview of recent Kentucky statewide model development

3 Statewide Travel Forecasting Study origins Suggested by this committee Models NCHRP studies: Panel members TRB Program Manager Jon Williams Other: G. Giamio, R. Bostrom, J. Dunbar, H. Shen, D. Hunt, B. Gorman,B. Upton, M. Duross, H. Miller Schedule Selection meeting in winter, 2005 in D.C., selected Alan Horowitz of UWM Draft review meeting in July, 2005 in O.C. Final draft in editorial process

4 Study Highlights Survey of Statewide Travel Forecasting Practice Rural forecasting States doing statewide modeling Rationale Barriers Hardware/software Model usages Passenger/freight LU/Economic activity Statewide/urban integration Validation Post-processing Case Studies: KY, IN, OH, VA, WI Findings and Research Recommendations

5 Methodology Peer Exchange Reporthttp:// Surveys Screening questionnaire sent to all states Full questionnaire for states not participating in the Peer Exchange

6 Passenger Models Wide range of approaches Integrated models Ohio Oregon

7 Freight Models Trend towards commodity based, e.g. WI Generation Total Tons Distribution Tons by O-DO Truck Shares & Payloads O-D D Trucks Truck Assignment Trucks by Route

8 Findings Recent evolution of Statewide Travel Forecasting Models Network detail, commodity based freight, GIS networks, equil. assn.s Challenges ATS not updated, 24-hr. assn.s, transferable parameters not developed, little integration of urban/statewide, county-level data still used Recent Innovative Efforts Nested zone structures, integration of freight/passenger/econ., tourbased components,

9 Recommendations Four main research recommendations (from Peer) Rural Area Trip-making characteristics Development of a national passenger travel model Development of validation performance standards Long distance travel data collection State of practice suggests: Improvements in traffic assignment Intermodal freight networks Better info for non freight commercial vehicles Better public source commodity flow info Innovative means of ODME Improved curricula for trans. Planning graduate programs

10 Kentucky s Statewide Model History First model (1975) Study design by Alan Voorhees Planpac Work performed in-house Used for system needs Second model (1991) Limited update Features: triptable, in-state zones, MinUTP WSA performed work

11 Kentucky s Statewide Model Third model (1996) History Expanded zone system (1400 total, 700 in-state) First attempt at truck modeling, used matrix estimation Data sources: NPTS, Census, Transearch Impetus for model: I-66 Corridor Study Software: MinUTP Vendor: WSA 1999 corridor validation for additional I-69 study & new I- 66 alternatives

12 Kentucky s Statewide Model History Current model (2006) Expanded zone system (4870 total, 3651 in-state) Improved truck modeling, based on commodity flows Data sources: NPTS, Census, Transearch Impetus for model: corridor studies, freight needs, input from Stakeholder Meeting Software: TransCAD Vendor: WSA

13 Kentucky s Statewide Model Current model (2006) Combined zone system (2002) Version 1.0 Version 2.0 Future Enhancements Freight Interface History

14 2006 KYSTM: Goal Statement to develop a set of computerized mathematical and data management procedures ( model ) that will: Replicate existing intercity car and truck movements on major roads in Kentucky. Forecast alternative intercity car and truck movements likely to occur Generate reproducible model outputs, that can be easily understood Does not try to replicate volumes in urban areas.

15 Intercity not intracity

16 Model Framework Two inter-related models were used to forecast statewide traffic: A Macro Model covering all 48 contiguous states. 100,579 miles of total highway miles A Micro Model covering only Kentucky but at a much more detailed level than the Macro Model. 27,874 miles of KY highway miles 1,490 miles of double-lined routes 406 miles of ramps The two models are integrated.

17 Macro Model Network

18 Micro Model Network

19 Model Framework The Macro Model forecasts longer distance auto and truck travel to, from, through and within Kentucky. The Micro Model forecasts shorter distance auto and truck travel within Kentucky. The Final Model integrates both types of trips and forecast total auto, total truck, and total vehicle travel within Kentucky.

20 Trip Categories Truck Trips Long Distance Truck Trips Local Truck Trips Private Occupancy Vehicles (POV) Trips Short distance (<100 miles) Home Based Work (HBW) Home Based Other (HBO) Non Home Based (NHB) Long Distance Business Tourist Other

21 Truck Trips Base Year Long Distance Truck Trips Source: Transearch Database. Disaggregate County/BEA level data to Zone level using employment. (for each STCC) Convert Tons to Trucks. Local Truck Trips Calculated using an ODME procedure in order to calibrate to Truck Counts.

22 Truck Trips

23 HBW Trips Base Year Coverage: Intrastate and Interstate with one end in Kentucky Sources: Census Journey to Work data 2001 NHTS Methodology: Developed cross classification trip generation rates (Claritas Area Type and MSA Size) from NHTS and TransCAD QRM regression equations. Distributed based on the JTW data.

24 HBO and NHB Auto Trips Base Year Source: 2001 National Household Travel Survey (NHTS) Methodology: Developed trip generation rates. Distributed using Gravity Model. Includes HBO and NHB auto trips to and from adjacent counties. (External Stations) Eliminated any trip > 100 miles. Developed K Factors during calibration. Developed average auto occupancy from NHTS. Apply to obtain auto trip tables for HBO and NHB.

25 Long Distance POV Trips Base Year Coverage: Interstate Auto trips to, from, and through Kentucky and long distance intrastate auto trips. Purposes: Business, Tourist, Other. Sources: 1995 American Travel Survey (ATS). Methodology: Interstate: Expand ATS to develop 1995 trip tables. Intrastate: Expand ATS to develop 1995 trip tables. Verify that trip length > 100 miles. Develop growth factors based on socio-economic growth and fratar to 2003.

26 Traffic Assignment Base Year Assign trucks first using All or Nothing (AON) Assign all POV together using User Equilibrium (UE) Preload Trucks. Use calculated capacity. Use standard BPR curve to adjust for congestion.

27 Calibration Results Base Year 1. VMT Comparison (count vs. estimated) by Rural Functional Class Total Traffic 2. Screenlines Results Total Traffic 3. Screenlines Results Truck Traffic 4. NCHRP Curve (Percent Deviation) 5. VMT Comparison (count vs. estimated) by Rural Functional Class Truck Traffic

28 VMT Comparison ( count vs. estimated) NO. LINKS WITH V M T VMT DISTRI. AVERAGE VOLUME_ COUNT NO CNT COUNT VMT % % FC COUNT NO CNT MILES MILES % COUNTED ESTIMATED ERROR CNT. EST. COUNTED ESTIMT RMSE RMSE RUR URB TOT

29 Screenline Locations

30 Screen Lines Validation Summary SCREEN NO.COUNT COUNT V O L U M E E R R O R TRK CNT TRUCK VOLUME TRUCK ERROR TOTAL TOT EST. LINE LINKS % COUNTED ESTIMATED DIFF. PERCENT LINKS COUNTED ESTIMATED DIFF. PERCENT LINKS VOLUME Total

31 Percent Deviation For Rural Links in Kentucky 100.0% 90.0% 80.0% 70.0% Percent Deviation 60.0% 50.0% 40.0% Maximum Desirable Deviation 30.0% 20.0% 10.0% 0.0% Counts (Thousands)

32 Future Year Model Highway Network: Can use existing network. (current approach) Modify network to incorporate existing plus committed highways. (E+C) Others Trip Tables: Most changes due to change in socio-economic (SE) data. User can use alternative SE forecasts.

33 Truck Trip Table Forecast year Developed growth factors at each zone origin and each zone destination for each STCC truck trip table and local truck trip table and applied Fratar procedure. Combined into one future (2030) LD Truck Trip Table. Intermediate years are forecasted by interpolation. Note: Truck trips are not sensitive to alternate SE forecast

34 HBW Trip Table Forecast Year Estimate growth for each zone based on household (origin) and total employment (destination) forecasts. Apply Fratar procedure to base year HBW person trip table in PA format. Balance and convert to vehicle trip table.

35 HBO and NHB Trip Tables Forecast Year Apply same methodology as base year: Trip generation using forecast year socio-economic data. Trip distribution using time from future network. Eliminate trips > 100 miles. Balance and convert to vehicle trip tables.

36 Long Distance Auto Trip Tables Forecast Year Estimate growth for each zone (one for origin, one for destination) based on socio-economic forecasts. Uses different socio-economic data depending on trip purpose. For example: Business trip Uses population growth for origin. Uses total employment growth for destination. Apply Fratar procedure to base year PA person trip tables by purpose. Balance and convert to vehicle trip tables.

37 Traffic Assignment Forecast Year Assign trucks first using All or Nothing. (AON) Assign all POV together using User Equilibrium. (UE) Preload Trucks. Use calculated capacity. Use standard BPR curve to adjust for congestion.

38 User Interface

39 User Interface

40 Questions? Rob Bostrom & Sashank Singuluri & Anne Reyner &