Madison County Madison County Travel Demand ModelTravel Demand Model

Challenges and InnovationsChallenges and Innovations

Diane B. Zimmerman, PEDiane B. Zimmerman, PE

Location MapLocation Map

Madison CountyMadison County

Base Year 2000Base Year 2000– 2000 Population = 70,8722000 Population = 70,872– 2000 Employment = 36,2002000 Employment = 36,200

Future Year 2025Future Year 2025– 2025 Population =105,0002025 Population =105,000– 2025 Employment = 57,0002025 Employment = 57,000

TAZ MapTAZ Map

Combined the Combined the areas from the areas from the previous previous Richmond and Richmond and Berea ModelsBerea Models

176 Internal 176 Internal ZonesZones

16 External 16 External StationsStations

Richmond and BereaRichmond and Berea

Highway NetworkHighway Network

Imported from KY Imported from KY GIS coverage the GIS coverage the Traffic Flow layerTraffic Flow layer

Added the Federal Added the Federal Functional Class Functional Class LayerLayer

Added the Local Added the Local LayerLayer

Traced Interstates Traced Interstates and ramps from the and ramps from the DOQQDOQQ

Highway NetworkHighway Network

Coded signal locationsCoded signal locations Coded g/c ratios from sketch planning Coded g/c ratios from sketch planning

of signal timingof signal timing Capacity was computed link by link Capacity was computed link by link

rather than by area/facility by rather than by area/facility by TransCAD using procedures from TransCAD using procedures from NCHRP NCHRP

Default properties were by area, then Default properties were by area, then location specific data was addedlocation specific data was added

Trip GenerationTrip Generation

Population Data from Census Block data Population Data from Census Block data Employment Data from Employment Services, Employment Data from Employment Services,

supplemented by phone calls to non-profit supplemented by phone calls to non-profit organizations and missing employersorganizations and missing employers

NCHRP 365 procedures were usedNCHRP 365 procedures were used E-I trips were converted to Productions at the E-I trips were converted to Productions at the

External stations and Attractions to Internal zonesExternal stations and Attractions to Internal zones Student Trip rates were initially taken from the Student Trip rates were initially taken from the

Lexington study and increased during calibrationLexington study and increased during calibration A separate trip rate was used for Urban and Rural A separate trip rate was used for Urban and Rural

zones to reflect trip chaining in the urban areaszones to reflect trip chaining in the urban areas

ChallengesChallenges

Two distinct small urban areasTwo distinct small urban areas Two Universities – Eastern Kentucky Two Universities – Eastern Kentucky

University and Berea CollegeUniversity and Berea College Interstate 75Interstate 75 Army munitions baseArmy munitions base Major improvement to KY 52 westMajor improvement to KY 52 west New interchange on I-75New interchange on I-75

InnovationsInnovations

User InterfaceUser Interface– Allows user to exactly replicate run Allows user to exactly replicate run

made by JJG, similar to the MINUTP made by JJG, similar to the MINUTP 00.bat file00.bat file

– Changes are made to the GISDK Changes are made to the GISDK code or to the input filescode or to the input files

User InterfaceUser Interface

Calibration ResultsCalibration Results

Overall RMSE = 26.0%Overall RMSE = 26.0% VMT Difference = -0.9%VMT Difference = -0.9%

– Urban -5.3%Urban -5.3%– Rural 2.8%Rural 2.8%

RMSE ComparisonRMSE Comparison

Interstate Prin. Art Min. Art. Maj. Coll. Min. Coll. Interstate Prin. Art. Min. Art. Collector

Functional Class Overall 1 2 6 7 8 11 14 16 17Number of Links 525 4 14 34 58 124 6 46 98 76

Total Volume 1777349 104186 69502 71486 129527 69954 143274 403262 454716 146779

Total Count 1918350 102400 78000 74800 141000 79650 137000 434500 487900 182800

Total Ratio 484.06 4.07 12.55 32.14 51.05 118.45 6.33 42.13 93.43 66.75

Total Difference 318267 1786 10520 7290 23061 21786 12086 51354 82712 69179

Total Difference Squared 473785777 960610 10269172 3234708 20290159 9784756 26897928 111391606 107281388 120370457

Average Volume 3385 26047 4964 2103 2233 564 23879 8767 4640 1931

Average Count 3654 25600 5571 2200 2431 642 22833 9446 4979 2405

Average Ratio 0.92 1.02 0.90 0.95 0.88 0.96 1.05 0.92 0.95 0.88

Average Difference 606 447 751 214 398 176 2014 1116 844 910

Average Diff. Squared 902449 240153 733512 95138 349830 78909 4482988 2421557 1094708 1583822

Root Mean Square Error 26.00% 1.91% 15.37% 14.02% 24.33% 43.73% 9.27% 16.47% 21.02% 52.32%

Calibration Summary

Rural Links Urban Links

VMT ComparisonVMT Comparison

FC Funtional Class - Description

2000 HPMS DVMT

CALIB RUN 12

Current Percent

Difference

1 Rural Principal Arterial - Interstate 612,000 665,829 8.8%2 Rural Principal Arterial - Other 98,000 113,394 15.7%6 Rural Minor Arterial 117,000 118,091 0.9%7 Rural Major Collector 234,000 225,513 -3.6%8 Rural Minor Collector 124,000 95,743 -22.8%9 Rural Local Road1 138,000 81,968 -40.6%11 Urban Principal Arterial - Interstate 484,000 516,353 6.7%12 Urban Principal Arterial - Freeway/Expway 0 014 ` 231,000 207,944 -10.0%16 Urban Minor Arterial 197,000 180,677 -8.3%17 Urban Collector 93,000 46,533 -50.0%19 Urban Local Street1 96,000 81,660 -14.9%

Rural Total 1,185,000 1,218,570 2.8%Urban Total 1,005,000 951,507 -5.3%

Total 2,190,000 2,170,077 -0.9%

Special Thanks to Nick Special Thanks to Nick Uhren for all his work!Uhren for all his work!