Traffic Parameters for use with MOBILE6 in Ky. - Update

by Jesse Mayes, P.E.

Division of Division of

Multimodal ProgramsMultimodal ProgramsJuly 22, 2003July 22, 2003

Air Quality Timelines

• New Emissions Model MOBILE6 - Now

• New 8-Hour Ozone Standard - 4/15/04

• Conformity due - 4/15/05

• SIP due - 4/15/07

• New PM2.5 Standard - 12/15/04

• Conformity?

• SIP due - 12/15/07

MOBILE6 Requirements

MOBILE 6.2

VMT BY TIME OF DAY

VMT BY YEAR OF VEHICLE

FREEWAY/RAMP VMT DISTRIBUTION

WEATHER

VMT BY VEHICLE TYPE

AVERAGE SPEEDS BY FUNCTIONAL CLASS OF ROAD

Traffic Parameters for use with MOBILE6 in Ky.- Update

• VMT

• Ramp %

• Speed (Space Mean Speed)

• Truck %

• Vehicle Age/Type Distribution

VMT

• HPMS data

• Local mileage GPS’ed (TBC by 12/31/03)

• Local ADT based on collector ADT (see KTC report at http://www.ktc.uky.edu)

• Forecasts developed in-house based on trends

Ramp %

• Freeway Mainline/Ramp %• Mainline % Ramp %

• MOBILE6 Default 92.0% 8.0%

•

• Kentucky Urban 92.4% 7.6%

•

• Kentucky Rural 98.5% 1.5%

•

See KYTC Report

Speed

• Starting Point

• Data Collection

• State of Speed Estimation for Areas without TDMs (Rural Areas)

• State of Speed Estimation for Areas with TDMs

• Conclusions

Starting Point1997 HPMS Average Speeds by Functional Class.

not accurate, obsolete

• HPMS Functional Class # Rural/Urban Description 1997 HPMS Average Speeds (mph) • 01 Rural Interstate 50.4• 02 Rural Principle Arterial 47.4• 06 Rural Minor Arterial 34.9• 07Not Rural Major Collector31.5• 08 Rural Minor Collector31.5• 09 Rural Local 31.5• 11 Urban Interstate 49.0• 12 Urban Freeway 50.5• 14 Urban Principle Arterial 28.0• 16 Urban Minor Arterial 20.6• 17 Urban Collector 21.1• 19 Urban Local 21.1

HPMSFunctionalClass #

Rural/Urban Description 1997 HPMSAverageSpeeds(mph)

01 Rural Interstate 50.402 Rural Principle

Arterial47.4

06 Rural Minor Arterial 34.907 Rural Major

Collector31.5

08 Rural MinorCollector

31.5

09 Rural Local 31.511 Urban Interstate 49.012 Urban Freeway 50.514 Urban Principle

Arterial28.0

16 Urban Minor Arterial 20.617 Urban Collector 21.119 Urban Local 21.1

Data Collection - Speeds

• Spot Counts

• Automatic Traffic Recorders (ATRs)

• Intelligent Transportation Systems (ITS)

Data Collection Spot Counts

Average Speed Data from Spot Counts

One county (Hardin County) chosen to assessfeasibility and accuracy

HPMSFunctionalClass #

AverageCollected Spot(Instantaneous)Speed (mph)

AverageSpeedLimit (mph)

# Samples

2 67.4 65 16 58.3 55 47 56.7 52.5 48 65.3 55 49 52.2 45 412 46.6 55 214 58.1 45 117 38.0 35 319 28.1 25 4

Data Collection ATRs

Average Speed Data from AutomaticTraffic Recorders

HPMSFunctionalClass #

AverageSurveyedInstantaneousSpeed (mph)

AverageSpeed Limit(mph)

1 64.7 65

2 59.0 55

6 41.9 55

7 51.2 55

11 64.6 55

12 56.3 55

14 41.5 55

17 42.2 35

Flexibility with data collectionVery few urban locations

Data Collection ITS

Free Flow Speed Estimation Using ITS Data, Louisville, KY.

Route DirectionAverage Free Flow Speed(mph)

I-64 East 60.7

I-64 West 59.8

I-65 North 62.0

I-65 South 57.0

I-71 North 65.5

I-71 South 65.0

High quality data, but limited to 2 cities and oneFunctional class

State of Speed Estimation for Areas without TDMs (Rural

Areas)

• Survey of literature

• Proposed national research

• Speed estimation workshop

• Highway Economic Requirements System (HERS)

Survey of Literature

• NCHRP Report 387

• TMIP Travel Model Speed Estimation

• Highway Capacity Manual

Proposed National Research

• Submitted 2 proposals to NCHRP 8-36

Speed Estimation Workshop

• Workshop conducted by Dr. Rich Margiotta of Cambridge Systematics

• Included Kentucky Model User’s Group

• Recommended HERS methodology

Travel Demand Models (TDMs)

(Urban Areas)• Status quo

• Brainstorming sessions/changes

Travel Demand Models (TDMs)(Urban Areas)-Recommendations

• Use of improved BPR equations

• Use of more accurate free flow speeds

• Calibrate models for speed in addition to volume

• Develop standard modeling procedures for statewide usage

Speed - Conclusions

• With MPOs and Consultant Partners, Develop Consistent Methodology for TDMs

• For Other Areas, Develop HERS Solution Based on Kentucky Data Availability

• Provide to Air Quality Agency TDM Speeds where available and Rich M. HPMS/HERS results for other areas

Final MOBILE6 Speed Estimations

Summary of Average Speeds for Nonattainment Areas.

HPMSFunctional

Class #

HERSAverageSpeeds(mph)

Owensboro ModelAverageSpeeds(mph)

AshlandModel

AverageSpeeds(mph)

MarshallCo.

ModelAverageSpeeds(mph)

Scott Co.Model

AverageSpeeds(mph)

FayetteCo.

ModelAverageSpeeds(mph)

OKIModel

AverageSpeeds(mph)

01 71.0 NA 64.9 64.4 61.6 NA 67.7

02 51.6 50.4 40.6 55.4 55.0 NA 45.1

06 42.3 40.2 36.9 54.1 54.2 NA 38.9

07 46.1 33.8 35.9 50.0 50.1 NA 37.5

08 NA 32.9 NA 37.6 54.5 NA 28.3

09 NA 15.1 10.0 35.0 38.6 NA 28.1

11 62.9 NA 55.0 NA NA 49.0 66.3

12 58.8 54.5 NA NA NA 50.5 56.5

14 38.9 31.2 31.8 NA 50.6 28.0 33.0

16 37.1 39.3 29.7 NA 41.5 20.6 32.5

17 37.0 30.7 29.5 NA 45.0 21.1 28.5

19 NA 14.1 10.0 NA 34.7 21.1 26.7

Review of Actions• Rich Margiotta MUG workshop (8/14/02)• TDM/speed workshop (12/6/02)• DVMT/speed data submitted to DAQ for new 8-

hour ozone standard (1/24/03)• Randy Simon used HERS and “local” data to

calculate speeds for AQ submission (5/03)• Highway Speed Estimation for M6 by Kentucky -

presented at AWMA (6/23/03)• Poster at TRB Partnering Conf. (5/16/03)• Speed study initiated with KTC (7/15/03)

Future Directions• Develop standard modeling

procedures for statewide usage

• Investigate other local traffic parameters such as VMT & Speed by time-of-day and vehicle type

• Explore the use of registration data/crash data

Conclusion• It is important to establish a consistent speed

methodology for the state.• It is equally important look at other

transportation related MOBILE6 inputs.• Thank you for your attention.• Questions/Comments?• Email:Jesse.mayes@mail.state.ky.us