Transportation leadership you can trust.

presented to

TRB 11th Conference on Transportation Planning Applications

presented by

Dan Goldfarb, P.E.Cambridge Systematics, Inc.

May 2007

A Practical Approach for Post-Processing Managed Lane Facilities

2

ETL Lanes

Electronic Toll Lanes

Tool for Managing Demand

Price to Keep Traffic Moving

Guide for HOT Lane Development, FHWA,

3

ETL Projects

Maryland State Highway Administration Projects

• Inter-County Connector (ICC)

• Capital Beltway (I-495/I-95)

• I-270 from I-70 to I-370

• Western Mobility I-495 to I-270

Role - Developed Travel Demand Forecast

4

ETL Forecast Issues

Develop Year 2030 Forecast for the ICC

Toll Facility

Variable Tolls to Manage Demand

Guarantee Traffic Flow Reasonable LOS

Threshold LOS “C” to LOS “D” conditions –

1800 pcphpl

6% HV, Rolling Terrain – 1650 vph

Open Process for EIS

5

Travel Demand Model

MWCOG V2.1C Travel Demand Forecast Model

Validated Study Corridor

Base year 2000

No-Build Year 2030

Tolls ― Travel Time Penalty Assignment

6

V2.1C Toll Application Improvements

Convert Toll Cost to Time Equivalent

Trip Distribution

4 Income Groups

Work & Non-Work Purposes

Mode Choice

Average Cost by Purpose

Vary Peak & Off-Peak

Per Person Cost for HOV

Assignment

Vehicle Cost

Vary Peak & Off-Peak

Source: MWCOG V2.1C User’s Guide & Technical Memorandum Oct-21-2003

7

Time & Cost Equivalents

0

5

10

15

20

25

30

35

INC 1 INC 2 INC 3 INC 4

minu

tes p

er $

Wage (min/$) Work Eqv (min/$) Non-Work Eqv (min/$)

By Income Level & Purpose

Source: MWCOG User’s Guide V2.1D #50 Model

8

Time & Cost Equivalents

0

5

10

15

20

Airport Auto SOV Auto HOV Auto Truck

min

utes

per

dol

lar

Peak (min/$) Off-Peak (min/$)

By Vehicle & Time Period

Source: MWCOG User’s Guide V2.1D #50 Model

9

Toll Cost & Time

Vehicle

Peak Off-Peak

(minutes) (minutes)

Airport Auto 4.54 3.40

Single Occupant Auto 9.25 9.93

Multi Occupant Auto 11.61 11.56

Truck 23.22 24.90

3.45 miles

5.62 miles

IncomeGroup

Peak Off-Peak

WorkNonWork Work

NonWork

(minutes) (minutes) (minutes) (minutes)

inc 1 38.28 54.78 28.71 41.09

inc 2 14.15 20.14 10.61 15.10

inc 3 8.34 11.97 6.26 8.98

inc 4 4.17 5.99 3.13 4.49

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Travel Demand Forecast Model Assignment

Large Geographic Area

Coarse Network

Macro-level Assignment

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Refinement of The Travel Demand Model Output

Post-Process

Applied at the link level

Procedures from NCHRP-255

“Link Smoothing”

Benefits• Raw Assignment Capital Beltway RMSE 14%

• Link Refinement Capital Beltway RMSE 6%

• Annual Growth Factor RMSE 25%

12

Link Refinement

Part 1 – Model Bias

• Ratio Adjustment

• Difference Adjustment

Part 2 – Redistribution

• Count factor

• Capacity Factor

13

ETL — Managed Facility

Redistribution Problem

Capacity Based

Constraints:→ Reflect Managed Nature of Facility

→ Reflect the Results of Model Run

14

Post-Processing Approaches for ETL Facility

Use the Raw Model Output

Limit ETL Facility to 1650 vphpl

Incorporate ETL Into the Link Refinement Procedure

15

ETL Raw Model Output Approach

Represent the Toll Impact on the Demand

Issue of Coarse Network – Loading Points

Macro ― Level Assignment Algorithm

Facility Open to All Traffic ― Over/Under

16

Fixed Volume Flow Approach

Limit the Volume 1650 vphpl

Redistribute the Surplus or Shortfall to other Parallel Competing Routes

Differs from Results of the Travel Demand Model Assignment

Not Reflecting the Cost of Toll – Pricing Question

17

Incorporating the ETL into the Link Refinement Approach

Redistribute Volumes Over the Cutline

Capacity & Count Factors

New Facility Impedance – Capacity

Adjust Capacity for the ETL Facility Reflect Demand

18

Capacity Adjustment

Freeway LOS “E” Capacity (2310 vphpl)

Apply Peak to Daily Ratio Factor (8%) ― Daily Capacity

Two Model Runs

• Toll

• Non-Toll

Adjust the ETL Capacity Based on the Ratio of the Raw Assignments for Toll & Non-Toll

Apply the Ratio to the LOS “E” Capacity for the ETL

Redistribute Volumes over the Cutline

Review Results – Adjust Toll Accordingly

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Overview of Process

EndNo Yes

Start

SetToll Cost

ExportLink Data

Assign Links

to Cutlines

CalculateETL LaneCapacity

EvaluateToll

Demand

Demand OK

RunTDFMNo Toll

RunTDFM

Toll

Volnon-toll

Voltoll

× Capacity LOS E{

PeakOff-Peak

NCHRP-255 Procedures

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Results

Facility 2000 CountDirect Model Output Raw

Fixed Capacity

Incorporate Part 2 of Link

Refinement Procedure

MD 28 20,000 vpd

Randolph Road 33,800 vpd

ICC

21

Results

Facility 2000 CountDirect Model Output Raw

Fixed Capacity

Incorporate Part 2 of Link

Refinement Procedure

MD 28 20,000 vpd

Randolph Road 33,800 vpd

ICC 68,986 vpd

22

Results

Facility 2000 CountDirect Model Output Raw

Fixed Capacity

Incorporate Part 2 of Link

Refinement Procedure

MD 28 20,000 vpd 35,927 vpd

Randolph Road 33,800 vpd 34,803 vpd

ICC 68,986 vpd

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Results

Facility 2000 CountDirect Model Output Raw

Fixed Capacity

Incorporate Part 2 of Link

Refinement Procedure

MD 28 20,000 vpd 35,927 vpd

Randolph Road 33,800 vpd 34,803 vpd

ICC 68,986 vpd 78,546 vpd

24

Results

Facility 2000 CountDirect Model Output Raw

Fixed Capacity

Incorporate Part 2 of Link

Refinement Procedure

MD 28 20,000 vpd 35,927 vpd 26,667 vpd

Randolph Road 33,800 vpd 34,803 vpd 42,501 vpd

ICC 68,986 vpd 78,546 vpd

25

Results

Facility 2000 CountDirect Model Output Raw

Fixed Capacity

Incorporate Part 2 of Link

Refinement Procedure

MD 28 20,000 vpd 35,927 vpd 26,667 vpd

Randolph Road 33,800 vpd 34,803 vpd 42,501 vpd

ICC 68,986 vpd 78,546 vpd 62,958 vpd

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Results

Facility 2000 CountDirect Model Output Raw

Fixed Capacity

Incorporate Part 2 of Link

Refinement Procedure

MD 28 20,000 vpd 35,927 vpd 26,667 vpd 29,391 vpd

Randolph Road 33,800 vpd 34,803 vpd 42,501 vpd 46,667 vpd

ICC 68,986 vpd 78,546 vpd 62,958 vpd

ICC Toll Volume: 68,986 vpd

ICC No-Toll Volume: 127,723 vpd

Capacity Reduction Factor: 52%

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Toll Demand Analysis

ICC Corridor 1 ADT Volumes

-

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

90,000

100,000

110,000

120,000

130,000

140,000

150,000

160,000

170,000

West of I-370 West of MD 97 West of MD182

West of MD650

West of US 29 West of BriggsChaney

West of A-59 West of I-95 West of VirginiaManor

West of US 1

AD

T

Toll 8/5 Toll 30/20 No Toll Toll 20/15 Toll 15/10

Managed LOC "C" Capacity

28

Summary

Developing ETL Forecast

Traditional 4-Step Travel Demand Forecast Model

Incorporate ETL Characteristics into NCHRP-255 Link Refinement Procedures

Redistribute the Link Volumes based on Capacity

Calculate the ETL Capacity Based on No-Toll and Toll Model Runs & Adjust ETL Capacity for Redistribution

Open Process for EIS Requirements

Report Regional Impacts & Measures of Effectiveness