Forecasting Traffic for a StartUp Toll Road

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Forecasting Traffic for a Start-Up Toll Road
12th TRB National Transportation Planning
Application Conference May 18, 2009
David Schellinger, P.E. Vice President Modeling
/ Toll Feasibility Systra Mobility
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Presentation Overview

• Challenges to Forecasting Traffic
• The Corridor
• The Project Growth Trends / Unique Conditions
• Modeling Methodology
• Role of Regional Model
• Customized Toll Diversion Process
• Results
• Early Trends / Issues
• Areas for Improvements

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Project corridor

• Central Texas Turnpike System
• Northwest Elements
• SH 45 North
• Loop 1
• SH 130
• System Length 65 Miles
• SH 130 49 Miles
• Northwest Elements 16 Miles

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Segment 1 IH 35 US 79

• SH 130 ELEMENT
• Closed System
• 4 Segments
• 4 Mainline Plazas
• 15 Ramp Plazas

Opened Early 11/2006
Segment 2 US 79 US 290
Opened Early 12/2006
Segment 3 US 290 SH 71
Opened On Time 9/2007
Segment 4 SH 71 US 183
Opened Late 5/2008
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FORECASTING challenges

• Extremely High Growth Region
• Limited North-South Limited Access Facilities
• High Percentage of Truck Traffic
• First Toll Road Project in Region
• Unknown Values of Time
• Toll Bias and Emerging Payment Methods
• Greenfield Project
• Largely Undeveloped Corridor
• Background Network Improvements

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Modeling Approach

• Adopt Regional Model With Enhancements
• Additional Detail / Zonal Disaggregation
• Retain Existing Procedures
• Trip Generation
• Trip Distribution
• Mode Choice
• Utilize Advanced Highway Assignment Process
• Reflect Travel Conditions by Time of Day Market
  Segment
• Provide Robust Toll Diversion Process

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CAMPO REGIONAL MODEL (2000)
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FoRECASTING APPROACH

• Utilizes Approved MPO Model
• Facilitates Agency Approval
• Consistent Platform for Multiple Projects
• Sensitive to Availability of Competing
  Services/Policies
• Transit Options
• Land Use Policies
• Facilitates the Analysis of Projects Advancing
  Through Feasibility Levels

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FoRECAST sets DEVELOPED FOR PROJECT

• 2002 Investment Grade Study
• Basis of Project Financing
• Available Data Late 1990s
• Significant Growth Distributed West of I-35
• 2005 Investment Grade Study
• Remarketing Portion of Debt
• Available Data Early Census Results
• More Growth Distributed East of I-35

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Past Practice / Emerging Needs
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Emerging Toll Policy requirements

• Complex Tolling Policies
• Variation by Payment Type
• Variation by Frequency
• Variation by Agency / Operator
• Use Restrictions
• Restrictions by Payment Method
• Restrictions by Vehicle Type
• Variation in Pricing
• Time of Day Pricing (Peak/Off-Peak/Weekend)
• Congestion Pricing

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Potential Tolling Policies

• Variation by Payment Type
• Cash
• Transponder
• Video Tolling
• Variation by Frequency
• Commuter / Frequent Use Discount Plans
• Restricted by Payment Method
• Variation by Agency / Operator
• Multiple Agencies / Payment Policies

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Toll Facility Use Restrictions

• Restrictions by Payment Method
• ETC Only
• Transponder Only
• Transponder Video Billing
• Restrictions by Vehicle Type
• Auto Use
• General Use
• HOT Lane
• Truck Use
• Exclusive Truck Toll Roads

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Variation in Pricing

• Time-of-Day Pricing
• Peak/Off-Peak Rates
• Linked to Transponder Usage
• Weekend Surcharges / Discounts
• Congestion Pricing
• Pricing Based on Facility Usage
• Pricing Based on Conditions of Competing
  Non-Tolled Roadways

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Other issues influencing diversion

• Diversion Sensitive to Traveler Characteristics
• Income
• Trip Purpose
• Traveler Biases
• Dislike Toll Roads
• Favor Electronic Toll Collection
• Market Segmentation
• Travelers Acceptance of New Tolling Mechanisms

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Potential diversion forecasting techniques

• Toll Choice within Mode Choice
• Production-Attraction Methods provide mechanism
  to relate traveler characteristics such as income
• Responsive to policies that will alter mode usage
  (SOV vs. HOV)
• Toll Choice within Assignment
• Capable of addressing wide range of toll
  conditions
• Internally consistent results
• Capable of forecasting dynamic pricing options

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Technical Issues
NEEDS
TOOLS
LIMITATIONS
PROCESS
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Choice based procedures

• Choice Options
• Toll Choice as Part of Mode Choice Model
• Toll Choice via a Route Choice Model
• Desired Feature
• Simultaneous Choice and Assignment ensures
  consistency of results

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External Routine Consistency ISSUE

• Under Either Method Feedback is Required
• Consistency not Assured
• Convergence Difficult under Certain Conditions

Mode Choice
Mode Choice
Highway Assignment
Route Choice
Highway Assignment
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Path Consistency issues
Preload or Favored Path Implies 2.00
1.00
0.50
0.50
Toll Road
Choice Skim is 1.00
B
A
Toll Trips May be Assigned to Non-toll Paths
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POTENTIAL SOLUTION ??
SEQUENTIAL PROCESS
EMBEDDED ROUTE CHOICE MODEL
Route Choice
HIGHWAY ASSIGNMENT ROUTINE
ROUTE CHOICE SUBMODEL PURPOSE/VEHICLE TYPE
/PAYMENT TYPE
Highway Assignment
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Embedded Route Choice Model

• Assumes Toll Options Will not Impact the
  Selection of Travel Modes.
• Allows for the Development of Choice Functions
  and Parameters Specific to Auto Modes.
• Allows for Treatment by Market Segments, Similar
  to Mode Choice

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Toll diversion MODELING USING CUBE Voyager
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Benefits of Voyager for modeling diversion

• Voyager Highway Assignment Capabilities
• Choice-Based Procedures Embedded within
  Assignment Process
• Complex Modeling of Costs by Payment Type
• Extensive Segmentation Possible
• Integrate Traveler Characteristics (such as
  Income Levels)
• Dynamic Toll Estimation

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Advanced Toll Diversion Modeling

• Enhanced Highway Assignment Process
• Multiple Time-of-Day assignments
• Permits varying toll rates / usage options
• Enhanced estimation of traffic delays
• Customized toll diversion procedure
• Embedded Route Choice Submodels sensitive to
  payment methods and traveler characteristics.
• Trip purposes have individual Values of Time
• Permits separate treatment for cash and ETC
  Patrons
• Permits separate treatment by vehicle type
  (SOV,HOV, Truck)
• Dynamic Pricing Analysis
• Voyager or Voyager/CUBE Avenue Options

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Traveler Characteristics

• Diversion for Some Purposes is a function of
  Income
• Requires knowledge of home zone income
• Solution
• Partition Purpose into Production?Attraction
  Attraction?Production Movements
• Utilize Production Zone to Reference Zonal
  Income Values.

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Toll Diversion Model Structure
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Toll Diversion model parameters
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Toll Shares Hbw Purpose(2.00 Toll)
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Toll Share vs. Time Savings
Minimal time paths biased towards NonToll
Choice
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Toll Share vs. Cost
Minimal cost paths biased towards Toll Choice
(assumed reliability)
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Choice functions by time/cost conditions
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Initial results

• Comparison to 2005 Update Forecasts
• Observed Results for 2008
• Observed Traffic Reflect Economic Conditions
• Areas for Improvement

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SH 130 ESTIMATED AND OBSERVED TRANSACTIONs
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TRANSACTION COMPARISON BY SEGMENT
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PERCENTAGE OF TRANSACTIONS FOR MAINLINE PLAZAS
(AM PEAK)
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PERCENTAGE OF TRANSACTIONS FOR RAMP PLAZAS (AM
PEAK)
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PERCENTAGE OF TRANSACTIONS FOR MAINLINE PLAZAS
(PM PEAK)
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PERCENTAGE OF TRANSACTIONS FOR RAMP PLAZAS(PM
PEAK)
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AVERAGE AXLES PER TRUCK BY MAINLINE PLAZA
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TRUCK PERCENTAGE BY MAINLINE PLAZA
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QUESTIONS?