Estimating Volumes for I-95 HOT Lanes in Virginia Prepared for: 2009 Planning Applications Conference Houston, TX May 18, 2009 Prepared by: Kenneth D. Kaltenbach, P.E. The Corradino Group, Inc Jeremy Raw, P.E. Virginia Department of Transportation Transportation & Mobility Planning Division May 18, 2009
23
Embed
Estimating Volumes for I-95 HOT Lanes in Virginia Prepared for: 2009 Planning Applications Conference Houston, TX May 18, 2009 Prepared by: Kenneth D.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Kenneth D. Kaltenbach, P.E.The Corradino Group, Inc
Jeremy Raw, P.E.Virginia Department of Transportation
Transportation & Mobility Planning Division
May 18, 2009
Summary
What are HOT lanes? I-95 HOT Lanes in
Fredericksburg How do you model HOT lanes? Structure of the finished model Model performance
What are HOT lanes?
High-Occupancy Toll (HOT) lanes are a class of managed lanes.
Designated lanes, usually on a freeway Separated from general purpose lanes Toll charged for low-occupancy vehicles No toll for high-occupancy vehicles Electronic toll collection
… Sell the excess HOV capacity
What are the benefits?
I-95 is over capacity, widening for more general purpose is not likely
Encourage three-occupant autos Sell excess capacity in HOV lanes Create a new revenue stream by
charging those willing to pay for premium service – 50 mph guaranteed
HOT Lanes Modeling in Fredericksburg
HOT Lanes already operating in Northern Virginia (Washington DC area)
HOT Lane extension to Fredericksburg is a new project
Fredericksburg Area MPO (FAMPO) needed to include the project in LRP and Air Quality Conformity.
Had to be implemented quickly, about 90 days.
Extent of the Virginia I-95HOT Lanes Project
Model Effort
Fredericksburg Only Daily 24 hours
No mode choice
No Transit
Daily assignment
Extend net into DC Estimate AM, PM
and off-peak periods Discrete auto
occupancy levels Virginia Railway
Express Period assignment
with toll and HOT lane allocation
“VERSION 2.0 MODEL”
“VERSION 3.0 MODEL”
Model Requirements
Important Factors for HOT Lane ModelPoint of entrance/exitVariable tolling to control lane congestionHOT lane effects outside model area held
constant Include Virginia Rail Express ridership
effects (DC-oriented commuter rail)
Current FAMPO Version 2.0 Model Network
Northern External is Prince William Co. Line
Updated Network
I-95 External Station split into distance stations
External skims (HOT vs. Free) computed from NCRTPB model
Use of I-95 outside model area held constant
Northern External is Potomac River
Modeling Assumptions/Sources Distribution of trips on I-95 corridor outside
Fredericksburg area borrowed from National Capital Region model (DC)Compiled via select link analysis
Auto occupancy rates disaggregated from FAMPO model
Time of Day directional traffic from VDOT traffic counts
Toll/free split borrowed from I-394 MnPASS Express Lane Stated Preference Survey
Modeling Assumptions
Length of trip outside area influences HOT lane use within area
Vehicle occupancy alters sensitivity to tollSOV, HOV-2, HOV-3
HOT versus free lane choice made in assignment
Model AM, PM and Off-Peak periods separately Value of time based on NCRTPB model, but
adjusted to 2008 values ($10.24 - $17.06 / hr)
Operating Assumptions
Goal: at least 50 mph in HOT lanes
3+ person carpools and buses: No Toll
2-person carpools and drive alone: Pay Toll
Directional operating plan for HOT lanes to conform with DC peak directions (AM-NB, PM-SB, Off-split)
Transponders -- no toll collection delay
Toll Diversion
TOLL DIVERSION CURVE
Toll($)/time saved (min) Fraction Toll
0 1.000
2 0.900
5 0.400
10 0.280
20 0.100
30 0.050
40 0.020
50 0.018
60 0.015
70 0.013
80 0.010
Toll Choice (from MnPass)
0.000
0.200
0.400
0.600
0.800
1.000
1.200
0 20 40 60 80 100
Toll $/minute saved
Frac
tion
Toll
Source: I-394 MnPASS Express Lane Stated Preference Survey
Toll Calculation
Function of the V/C on the managed lanes
Logit function Several toll
ranges explored Final toll rate
ranged between $.00 and $0.25 per mile
Toll Function
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2
Volume/Capacity
Toll $
per M
ile
Commuter RailVirginia Railway Express
VRE post-processing model Evaluates impact of HOT lanes on
VRE Incremental logit model AM peak period trips only Cube Voyager PT network
Model Performance and Sensitivity
Validation Sensitivity Toll Estimation HOT lane volumes
Validation
Volume Group Volume Range RMSE Number of Observations
1 1- 5,000 56.0% 480
2 5,000- 10,000 29.1% 128
3 10,000- 20,000 18.7% 102
4 20,000- 30,000 31.0% 30
5 30,000- 40,000 18.3% 36
6 40,000- 50,000 20.6% 6
7 50,000- 60,000 9.9% 18
8 60,000- 70,000 20.3% 4
10 80,000- 90,000 18.0% 2
Total 1-500,000 34.7% 806
Usual 4-step methods – for example …
Model Sensitivity
AM NORTHBOUND DIRECTION TRIPS LOADING AT FREDERICKSBURG, LEELAND RD., AND BROOKE STATIONS
AM NORTHBOUND
I-95 VEHICLES* YEAR ALTERNATIVE VRE BOARDINGS GP HOT TOTAL