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NATHAN P. BELZ, M.S., E.I. University of Vermont Transportation Research CenterBurlington, VT 05405-1757Email: [email protected]
LISA AULTMAN-HALL, Ph.D.Email: [email protected]
JIM SULLIVAN, M.S., P.E.Email: [email protected]
TRANSIT NETWORK EFFICIENCY AND TRANSIT-SUPPORTIVE ZONES
Using Technology to Improve Transportation Operations 04.26.2012
TRANSPORTATIONRESEARCH CENTER
MOBILITY. SUSTAINABILITY. LIVABILITY.1
WHAT ARE THE CHALLENGES OF TRANSIT IN RURAL STATES?
(Spatial Constraints: Long Travel Distances & Low Densities)
DISAGGREGATEOBJECTIVEPROCESSSTATEWIDE
3
WHAT ARE THE SHORTFALLS OF PAST SPATIAL RESEARCH?
(Zonal level analysis based on urban focus, assumptions of homogeneity within zones)
4
Single Family PointMulti-Family PointNon-Residential Point
5
Single Family PointMulti-Family PointNon-Residential Point
Single Family PointMulti-Family PointNon-Residential Point
Demand Potential (DP)
Single Family PointMulti-Family PointNon-Residential Point
=
=
Equivalent DP
1 2 3
4 5
Criteria to be a Transit-Supportive Zone1. Centroid must be a local density maximum2. Σ EDP must be greater than or equal to transit viability threshold3. Assumes transit riders are willing to walk one-half mile
Burlington, VT & Surrounding
Montpelier, VT
A
A
B
B
6
1% of land
43% of trips(86% intercity)
21% of VMT
Evaluation of Existing Statewide Rural Transit Network
Use Demand Potential and Existing Fixed-Route Transit to:1. Generate Energy-Efficient Transit Network2. Generate Equitable Transit Networks
• Connectivity “Fairness”• Access to Critical Destinations
4. Compare using Network-Overlap Ratio
7
One of the lowest average population densities in the United States
Served by 11 different transit agencies
Coverage ranges from 8 to 122 miles (average is 74); 1,300 miles total
Reaches 77% of Vermonters
Fixed-Route Transit in Vermont
8
Using Transit-Supportive Zones as origins and destinations
Trip distribution used a Gravity Model
Assignment of Person-Trips on the Road Network
Remove routes with fewer than 11.2 persons per hour
Energy-Efficient Network
9
153 miles less than the existing merged network
Reaches 13 fewer towns than the existing network
Accessible to 75% of Vermonters
Energy-Efficient Network
10
Connectivity “Fairness”
70 miles more than the existing merged network
Reaches 6 more towns than the existing network
Accessible to 79% of Vermonters
Equitable Networks
11
Equitable Networks“Access to Critical Locations”
Ensure access to critical locations for ALL Vermonters
• Seniors with restricted driving• Non-driving adults• School-age children• ¼ mile access distance
Critical locations in the context of equity
• Health care / hospital• Grocery
12
Network-Overlap Ratio
Formulation N-O Ratio = Ln,m / Lm
networks coincide perfectly
networks do not share any links in common.
0 1
Evaluate existing merged and idealized networks of fixed-route transit in Vermont
13
Transit Network Total Miles of Network
% Vermont Towns Reached
(of 255)
% Population Reached
(of 609,000 in 2000)
Population Reached Per Mile
of NetworkN-O
Existing 1,318 44 77 358 --
Energy-Efficient 1,153 39 75 395 0.58
Connectivity-Fairness 1,388 46 79 349 0.58
Access to Critical Locations 2,039 63 90 269 0.64
AGENCY Setting Service Area Type
Network Overlap (EE to Existing)
Network Overlap (ACL to Existing)
Advance Transit (AT) Rural Town 0.09 0.14
Connecticut River Transit (CRT) Rural Valley Region 0.56 0.63
Deerfield Valley Transit Association (DVTA) Rural Valley Region 0.03 0.24
Rural Community Transportation (RCT) Rural Towns (2) 0.27 0.40
Stagecoach Transportation Services (STSI) Rural Valley Region 0.051 0.451
Chittenden County Transportation Authority (CCTA) Urban County 0.84 0.84
Green Mountain Community Network (GMCN) Urban Town 0.31 0.31
Green Mountain Transit Agency (GMTA) Urban Mountain Region 0.57 0.57
Marble Valley Regional Transit District (MVRTD) Urban Valley Region 0.75 0.75
Addison County Transit Resources (ACTR) Urban County 0.71 0.71
Town of Brattleboro Bus Line Urban Town 0.73 0.73
ENTIRE NETWORKS 0.58 0.64
Model transit networks• Spatially-optimal• Equitable-fairness• Equitable-access
CambridgeCambridge
Poultney
Hinesburg
Northfield
Johnson
Putney
Rockingham
Able to identify• Over-served areas• Under-served areas• Shortest-path discrepancies
15
Importance of disaggregate data• Generally much more available for urban areas• Illustrates application of E911 • Identifies need for similar data on national scale• Application as data-driven decision tool
TSZs and Potential Transit Demand• Relatively large proportion of substitutable intercity trips• Not just in the one Vermont MPO
Evaluation of Existing System• Relatively efficient, especially in urban areas• Over and under serviced areas should be assessed• Better metrics for equity and access are needed
16