Measuring the Distribution and Costs of Congestion Tim Lomax Texas Transportation Institute http://mobility.tamu.edu
The Congestion Measurement Story Travel time, variations, compare to goals WHAT? WHY? WHERE? Is it a problem? Causes? Areawide, Sub-Region, Corridor, Facility, Service WHEN? HOW? Day, Week, Season, Events Fix it? Define Success?
Performance Measure Needs Start with Goals and Vision Congestion and Reliability Location, Time & Costs Effect of Solutions and Trends Connect to Expectations Connect to Individual Actions Travelers Businesses Agencies
What? Urban Mobility Measures Delay/Person Hours per year Travel Time Index Buffer Time Index Peak Period Travel Time Free Flow Travel Time 95th % Travel Time Average Travel Time Average Travel Time
Travel Time Index Travel Time Index 1.50 1.40 1.30 1.20 1.10 1.00 1982 2000 Small Medium Large Population Group Very Large
Annual Delay per Person Hours 100 80 60 40 20 0 1982 2000 Small Medium Large Population Group Very Large
Growth of Congested Travel 1982 to 2000 1982 2000 Severe 8% Extreme 5% Extreme 19% Uncongested 34% Heavy 8% Uncongested 69% Moderate 10% Severe 20% Heavy 14% Moderate 13%
Where? Congestion and Population Travel Time Index 2.00 1.80 1.60 1.40 1.20 1.00 Congestion levels in each of the 75 urban areas studied. Small Medium Large Very Large Population
12:00 A M 2:00 A M 4:00 A M 6:00 AM 8 :00 AM 1 0:00 A M 12:00 PM 2:00 P M 4 :00 PM 6:00 P M 8:00 P M 10:00 PM 12 :00 A M When? Average and Trip Planning Time Index Value 3.50 3.00 2.50 2.00 1.50 Average Travel Time Trip Planning Time (19 of 20 trips) 1.00 Mid 6A Noon 6P Mid
When? Peak Period Congestion Levels Percent of Days in 2001 25% 20% 15% 10% 5% Average Travel Time Index Median Time Penalty = 27% 10% of Days 0% 1.00 1.20 1.40 1.60 1.80 2.00 Travel Time Index
When? Peak Period Frustration Levels Percent of Days in 2001 25% 20% 15% 10% 5% 0% Average 19 of 20 Trips TTI Median = 27% Penalty Median = 60% Penalty 1.00 1.20 1.40 1.60 1.80 2.00 Travel Time Index
Congestion and Reliability Are Related 50% Buffer Time Index 40% 30% 20% 10% 0% 1.00 1.10 1.20 1.30 1.40 1.50 Travel Time Index
Congestion Costs Delay and fuel - $68 Billion (2000 $) Extra travel time - 3.6 Billion Hrs Extra fuel consumed 5.7 Billion Glns Business productivity Air quality Worker, market & supplier accessibility
Congestion Successes How are They Measured? Lower travel time More options Cheaper travel Predictable travel times Shorter trips Less congested time and space
Toolbox: No Lack of Solutions Alternate Hours of Travel Variable Pricing Strategies Flow Signals Traffic Signal Improvements Incident Management Event Management Local Bus Service Neighborhood Circulator Bus Activity Center Circulator Bus Express and Park & Ride Service Demand-Response & Hybrid Bus Service Vanpools Telecommuting Urban Development Patterns Parking Strategies Bicycle and Pedestrian Light Rail Bus Rapid Transit Commuter / Light Rail Managed Lanes/Truck Lanes Electronic Toll Collection Systems Intersection Improvements One-Way Streets Changeable Lane Assignments Arterial Access Management Technology-Based Transit Improvements Ridesharing Telecommuting Assessing the Transportation Impacts Parking Strategies Bicycle and Pedestrian Elements Fare Strategies Street Continuity New Lanes New Toll Roads Grade Separation Geometric Design HOV Lanes Multimodal Corridors Freight Rail Improvements Why not more Success?
Many Reactions to Congestion Acceptance Frustration Plan more time Vote to fix the problem or to blame Move job, business or home Is this flexibility cost free?
Variety of Solution Types 100% % Varies for Each City Diversify Development Patterns Manage the Construction Process Manage the Demand Increase System Efficiency Build More Capacity 0%
Strategy Mix Will Be Different Outer Loop Capacity Efficiency Demand Capacity Efficiency Demand Capacity Efficiency Demand Inner Loop Add Capacity Greater Efficiency Demand Management
Adding Roads Helps Congestion Increase (%) 250 200 150 100 50 3.5 3.0 2.5 2.0 1.5 29 Areas Demand 10% to 30% faster 40 Areas Demand 30% faster 6 Areas Demand = Roads 0 1.0 1980 1985 1990 1995 2000 Year
... But, Difficult to Add Enough Roadway. Lane Miles 150 120 90 60 30 0 Lane-Miles Needed Lane-Miles Added Small Medium Large Very Population Group Large
Transit Is Not The Only Solution, Either 1,050 Yearly New Needed (000) 250 200 150 100 50 Current Riders Trips Needed 0 Small Medium Large Population Group Very Large
Solutions? In the past we managed: Construction Projects Supply & Capacity Operations Demand
Solutions? Need for Expanded Management In the past we managed: Construction Projects Supply & Capacity Operations Demand Should we add? Pricing? Expectations? Consensus and Effort = Success
Summary Congestion is growing Solutions are multimodal policies, programs and projects More aggressive operation and deployment Achievable goals Stop the growth of congestion Improve reliability Provide more travel options
what I found in practice was that the tool that made the most difference in my community was transportation. Nothing else had as great an impact on our economic development, on the pattern of growth, or on the quality of life." -Norman Y. Mineta, former Mayor San Jose, CA Current Secretary of Transportation