Impact of DART Light Rail (Dallas) on
Traffic Congestion

Based upon Dallas Area Rapid Transit (DART) and Texas Transportation Institute data, it is estimated that the existing light rail lines are removing approximately 0.1 percent of traffic volume in the Dallas area (not Dallas-Fort Worth). This represents 2.3 percent of the 1995-7 average daily increase in vehicle miles (latest data available).

This means that DART's light rail lines have removed the equivalent of 8.3 days of traffic growth in the Dallas area. It is thus estimated that the traffic volume level that would have been reached on June 22, 1998 without light rail was postponed as a result of light rail to June 30, 1998 The capital cost per day's volume of traffic is an estimated $102 million.

Traffic Volume and Air Pollution Levels Reached on this Day without Light Rail June 22, 1998
Are Estimated to Have Been Reached Instead on this Day as a result of Light Rail June 30, 1998
Days of Traffic Growth that Nullify Light Rail's Traffic Reduction Impact: 8
Cost per Day $102,000,000

Calculations and methodology are shown below

Annual Light Rail Passenger Miles 58,916,771 1998 National Transit Database
Estimated Weekday Passenger Miles 196,389 Annual divided by 300
Auto Driver Diversion Rate 35.5% DART Survey: Assumes 0.5 Driver Car Pool Ratio
Light Rail Transfer from Drivers: Vehicle Miles 69,708 Weekday Passenger Miles times Auto Driver Diversion Rate
Annual Daily Increase in Roadway Vehicle Miles 3,000,000 Texas Transportation Institute: 1995-7 Annual Rate
Light Rail Related Reduction in Roadway Vehicle Miles Relative to Growth in Vehicle Miles 2.3% Light Rail Transfer Divided by Total Travel
Days of Traffic Volume Increase Transfered to Light Rail 8.3 Percentage Reduction times 365
Capital Cost per Day of Traffic Volume Reduction $102,000,000 Days of Traffic Volume Reduction Divided by Light Rail Capital Cost

The Public Purpose: One of National Journal's Top 4 Transport Internet Sites
The Public Purpose
Demographic Briefs
Government Cost Review
Gov't Employment Fact Book
Highway & Motorway Fact Book
Intercity Transport Fact Book
Labor Market Reporter
School Transport Fact Book
Transport Fact Book
Urban Policy
Urban Transport Fact Book
Competitive Tendering Website
Intl Comp. & Ownership Conference
Alternatives to Light Rail in Seattle

Contact by E-Mail
Subscribe (Free)
Corrections Policy & Rights

The Public Purpose     WENDELL COX CONSULTANCY     Demographia
P. O. Box 841 - Belleville, IL 62269 USA
Telephone: +1.618.632.8507 - Facsimile: +1.810.821.8134
To facilitate the ideal of government as the servant of the people by identifying and implementing
strategies to achieve public purposes at a cost that is no higher than necessary.

(c) 2002 --- Wendell Cox Consultancy --- Permission granted to use with attribution.