Commentary

Austin, Texas Tollroad Cuts Congestion and Pollution

Central Texas opened its first modern tollway on March 7, 2007, when the Central Texas Regional Mobility Authority unveigled the 183A tollway. Since then, the tollway has logged traffic of 55,000 transactions per day, more than double the number projected in the original forecasts. Notably, the tollway is also the first Texas tollway to go completely electronic, collecting tolls from an electronic tag and eliminating tollbooths altogether. Now, travelers using 183A cut 15 minutes off their trip travel time, a savings of 75 percent compared to using the conventional parallel road US 183 (see more on this below).

More importantly, perhaps, the CTRMA has made serious efforts to chronicle and evaluate the tollroad’s progress since the project began construction in 2005. They realized their success would be crucial for future projects and embarked on a program of due diligence and evaluation.

A December 2008 traffic study conducted by HNTB consultants found that travel speeds had increased, travel times fallen along the corridor, not just for the travelers using the tollway. According to the traffic report:

    • Overall traffic activity on 183A has increased 11.8% in the past 14 months.
    • Comparatively, overall traffic activity on the roadway network in the study area [corridor] has increased by 0.6% in the past 14 months.
    • In the past 14 months, traffic volumes on the 183A frontage roads north of CR 272 have decreased by 10.8%
    • Travel on [the parallel] US 183 decreased by 6.6% overall in the past 14 months attributable to increasing traffic diversion to 183A, a slowing economy, and high gas prices. Since 183A opened, travel on US 183 has decreased by as much as 36.8% on some segments, and by 17.4% overall.

Not only has traffic improved, but the tollway is contributing meaningfully to an improvement in air quality and reduction in pollution along the corridor as a result of the lower levels of congestion and higher travel speeds (and less time on the road). According to an environmental impact analysis performed by the mobility authority:

Based on data obtained from the vehicle emissions study, current traffic counts and previous time travel analysis, the following observations are noted and conclusions can be made for motorists traveling the 183A Toll Road as compared to traveling on US 183:

  • Average travel time was reduced by approximately 6-7 minutes;
  • Compared to US 183 prior to construction of 183A Toll Road, average time travel was reduced by approximately 15 minutes; a time reduction of over 75%;
  • All emissions were reduced for both peak and off-peak hours;
  • Fuel consumption was reduced for both peak and off-peak hours;
  • Estimated annual fuel savings per vehicle of 108 gallons with an annual cost savings of $281;
  • Total estimated annual fuel savings of 664,723 gallons with cost savings of $1,728,280;
  • Data indicates that for every vehicle that uses the 183A Toll Road, there is significant reduction in overall emissions within the study area when compared to all vehicles using US 183 only;
  • Annual reduction in emissions and fuel consumption was calculated to be:
    • Carbon Dioxide (CO2) emissions reduced by 28% (7,231.9 Tons/Yr)
    • Carbon Monoxide (CO) emissions reduced by 47% (21.8 Tons/Yr)
    • Nitrogen Oxides (NOx) reduced by 56%
    • Total Hydrocarbon (THC) emissions reduced by 37%
    • Fuel consumption reduced by 26%

The project’s success has allowed the CTRMA to advance plans to build an extension of this road and make other improvements along the corridor.