Skip to main content

First national study of US travel time reliability

Texas Transportation Institute (TTI) has published the 2011 Congested Corridors Report, the first nationwide effort to identify reliability problems at specific stretches of US highway responsible for significant traffic congestion at different times and different days. Researchers noted that the corridors included in the report were identified by the data itself.
April 30, 2012 Read time: 2 mins
RSS2347 Texas Transportation Institute (TTI) has published the 2011 Congested Corridors Report, the first nationwide effort to identify reliability problems at specific stretches of US highway responsible for significant traffic congestion at different times and different days. Researchers noted that the corridors included in the report were identified by the data itself.

5367 INRIX, a leading provider of traffic data and analytics, originated the corridor approach, using 10 hours of congestion per week to define a starting point for a congested corridor. To be considered a “corridor,” according to the Inrix standard adopted for this report, congestion should impact a freeway segment at least three miles long.

“Until now, we’ve been able to measure average congestion levels,” says TTI research engineer Bill Eisele, “but congestion isn’t an ‘average’ problem. Commuters and truckers are understandably frustrated when they can’t count on a predictable trip time from day to day.”

The report describes congestion problems in 328 seriously congested corridors over a variety of times — all day, morning and evening peaks, midday, and weekends. Not only were these roads found to have more stop-and-go traffic than others, they were also much less predictable — “so, not only does it take longer, commuters and truckers have a difficult time knowing how much longer it will take each time they make the same trip” said co-author David Schrank.

The 328 corridors, while accounting for only six per cent of the nation’s total freeway lane-miles in the US and 10 per cent of the traffic, account for 36 per cent of the country’s urban freeway congestion.

As the first look at travel time reliability across the US, researchers believe that the report can be useful in determining where transportation system improvements will have the greatest impact.

Click here for a copy of the report.

For more information on companies in this article

Related Content

  • Roadtec changes the game of asphalt paving
    December 20, 2016
    Truly innovative is Roadtec’s Shuttle Buggy material transfer vehicle. John Irvine, President of Roadtec, explains how and why the ‘Buggy’ changed the game of asphalt paving Road paving technology changed dramatically in the 1930s when the American inventor Harry Barber unveiled the very first asphalt paver. Barber was what we today would call a “game-changer”. Innovations like Barber’s don’t come around often. In fact, decades can pass until another breakthrough product pushes the productivity and q
  • Texas boosts infra investment
    September 16, 2024
    The investment includes the adoption of a 10-year US$104.2 billion transportation plan by the Texas Department of Transportation.
  • UK traffic jams cost drivers £426mn in wasted fuel, report claims
    December 10, 2012
    Traffic jams in the UK are costing the country's 8.2 million drivers US$683.31 million (£426mn) a year in wasted fuel, according to an estimate in a report by the analytics firm Inrix. The cost, which equates to £52 a vehicle, is on top of an estimated wasted driver time cost of £2.7bn. Out of the traffic on the country's roads during the day Inrix states that 19% is freight, with business vehicles passing on £1.1 billion of costs every year to consumers in order to cover the cost of them waiting in traffic
  • Navtech Radar to showcase ClearWay radar-based safety and monitoring systems
    March 19, 2012
    Navtech Radar will be showcasing the safety and economic benefits of using longer-range radar systems for Automated Incident Detection (AID) and enforcement at Intertraffic 2012. The company’s ClearWay sensor technology is currently deployed in live tunnel and above-ground environments in Northern Europe and has been further developed to provide count and classification capabilities as well as an effective counter to illegal tailgating and unsafe lane-change manoeuvres.