TxDOT revised its Texas’ 100 most congested roadway segments, and a new list reveals that the greater Houston area has five of the top 10 and the Dallas area has three.

The list was compiled using traffic speed data to calculate delay instead of estimations based on traffic volume. It pinpoints the traffic hotspots in the state with the goal of assisting transportation planners in prioritizing roadway and transit projects.

Texas A&M University’s Texas Transportation Institute worked with TxDOT to develop the list and improve methodology. TTI worked with INRIX of Kirkland, Wash, a private firm that collects information for GPS units and smart-phone applications, to assess total delays by actual speed data and traffic volume.