If you haven’t already seen it, we recommend checking out an important new source of real-world traffic congestion data provided by the company INRIX. Bryan Mistele, the president of INRIX, is a member of our National Transportation Policy Project, and his company is the leading provider of real-time, historical, and predictive traffic information. INRIX’s data collection is unique in that it combines Department of Transportation road sensor information with GPS and toll tag data from commercial vehicle fleets like taxis and trucks. In addition, the company can incorporate factors like weather, construction, school schedules, and sports events into its traffic predictions.
This type of hard data seems imminently more valuable than the modeling that has traditionally tried to define congestion, such as the work by the Texas Transportation Institute (TTI), and it is little surprise that TTI’s ranking of the most congested areas differs from INRIX’s. INRIX ranks the top five congested areas as Los Angeles, New York, Chicago, Washington DC, and Dallas. TTI ranks them (based on 2005 data) as Los Angeles, San Francisco, Washington DC, Atlanta, and Dallas. TTI bases its estimates primarily on survey data of travel habits and broad statistics such as traffic volumes and highway lane-miles. The flaws in this type of methodology have long been apparant, but no better alternatives existed. It will be interesting to see how INRIX's data is harnessed gonig forward to overturn other pieces of flawed conventional wisdom. Comments on this thought are encouraged.
In addition to better defining the congestion problem, INRIX’s data enables the pinpointing of specific trouble spots such as interchanges, construction zones, and merge lanes. The value of such cutting edge analysis is that it allows metro areas to identify and fix the flaws in their transportation systems. Experts and planners in the transportation community have long called for better data to help them understand and predict how transportation networks function, and that call is finally being answered by the sophisticated technologies of companies like INRIX. With more real data becoming available each day, let’s hope that real improvements in mobility soon follow.