Los Angeles traffic remains the most congested of any city in the U.S. and Canada, according to a survey just released. Trip times in Los Angeles are 33% longer, on average, than when traffic in the city is flowing freely, and a whopping 74% longer during evening rush hour. Other congested cities include Vancouver +33%, San Francisco +29%, Montreal +28%, Toronto +27%, Washington +26%, Seattle +26%, New York +25%, Chicago +23% and Miami +22%. A study by the United States Department of the Treasury claims that congestion consumed an extra 1.9 billion gallons of fuel in 2011, approximately 5% of all gasoline used.
The latest so-called Congestion Index covering 26 cities from TomTom is based on real-time data captured by vehicles driving on the entire road network in metropolitan areas. This traffic database now has more than six trillion measurements, and is growing by about five billion measurements every day. The overall congestion level for all the North American cities analyzed between April and June 2012 is +21%. The European level is +23%. Data collected are anonymous and used for developing navigation systems that quickly adjust routes to changing traffic patterns.
The Congestion Index compares travel times during non-congested periods (free flow) with travel times in peak hours. The difference is expressed as a percentage increase in travel time. The Index takes into account local roads, arterial roads, as well as highways. All data are based on actual GPS based measurements. To download the North American (TomTom apparently ignores Mexico) and European Congestion Index reports, go to www.tomtom.com/congestionindex.