|  Share | Cite

Major Causes of Traffic Congestion in the U.S.

Bottlenecks (traffic demand
 exceeds roadway capacity)
50% of total congestion
Traffic incidents25% of total congestion
Work zones15% of total congestion
Bad weather10% of total congestion
Poor signal timing 5% of total congestion
Source: American Highway Users Alliance, Unclogging America's Arteries, 1999–2004. Web: www.highways.org.

Information Please® Database, © 2007 Pearson Education, Inc. All rights reserved.

Traffic Congestion in U.S. Cities, 2002TransportationAmerica's 24 Worst Highway Bottlenecks