Major Causes of Traffic Congestion in the U.S.
Updated August 5, 2020 |
Infoplease Staff
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Bottlenecks (traffic demand exceeds roadway capacity) | 50% of total congestion |
Traffic incidents | 25% of total congestion |
Work zones | 15% of total congestion |
Bad weather | 10% 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.
Traffic Congestion in U.S. Cities, 2002 | Transportation | America's 24 Worst Highway Bottlenecks |