Transportation >> Commuting >> Traffic Congestion Trends

Traffic congestion cost King County drivers an average 48 hours in 2011.

Commuting by public transit, on bicycle, or on foot boosts physical activity, reduces traffic congestion, and decreases auto emissions that contribute to air pollution.  Traffic delays increase overall stress and costs – of food, clothing, building materials, and everything else that is transported on roads.

  • In 2011, commuters in the Seattle/Tacoma/Everett corridor lost an average of 48 hours to traffic congestion -- 10th worst among large metropolitan areas.
  • Congestion delay was down from a peak of 55 hours in 2005.
  • The total cost of travel delay is near its peak, however.  Computed at the rate of $16.79 per hour of “person travel” and $86.81 per hour of “truck time,” plus the cost of excess gasoline and diesel, the local inflation-adjusted cost of traffic congestion in 2011 was $2.24 billion.
  • Freeway traffic in metropolitan King County is unpredictable.  Because of this volatility, rush-hour drivers need to multiply “light-traffic” travel times by 3.99 if they want to get to work on time 19 out of 20 days in the month. This means setting aside an hour for a trip that would take 15 minutes in light traffic.