Which American city has the worst traffic? If you said New York or Los Angeles, guess again. A new survey by TomTom, which is based on the traffic data of millions of GPS users, finds Seattle has the highest percentage of congested roadways.
The results come from TomTom’s speed profiles, an historical speed database from TomTom map business unit Tele Atlas. The profiles aggregate the actual speeds that millions of anonymous, GPS-enabled drivers have traveled over the last two years.
Cities were ranked as most to least congested according to how fast cars could travel on the street network. A city’s traffic was defined as congested if drivers could travel at only 70 percent or less of the posted speed limit, meaning on average an hour long commute included 20 minutes or more of significant delays.
According to TomTom, the numbers contained some surprises:
✓ Seattle is the city with the worst traffic in the United States, with an average of 43 percent of its roads showing heavy delays. Rounding out the top five cities after Seattle are Los Angeles (38 percent), Chicago (37 percent), San Francisco (35 percent); and New York (31 percent).
✓ California’s Bay Area has the most cities in the top 30, with San Francisco, San Jose (29 percent) and Oakland (28 percent).
✓ The most congested corridor is between Baltimore and Washington, D.C. About 36 percent of that area’s roads, largely in Montgomery County, are congested.
✓ While New York has many pockets of heavy congestion, the area also contains many major arteries for alternative routes. In fact cities with fewer options for alternative roads were higher on the list.
The least congested of the top 30? Charlottesville, Va., where only 19 percent of the roads in that city are congested.
Here’s the full list:
1. Seattle (43%)
2. Los Angeles (38%)
3. Chicago (37%)
4. Montgomery County, MD (37%)
5. San Francisco (35%)
6. New York (31%)
7. Washington (30%)
8. San Jose, CA (29%)
9. Alexandria, VA 28%
10. Oakland, CA (Alameda County) (28%)
11. Atlanta (Cobb County) (27%)
12. Boston (27%)
13. Fairfax County, VA (26%)
14. Philadelphia (25%)
15. Austin, TX (25%)
16. Phoenix, AZ (25%)
17. Long Island, NY (Nassau County) (24%)
18. San Juan, Puerto Rico (24%)
19. Portland, OR (23%)
20. Houston (23%)
21. Contra Costa County, CA (23%)
22. Arlington, VA (23%)
23. Orange County, CA (20%)
24. New Orleans (20%)
25. Norfolk County, MA (20%)
26. Denver, CO (20%)
27. Morris County, NJ (20%)
28. Miami-Dade, FL (20%)
29. Dallas, TX (20%)
30. Charlottesville, VA (19%)
(Photo: Splorp/Flickr Creative Commons)
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{ 13 comments… read them below or add one }
Yep, Phoenix definitely has some of the worst traffic. You’d be surprised how many accidents occur each day. When you travel in Phoenix, be very careful because the people are in a big hurry and they will let you know it!
This confirms what I have long suspected. Montgomery County, MD, Washington, DC, Fairfax County, VA, Arlington, VA, and Alexandria, VA may as well be the same place. I’m no geography major, but I suspect that the area encompassed by these five areas is not much bigger than the Greater Los Angeles Area. And they’re all smashed together around a Beltway that was obsolete when it was completed in 1954. We don’t get the “publicity” of LA Traffic, but…….Sheesh! What a mess!
No surprise that San Jose and San Francisco are near the top of the list. We really suffer major delays here. Even in the peak of the recession, traffic was still heavy. Last night it took me 1 hour to get home from work (only 12 miles!!).
Charlottesville? Charlottesville is on that list? I mean, I joke when I say that no one knows how to drive, but 29 cant possibly be that bad, can it?? Wow. Another argument for the Meadowcreek Parkway.
I’m pretty surprised to see Charlottesville on that list, but the rest is not surprising. Amazing how many of those cities I have actually been to.
I’m surprised Atlanta (Cobb County) isn’t higher on the list. Whenever something happens on a major road, the alternative routes are always jammed up very quickly afterwards. Driving during rush hour is like racing in the Indy 500.
Hey, where’s Vegas? This city has some of the worst traffic and drivers I’ve ever seen. And I’ve driven in LA, Seattle, Toronto, Vancouver (a nightmare in itself but it’s Canadian so not on this list), and Denver.
“In fact cities with fewer options for alternative roads were higher on the list.”
As a Seattle resident, it doesn’t surprise me that we are at the top of the list. We’ve had a great deal of urban growth over the years and the infrastructure hasn’t kept up. A big part of the problem is geographical. Hills and lakes are difficult to build freeways over. One stalled car on the 520 bridge (2 lanes each way) and there goes the evening commute. Weather doesn’t help either–rain or strong winds brings traffic to a near stop.
i can’t believe the honolulu/waikiki areas are not on the list. we have so few road options that a completely innocuous event like a stalled out car will congest the highway for hours. and don’t even consider taking surface streets; everyone else had the same idea with the added incentive of a traffic signal every 100 feet or so. it actually took me two hours to get from hawaii kai to honolulu once during the height of rush hour in the morning. i actually plan my errands around “who’s open how late?” to try and be able to do my shopping at midnight when everyone else is asleep.
Calling a road backed up when speeds drop to 70% of posted speed is not very realistic. 70% of posted speed around the north side of the Capital Beltway in the afternoon would be a dream. Never gonna happen though. Maybe the “Lexus Lanes” will save us. Yea, right!
@✓ California’s Bay Area has the most cities in the top 30, with San Francisco, San Jose (29 percent) and Oakland (28 percent).
The Washington-Arlington-Alexandria-Fairfax-MoCo group covers about the same area as SF-SJ-Oakland (10 “zoom outs” on a Google map); wouldn’t that region have the most entries in the top 30? I suppose they’re not all “cities,” but still.
This person has never been to Birmingham, AL, obviously. I travel for work nationally at least once a month and Bham has aweful traffic.
Hampton Roads is terrible. Way too sprawling. Not enough tunnels and needs heavy rail, not the do-it-on-the cheap light rail system Norfolk is building.