PORTLAND -- An annual study of traffic flow worldwide ranked Portland as the 8th worst city in the U.S. for congestion on arterial roads and highways.

The TomTom Traffic Index tracked time delays for drivers, peak traffic hours and congestion levels in 53 metropolitan areas with populations over 800,000.

The research found that Portland drivers were most likely to get caught in backups during the morning commute on Thursdays and Fridays.

It also found that the worst nights for evening rush hour gridlock were Mondays and Thursdays.

Dave Thompson with the Oregon Department of Transportation said while Portland does have some delays, he didn't think researchers made fair comparisons in choosing the high ranking.

The way they measure it does not take into account that we actually have a shorter distance in our commute, he said. Their mathematical technique is actually biased towards cities with longer commutes.

Los Angeles was ranked as the most congested city in the U.S. Seattle was 4th worst in the U.S. and 7th in the world. Portland was ranked as 13th worst in the world and Rio DeJaneiro was number 1.

It will be interesting to see how cities and drivers react to our findings. In the meantime, our research helps keep a pulse on the shifts in traffic patterns, as we work to find new ways to tackle congestion, said TomTom s Head of Global Traffic Research, Nick Cohn.

ODOThas already been able to pinpoint the most congested intersection in Portland, where more than 171,000 vehicles pass through. Thompson identified it as Interstate 84 at Northeast 33rd Avenue - in both directions.

The TomTom Index is used as a tool for city planners evaluating areas in need of upgrades or changes to improve traffic flow.

TomTom is a global supplier of in-car location and navigation products and services.

Get speed maps, traffic cams and more on-the-go with the FREE Portland Traffic app

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