Better Ways to Fix Traffic on Oahu

Honolulu drivers sitting under the shadow of a behemoth rail system have a lot of time to wonder, “What could’ve been done instead of rail?” Dr. Panos Prevedouros, Professor of Civil Engineering at the University of Hawaii at Manoa, has offered a number of solutions that could still be done – and wouldn’t cost very much.

What could Hawaii have done for the price of the rail? According to Dr. Prevedouros, simply updating the stoplight system would make a significant impact. By “tinkering” with the traffic lights, it’s possible to reduce traffic by 14,000 cars every year.


Another quick solution involves opening contraflow lanes, an idea that has been implemented on Kapiolani Boulevard with much success. By adding a few contraflow lanes on highly traveled routes such Nimitz Highway and Dillingham Boulevard, traffic capacity would increase by 55% in the mornings and 60% in the evenings. These two solutions — which could be implemented fairly quickly — would amount to less than 1% of rail costs.

Additionally, Dr. Prevedouros identified room for improvement within Hawaii’s infrastructure in the form of an underpass. Imagine approaching a red light; instead of slowing down, you continue underground and zip out on the other side of the road, and you haven’t lost any time.


This underpass in Lahore, Pakistan allows traffic to fly under without waiting for the stop light.

In 2004, Dr. Prevedouros pinpointed four highly congested intersections which were perfect candidates for an underpass system. By placing underpasses at these strategic locations, Oahu would see an 11% reduction in rush hour traffic time.

According to Dr. Prevedouros, building an underpass system would cost “peanuts” compared to the cost of the rail, at a mere $15 to $50 million. An animated simulation of the proposed Nimitz/Bishop underpass can be seen here.


Traffic simulation at Pali Highway and Vineyard Boulevard, before the underpass.


Traffic simulation at Pali and Vineyard after an underpass.

Traffic simulation at Pali Highway and Vineyard Boulevard after an underpass.

Other solutions mentioned by Dr. Prevedouros include an improved bus system, an elevated express lane, and a ferry system, all of which would have been less expensive than the rail, combined.

Even after implementing these solutions, the Department of Transportation could have constructed a $6 billion underwater tunnel from Ewa Beach to downtown Honolulu, and the cost would still be far less than current rail projections. Plus, an underwater tunnel would cut travel time from the west side to Honolulu down from 60 minutes to only 6 minutes!


Instead, Oahu drivers will likely see more traffic, even after the rail is completed. Dr. Prevedouros said, “By 2030, we’re going to have tremendous congestion, because essentially, we threw all our transportation money to a boondoggle that not a lot of people are going to use.”

For more solutions to Hawaii’s traffic problems, check out a video of Dr. Prevedours’ full lecture, “How to Solve Traffic Problems in Hawaii”.

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