Most of Oahu's roads are paved with asphalt. Here's why that's a problem

HONOLULU (HawaiiNewsNow) - Most of Oahu's highways and streets are paved with asphalt.

But University of Hawaii Civil Engineering professor Amarjit Singh thinks that type of surface is reaching the end of the road.

"We won't have asphalt roads in about 30 years or so," he said.

Asphalt for paving comes from petroleum crude oil. Singh theorizes that the world's oil is running out so now is the time to switch to concrete paving

"Concrete surfaces will remain steady while asphalt will deteriorate a little faster," he said. "This has been proven time and time again over decades of experience."

The state is in the process of installing hundreds of concrete pavement panels across a two-mile section of the H1 Freeway between Halawa and Pearl City.

The project is costing nearly $64 million.

By comparison, the state estimates costs $750,000 to repave one mile of highway with asphalt.

Singh believes concrete delivers a better return on investment.

"If you buy an asphalt road you have to suffer the consequences of asphalt, and that means frequent repairs, much more than repairing concrete," he said.

The city also uses concrete on streets and roads that carry heavy traffic.

But there are drawbacks. Concrete takes longer to install and makes it harder to repair utilities beneath the pavement.

Going forward the state Transportation Department says it will strategically select more highways for concrete paving. HDOT plans to change the outside lanes on Nimitz Highway and Ala Moana Boulevard to concrete to better withstand pounding from heavy vehicles.

Singh hopes more roads and highways convert to concrete.

"So long as your construction is good concrete is going to last you a long, long time," he said.

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