Urban traffic jams will choke North Carolina's economic growth unless state and local leaders push to unclog city streets and freeways, a UNC-Charlotte transportation professor said in a report released Monday.

David T. Hartgen said the state should realign spending priorities to focus on slowing the growth of traffic congestion, which is expected to double in the next 25 years.

Priorities for the Triangle, he said, should include finishing the Interstate 540 Outer Loop and finding a smart way to expand the capacity of I-40 as it squeezes through Research Triangle Park. Hartgen also called for efforts to synchronize city traffic signals and to reduce rush-hour traffic with carpooling, flex scheduling and telecommuting.

In a review of road conditions and growth trends in 17 cities, he said Charlotte and the Triangle face the worst traffic jams but are not alone.

"We're actually a very urban state," Hartgen said in an interview. "People don't think of us as urban, but we are. Even in relatively small towns, congestion has become quite a serious problem."

His 234-page report was funded by the John Locke Foundation, a conservative think tank based in Raleigh. Consistent with previous Locke reports, Hartgen said North Carolina should cut spending on public transit and make better use of highway dollars before seeking new sources of transportation money.

"I don't know whether we need more money here," he said. "What we do need to do first is look at how our plans are structured."

William A. "Beau" Mills, who lobbies the General Assembly on behalf of the state's biggest cities, praised Hartgen for spotlighting the problem of highway congestion.

"We are in the midst of a perfect storm here in North Carolina with population growth in our urban areas, runaway inflation for transportation construction and diminishing resources to help solve these problems ... ," Mills said. "The question is, how do you find the resources to do that? I don't think he has quite answered that question."

The General Assembly is considering proposals to steer more state money to road needs and to let local governments levy new taxes for transportation and other capital improvements. Hartgen agreed with urban leaders who want legislators to make traffic congestion a key factor in allocating transportation dollars across the state.

He said one possible I-40 solution could involve building new lanes on stilts above the median and reserving them for buses, carpoolers and toll-paying solo drivers. Some cities make such lanes reversible, changing direction to match the rush-hour ebb and flow.

With daily traffic counts expected to rise from more than 100,000 cars and trucks now to 170,000 or more in the next 25 years, he said, I-40 is the Triangle's biggest traffic challenge.

"We basically have stuck our head in the sand on this and have not thought enough about what clearly is going to be the central issue here," Hartgen said. "Clearly, what we have planned there is not going to be adequate."

A statewide report says highway spending must focus on slowing the growth of congestion.

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