Fifteen months and tons of concrete later, the barricades are down and traffic on Provo-Orem hill is flowing smoothly.

The $3.4 million project paved 1.1 miles of State Street and created a six-lane highway that should handle increased traffic with minimal maintenance for the next 30 to 40 years. Crews poured 56,500 square yards of concrete and set it 11 inches deep.Officials said using a thick layer of concrete rather than normal asphalt is a relatively new idea.

"It is being used more and more around the country but is not too common yet," said Dan Nelson, director of Utah Department of Transportation's District 6, during a Friday morning ribbon-cutting ceremony. "It is something we can be proud of. I'm sure people from other cities will come by to see how it works out," he said.

"It will save a myriad of problems over asphalt."

John Beal, spokesman for the Provo-Orem Hill Merchants Association, said business owners had been worried about inconvenience to shoppers.

"We did realize some problems, and business was curtailed a little, but things went better than we thought."

Beal said he was happy to see State go from a two- to a six-lane highway before his eyes, and he hopes business in the area will increase because of it.

Kevin Beckstrom, a UDOT spokesman, said State Street is used by about 30,000 vehicles a day.

"It might have dropped a little during construction, but should pick up again now," he said.

The ceremony was attended by Provo Mayor Joe Jenkins, Orem Mayor pro-tem Joyce Johnson, highway officials, owners of local businesses and others who helped with the project.