PUHI, Kaua'i — A two-year, $39 million project to widen Kaumuali'i Highway from Lihu'e to Puhi to four lanes was kicked off with a groundbreaking ceremony on Wednesday.

Contractor Kiewit Pacific Co. will build Kaua'i's first Portland Cement concrete highway on the two-mile stretch of road from the Anonui Road intersection, west of the Kaua'i Community College, to the Lihu'e mill bridge.

The work, a state project, will include improved intersections and sidewalks to make the highway more pedestrian-friendly, the state Transportation Department said in a news release.

"This widening project will essentially double the capacity of the Kaumuali'i Highway for commuters heading in and out of Lihu'e," state Transportation Director Brennon Morioka said in the announcement.

The 2-foot-thick concrete roadbed proved to be a cost-effective choice over the projected 30- to 50-year life of the highway, Morioka told The Advertiser.

With higher oil prices, the comparative cost of an asphalt highway, which requires more maintenance, is approaching that of a concrete road, which requires less maintenance, he said.

A recently completed surface for Kapule Highway near Lihu'e Airport used a 6- to 8-inch-thick concrete topping, Morioka said.

The two-year Kaumuali'i project is the first phase in widening the Kaumuali'i Highway from Lihu'e to Maluhia Road, the southbound road to Koloa and Po'ipu.

The first stage of the widening project will be to add lanes near the Aloha Church, the DOT says. The second phase will be widening the makai side of Kaumuali'i Highway from the Lihu'e mill bridge to Nani Street.

Two lanes of traffic will be open through the majority of the work, Morioka said.