With spring road construction about to begin, paving contractors in New Brunswick are playing their annual guessing game about the cost of liquid asphalt, and some wonder why it remains so expensive.

Liquid asphalt is a petroleum product that binds sand and stone together and then hardens to make asphalt cement.

In 2007, the cost was about $450 a tonne, and by the end of summer 2008 it was more than double that.

"Liquid asphalt went up to well over $900 a tonne, and then it stayed there even when the fuel prices returned to more of a normal price," said Murray Jamer, director of engineering and public works for the City of Fredericton.  

"Last year, for the first time that I can remember, there were actually a few of our streets that didn't get done because we would have gone over budget," he said.

Most of the liquid asphalt used in New Brunswick is produced by the Irving Oil refinery in Saint John, and Mike Linton, who owns the paving company Durapave, said he can't understand why it costs so much.

"It certainly seems to me that it's one of the less-refined products that you could produce. You know, it makes it even more, well, somewhat frustrating, and a little bit bewildering, I guess," Linton said.

Meanwhile, this year's liquid asphalt price won't be set for another month, but contractors have to bid now on paving projects. So they have to base their bids according to what they guess the price will be.

Janice Buchanan, community relations spokeswoman at the Irving refinery in Saint John, told Fredericton's Daily Gleaner recently that the refinery is at the mercy of market prices for the crude oil it refines into different products.

"We don't set the prices," Buchanan said.