But by the time paving began two months later, the project cost shot up about 40 percent. Now the price of liquid asphalt has almost doubled.

That means superintendents may want to hold off on any paving jobs, if possible.

The price has put the squeeze on paving contractors, and it means state and local governments are pursuing fewer road projects.

Robert Hill, senior vice president of Renfro Construction, said the cost of liquid asphalt has basically doubled in a year-from about $200 per liquid ton a year ago to the current price of about $400 per liquid ton.

In a typical ton of mix, liquid asphalt makes up only six percent of the volume, with the rest consisting of aggregate.

But in terms of cost, Hill said liquid asphalt accounts for 85 to 90 percent of the mix price, making it the key driver of paving costs.