LANSING –State gas-tax revenue is falling and Gary Dittmer is feeling the pinch.

Dittmer, the director of the Mason County Road Commission, has left job vacancies unfilled, put equipment purchases on hold and postponed road work.

"Our main issue is funding," he said. "It's starting to get critical," adding that his agencies funding is down by about $150,000 from 2005.

Counties across the state are facing similar situations similar to said John Niemela, director of the County Road Association Michigan.

Revenue generated from the state gas tax isn't keeping up with the cost of repairs and equipment, he said.

"The combination of less revenue and higher costs has been a struggle for a lot of the road commissions," Niemela said.

From January to July, the state collected $520 million from the gas tax. That was $5.2 million less than in 2005 and $13 million behind 2004 revenue. The state collects 19 cents for every gallon of gas a driver pumps, and counties receive 6 of those 19 cents.

"That clearly hasn't kept up with overall costs," Niemela said, adding that higher gas prices and fuel-efficient vehicles may contribute to the declining revenue.

The lack of funding left Dittmer with enough money to repair only half of a 2-mile section of Jagger Road in Hamlin Township, near Ludington.

"It's in a really deteriorated condition," he said, adding that he is looking for money to fix the other half.

But while gas tax revenue is shrinking, Niemela said, equipment costs are rising.

For example, Dittmer said that asphalt costs about $45 a ton, which is $15 more than in 2005. Asphalt is used in many road projects, including filling potholes.

"That's a tremendous jump," Dittmer said

And Niemela said it's those rising costs that have forced county road commissions to be more selective when choosing projects, Niemela said.

Niemela said one way to address the funding problem is raising the gas tax.

He said he'd like to see the tax, which was changed to 19 cents per-gallon in 1997, climb to 28 cents. That could be done by increasing the tax by 3 cents each year for three years, Niemela said.

"We look at it as being essential," he said.

Niemela said he expects to see a gas tax hike proposed sometime after the new Legislature meets in January.

But getting the public and the Legislature's support behind the gas tax hike will be difficult.

People react negatively anytime they hear about a tax increase, said Rep. Phil LaJoy, chair of the House Transportation Committee.

"They would need a real good campaign telling people what was going to happen," the Canton Republican said. "You would have to make people satisfied that what you were going to use would benefit them."

Such a proposal, LaJoy said, would likely generate controversy because it would raise gas prices.

"This is something that's going to be debated, and I think it needs to be thoroughly debated," he said.