BOISE - Total highway spending in Idaho has dropped nearly 20 percent in recent years, a dip that has compounded the state's road funding problems and added urgency for lawmakers seeking a solution.

One of the major reasons for the drop is an 8 percent decline in federal money. The state received $321 million in federal road funding in 2010.

By 2013, that number had fallen to $295 million.

Similarly, total highway spending in Idaho was $959 million in 2010, but it dropped to $791 million by 2013.

The reduction mirrors a national trend in which decreasing federal dollars have stalled road upkeep across the country, according to a review of data from The Associated Press.

Lawmakers have said current funding levels aren't enough to maintain Idaho's crumbling roads and bridges. A governor's task force said in 2010 that the state faced a $262 million annual shortfall for maintenance work and another $281 million would be needed each year to pay for improvements.

The Legislature hasn't passed any new taxes to fund road work since the committee released its report, and officials say the state is now bringing in less revenue for transportation infrastructure than it was then.

Gas taxes, a major source of road project funding, haven't increased in Idaho in 20 years, and the revenue they generate hasn't kept pace with inflation or increased use of state roads.

Lawmakers have discussed funding problems for years, but Republican Sen. Bert Brackett of Rogerson, who chairs the state's Senate Transportation Committee, says he's "very optimistic" there will be progress this session.

"In the past two years, we've spent a considerable effort educating the public, as well as our colleagues," Brackett said. "I think public opinion has recognized there's a need."

The House Transportation and Defense Committee, meanwhile, has introduced a plan that would raise fuel taxes and registration fees to generate almost $200 million per year. The proposal calls for a gas tax increase of 8 cents.

Republican leadership is working on an alternate plan, Majority Caucus Chair John Vander Woude said.

The Nampa Republican said the plan would raise the sales tax, eliminate the grocery tax and institute a flat tax to come up with revenue for road projects.