A week after a highway bridge collapsed in Minneapolis, Gov. Tim Pawlenty is re-thinking his opposition to increasing Minnesota’s gas tax. Tough discussions and new thinking about road funding are likely in state capitals around the country, Augusta included.

Earlier this year, Gov. Pawlenty vetoed legislation to raise Minnesota’s gas tax to pay for road and other transportation work. The 5-cent increase had been supported by many businesses, including trucking companies, that viewed the additional spending as a needed economic development investment.

The collapse of the Interstate 35W bridge, which killed five people and left eight missing, put safety at the top of the list for politicians now championing increased transportation spending. A spokesman for Gov. Pawlenty said the governor is now open to a gas tax increase.

In Maine, the state’s gas tax is automatically increased each year unless the Legislature votes otherwise. Nearly every year, there is an effort to stop the indexing in the name of lowering taxes and saving consumers money.

This year’s increase, which took effect July 1, raised the tax by about nine-tenths of a cent to just over 29 cents per gallon of gasoline.

A further complication is that the tax covers a shrinking portion of Maine’s road needs as the cost of construction materials and the fuel needed to power equipment has risen faster than the gas tax. The same is true in other states. For the first time in more than two decades, spending on major highway improvements nationwide declined in 2004.

So it is not surprising that about 12 percent of the nation’s bridges, including the I-35W bridge, are rated “structurally deficient,” defined as having major deterioration, cracks or other flaws that reduce their ability to support vehicles, by the Federal Highway Administration. About 14 percent in Maine are.

Faced with growing problems and shrinking revenue, officials and politicians are looking to additional sources of revenue. The National Conference of State Legislatures is calling for a 3-cent per gallon increase in the federal gas tax.

A University of Maine study on sustainable transportation funding offered other options, including local option transportation taxes, congestion pricing, a per-mile charge, an added tax on heavy vehicles, adding variability to registration fees and an emissions fee. None of these would be popular, but a diversified transportation funding source is overdue.

Maine has a $1 billion backlog of road and bridge repairs. Many of these projects have languished on Department of Transportation lists, waiting for funding. Highway projects are funded, in addition to federal dollars, from the state’s highway fund and by bond issues. The highway fund gets nearly 70 percent of its money from fuel taxes.

Maine ranked 17th in terms of cost-effectiveness in 2004, according to an annual assessment of the conditions of the country’s roads and bridges by University of North Carolina at Charlotte professor David Hartgen, a Maine native.

One way the department has made do with less money is to repair roads and bridges that, in better economic times, should be replaced. As a result, maintenance accounts for 23 percent of DOT’s budget, the eighth highest proportion in the country, according to Professor Hartgen.

The ongoing transportation budget crunch coupled with Maine’s backlog of road and bridge repairs and improvements add urgency to the discussion of diversifying the ways highway work is funded.