AUGUSTA – No elected official wants to be culpable in the collapse of a bridge.

But in an era of fewer federal dollars returning to state departments of transportation, and bridge and road construction costs growing by 35 percent between 2004 and 2007, public safety comes down to money.

The phrase “aging transportation infrastructure” could be applied to virtually any state in the U.S. It certainly is applicable in Maine, with 40 percent of the state’s bridges at 50 years old or older.

Near the end of the legislative session in 2006, some members of the Transportation Committee talked about a bond issue to raise funds for road and bridge work. Republican legislative leaders responded by invoking an agreement from the first year of the session, which meant no bonds would be put forward in 2006.

This spring, though, members of both parties agreed to propose a $113 million transportation bond – the largest in state history – and voters approved it by a more than 2-to-1 ratio on June 12.

Still, funding for road and bridge work remains a concern.

Sen. Dennis Damon, D-Trenton, proposed a bold restructuring of the source of transportation funds, moving it away from reliance on fuel taxes, which are flat or declining as people drive less and buy more fuel-efficient vehicles.

LD 1790, which went into legislative limbo at the end of the spring session, called for dipping into the sales tax on vehicles and the excise tax paid when a vehicle is registered and directing the revenue to the Maine Bond Bank. A trust fund would be created that then could be tapped by the Legislature for road and bridge work.

The measure was difficult to sell politically, since it created holes in the state General Fund.

At a press conference Thursday, Gov. John Baldacci highlighted the importance of securing a stable funding source for road and bridge work.

“It’s important to the public safety,” he said, and argued that “it shouldn’t take a couple of years to get a bond issue.”

He also reported that a joint committee of members of the Appropriations and Transportation committees were working on LD 1790.