Advocate staff photo by HILARY SCHEINUK -- The sun sets behind the Horace Wilkinson Bridge and the Mississippi River in downtown Baton Rouge on Monday.

Just ahead of a key vote, a panel named by Gov. John Bel Edwards endorsed two ways to finance state transportation projects Wednesday, including a new bridge over the Mississippi River in Baton Rouge.

One of the resolutions calls for the state to initiate public/private partnerships to help finance costly plans, including one for the bridge, which would cost more than $1 billion.

Such arrangements involve private firms helping finance construction costs in exchange for future revenue through tolls or other sources.

The other option recommended is tolls, which are often discussed but rarely used in Louisiana.

Both measures are supposed to serve as supplements to the key funding source, which is expected to be an increase in the state gasoline tax.

"The tolling option is just part of the package," said Shawn Wilson, secretary for the state Department of Transportation and Development and co-chair of the committee.

The group — called the Governor's Task Force on Transportation Infrastructure Investment — is set to begin debating possible gas tax hikes and other proposals on Dec. 1.

Recommendations are due to Edwards by Jan. 1, and the governor is expected to make transportation a key issue for the 2017 regular legislative session.

The 18-member panel is grappling with twin challenges.

The state has a $13.1 billion backlog of road and bridge needs.

In addition, a new bridge and other mega projects make up a separate, $16 billion list.

Leaders of seven trade groups pleaded with the task force to come up with recommendations that can make a dent in both agendas.

"An increase in the gas tax is the best source of new transportation funding," said Scott Kirkpatrick, executive director of a Baton Rouge-area transportation advocacy group called CRISIS.

Kirkpatrick also said tolls "are certainly something the public and businesses are open to."

Motorists pay 38.4 cents per gallon in Louisiana, including 20 cents in state taxes.

Each penny hike would raise about $30 million per year.

Derrell Cohoon, representing the Associated General Contractors, said AGC would support a legislative push for more transportation dollars.

"It's been great to see a governor in strong support of this issue," Cohoon told the task force.

Pat Dorsey, who is part of a group of residents on the west side of the river who favor a new bridge, told the group that bridge backups cause daily horrors for motorists.

Dorsey, who lives in Iberville Parish, said that after she took a fall recently, the ambulance driver pleaded against taking her to Baton Rouge General Hospital — her choice — in favor of a hospital near Plaquemine, citing bridge traffic.

House Transportation Committee Chairman Kenny Havard, R-St. Francisville, a member of the task force, said it would be a mistake for the panel to put too much emphasis on boosting the gas tax.

"We need to have options other than putting all of our eggs in one basket," he said. "Let's throw everything at the wall and see what sticks."

Havard said he is researching the possibility of a refinery tax to generate dollars for roads and bridges.

Bob Schmidt, who represented the American Council of Engineering Companies, said even the often-cited $600 million annual target figure for new transportation dollars would not be enough.

Schmidt said officials need to devise ways to leverage any new gasoline tax revenue to tackle more projects.

Follow Will Sentell on Twitter, @WillSentell.