Last spring, the Rhode Island Turnpike and Bridge Authority was putting the finishing touches on a high-tech system to automatically collect tolls from vehicles crossing the new Sakonnet River Bridge.

Last spring, the Rhode Island Turnpike and Bridge Authority was putting the finishing touches on a high-tech system to automatically collect tolls from vehicles crossing the new Sakonnet River Bridge.

This spring, as the General Assembly is poised to ban tolls on the span between Portsmouth and Tiverton, turnpike and bridge officials are preparing to the dismantle the system, facing a host of questions, not all of which have clear answers yet.

They say a portion of the state�s gas tax, about $15 million a year, will be enough to cover the money that would have been made on tolls.

They are not sure what they will do with the $2-million gantry and associated equipment that scans E-ZPass transponders and photographs license plates of vehicles that don�t have E-ZPass.

They say drivers won�t be able to get a refund on E-ZPass transponders, costing as much as $20.95, they no longer need.

They are not sure what they will do about an estimated $250,000 that people without transponders have incurred in tolls.

They are not sure exactly when they will stop collecting tolls.

In special hearings last fall and throughout its 2014 session, the General Assembly has been trying to figure out a way to eliminate the Sakonnet tolls and still provide enough money to pay for maintenance of the four bridges under control of the Turnpike and Bridge Authority: the Sakonnet River Bridge; the Pell Bridge, which connects Jamestown and Newport; the Jamestown-Verrazzano Bridge, connecting Jamestown and North Kingstown; and the Mount Hope Bridge, between Bristol and Portsmouth.

The first proposal to emerge from lawmakers called for eliminating the tolls and all but doing away with the Turnpike and Bridge Authority, putting the four bridges under control of the state Department of Transportation and making the authority a division of DOT charged with collecting tolls on the Pell Bridge.

A revised plan also eliminated the tolls but kept the authority as a separate state agency. That proposal would have shifted maintenance of two of the four bridges to the DOT.

The latest proposal, part of the state budget under discussion by the House of Representatives on Thursday night, keeps the authority intact and in charge of all four bridges. The main change is doing away with the Sakonnet tolls and replacing the money with a portion of the gasoline tax.

Currently, people who get gas in Rhode Island pay 51.4 cents a gallon in taxes. Of that, 18.4 cents goes to the federal government and 33 cents to the state. If adopted, the Sakonnet plan would dedicate 3.5 cents a gallon of the 33-cent tax to the Turnpike and Bridge Authority.

That would generate �just shy of $15 million,� Sen. Louis P. DiPalma, a Middletown Democrat who has been a main proponent of eliminating the toll, said in an interview Monday.

�It appears that would be adequate,� Earl J. �Buddy� Croft, executive director of the Turnpike and Bridge Authority, told The Providence Journal Wednesday. �It would appear it would give us the wherewithal to maintain the four structures to keep them safe.�

The same portion of the state budget that eliminates the tolls and sets aside gas tax money for the authority also alters the 33-cent gas tax, automatically increasing it by the amount of inflation every two years. But the bill does not include automatic adjustments for the 3.5 cents that go toward the Turnpike and Bridge Authority.

So what happens if bridge-maintenance costs rise over the years or inflation erodes how much maintenance the 3.5 cents will buy?

�Come back and have a discussion: Is more needed or not? Or is less needed?� said DiPalma. �If more money�s needed, when is it needed and how much is needed?�

He said that bridge-maintenance costs fluctuate from year to year as major repair projects are undertaken, but then don�t need to be repeated for years, sometimes a decade or more. Because of that variability, DiPalma said he figured the amount of the gas tax going to the bridges would have to be adjusted periodically.

�Do I think it�s every year? No,� DiPalma said. �Do I think it�s every five years? Yes.�

Last Aug. 19, the Turnpike and Bridge Authority began collecting a 10-cent toll on the Sakonnet River Bridge. The agency had planned a much higher fee � 75 cents to $5.25, depending on where drivers lived and whether they had an E-ZPass, but residents and businesses on Aquidneck Island protested, saying the toll would cost them money and drive away customers.

In response, the General Assembly voted to abolish the toll altogether. But legislators reversed themselves almost immediately, imposing the 10-cent toll as a �placeholder,� under the belief that federal regulations would not allow tolls on the new bridge if it did not have one at the outset.

The 10-cent rate was to expire in April. The Turnpike and Bridge Authority planned to increase the toll then to 50 cents for drivers with a Rhode Island E-ZPass and $3.75 for all others, but that was put on hold while the legislature worked on the plan embodied in the state budget.

Throughout the controversy, the authority has collected tolls to cross the Pell Bridge and will continue to do so after the Sakonnet issue has been resolved.

Croft said the authority has collected about $700,000 in 10-cent tolls from motorists using E-ZPass transponders. Those without transponders have incurred another $250,000 in tolls, he said. The agency has not yet billed people, whose tabs have been tracked by their license plate numbers.

Croft said the agency will decide what to do about the outstanding $250,000 at its July board meeting, adding that the board is considering sending bills to those who owe money.

As for people who bought E-ZPass transponders just to cross the Sakonnet River Bridge, they now own them, Croft said. The agency won�t make a special policy when the toll goes away. The usual policy regarding transponders will be enforced: Motorists can return them for a refund only if the transponders have not been used to drive through a toll.

And what becomes of the gantry, the metal arch poised over the highway to record E-ZPass and license plate numbers?

�That�s a decision the board�s going to have to make,� Croft said. It has cost more than $4 million to install, equip and operate the structure.

Lastly, when will the authority stop collecting tolls on the Sakonnet River Bridge? Croft said his agency would look to state law for guidance on that. The proposed budget ends the toll on June 30.