Motorists crossing the Mount Hope Bridge between Portsmouth and Bristol may soon have to pay a toll.

The Providence Journal / BOB THAYER

Tolls at the Claiborne Pell Bridge may be going up for motorists who don’t own an E-ZPass transponder purchased in Rhode Island.

And the Mount Hope Bridge, free to cross since 1998, could see a return to its long history of collecting tolls.

David Darlington, chairman of the Rhode Island Turnpike and Bridge Authority, will recommend to his board Wednesday that it hold public hearings and adopt a plan to raise the tolls.

The agency, he said, should also do what other states do and raise tolls automatically, every three years.

“The safety of the bridge must remain our highest priority,” Darlington said in a statement. “We simply don’t have the resources necessary to maintain them without this increase.”

Darlington says the toll increases — the first in the history of the Newport bridge — are necessary to pay for future bridge improvements and to prevent a $223-million shortfall over the next 20 years.

Darlington will also recommend a formal study on reinstituting tolls at the Mount Hope Bridge, an idea suggested when the agency held public hearings last year on the financial challenges it is confronting. Users of the Pell Bridge said it wouldn’t be fair if improvements at the Mount Hope Bridge were financed solely with tolls from the Newport-Jamestown span.

In 1998, the authority eliminated tolls at the Bristol-Portsmouth span after determining that the amount of toll revenues only slightly exceeded what was spent on salaries of toll collectors and other expenses. The tollbooths were demolished the following year.

Under Darlington’s proposal, the toll to cross the Newport span would increase from $2 to $4 for those paying cash. For those with E-ZPass transponders from out of state, the toll would go up even more, from $1.75 to $4. Tolls for commercial vehicles would increase $1 per axle.

Owners of Rhode Island transponders would continue to be charged 83 cents per crossing. Motorists with out-of-state transponders who commute regularly over the bridge — at least 30 times a month — also would be spared an increase. They would continue to pay 91 cents per crossing.

E-ZPass debuted in Rhode Island in January. Darlington said at the time that rates weren’t going up immediately because “E-ZPass has nothing to do with a toll increase. It’s how we collect tolls, not how much the toll is.” He said that the projected budget shortfall might require toll increases in the future.

A Rhode Island transponder may be purchased for $20.95 for the kind mounted inside a vehicle or $33.04 for one mounted to a vehicle’s exterior.

rsalit@projo.com