Sure, the gasoline tax likely will be around for another 20 or 25 years. But Utah’s top transportation official said Tuesday that it will be replaced more and more by charging drivers for every mile they drive and by imposing more tolls.

“This is the future way,” Utah Department of Transportation Director Carlos Braceras told the Utah Taxpayers Association annual conference at the Grand America Hotel. “We’re going to fund [transportation] based on how much of the services you use.”

He said the shift away from the gasoline tax is needed for several reasons. Many hybrid and electric cars now escape it. Cars are getting better mileage, so they pay less in gas tax. And gasoline tax increases through the years have not kept up with inflation.

“Over the past 15 years, the purchasing power of the gas tax has gone down 70%,” he said. “We [at UDOT] have 200 less employees working for us right now than we did in the late ‘90s.”

Braceras said the state just took a first step away from gas tax with the new voluntary Road User Charge program that it launched on Jan. 1 for the owners of the 51,000 electric and hybrid vehicles in the state. It is only the second such program in America. The other is in Oregon.

Owners can choose to pay 1.5 cents for every mile they drive, usually measured by a transponder they plug in under the dashboard, paid automatically from a customer account connected to a credit card. They will be charged no more during the year than the amount of the higher registration fees such alternative-fuel cars face.

(David Zalubowski | AP file photo) A Nissan Leaf charges at a recharge station while parked by the Denver City County Building in downtown Denver in 2018.

“You keep more of your money in your pocket throughout the year and pay as you go,” Braceras said. “And you’ll never pay more than you do now anyway, and you may pay less if you drive fewer miles.”

He said the state hopes people will volunteer “because we have a lot to learn about this,” and how to overcome several problems.

For example, the state is still trying to figure out how not to charge people for travel outside the state or on private roads. It wants to help assure people that the state is not spying on nor tracking their individual movements. And the state is seeking ways to reduce the cost of administering the program (it hopes to break even by 2023).

Figuring out such obstacles is important, Braceras said, because lawmakers want the program expanded eventually to all cars.

“Members of the Legislature are very interested in pushing the program forward,” he said. “We’ve been directed that by Oct. 1 of this year, we have to submit a plan on how we would get all vehicles enrolled in this program.”

Despite that, Braceras said in an interview that he foresees the gasoline tax continuing easily for 20 or 25 years as a foundation for highway funding, but mileage charges and tolls “will make up some of that differential we are losing from cost inflation.”

He also said that tolling likely will be used more in the future, and the Legislature made recent changes to allow that.

“The Legislature wants us to consider tolling in the future more than we have in the past,” Braceras said.

UDOT is studying imposing tolls in canyons, in part as a way to control congestion on roads to ski resorts and encourage use of mass transit. UDOT also charges tolls to single-passenger cars to use the 80 miles of high-occupancy vehicle lanes on Interstate 15, and could eventually raise them to generate extra revenue.

(Al Hartmann | Tribune file photo) Traffic in the HOV lanes on I-15 on Oct. 6, 2018.

Also after passage of recent tax reform legislation, beginning on Jan. 1, 2025, cars will need three passengers instead of two to use the express or HOV lanes for free — meaning more people would need to pay tolls to use them.

Braceras notes that federal law bans imposing tolls on interstate highways except in HOV lanes or on turnpikes that predated the interstate system, such as in Pennsylvania, New Jersey and Ohio. He said that limits where tolls may be used.

“If you can’t toll interstates, there isn’t a lot of other roads where it makes sense to toll,” he said, limiting how much future tolls may raise.