LOUISVILLE, Ky. (WDRB) – Adding tolls to Indiana’s interstates could generate billions of dollars as the state braces for declining revenues from fuel taxes, according to a report released this week.

But charging drivers between 4 cents and 63 cents per interstate mile also could lead to increased traffic on other routes, which can result in wear and tear on aging roads and bridges.

Tolling Indiana’s six interstates – including I-64 and I-65 in Southern Indiana – would let the state “focus on the portion of the highway systems that is the most heavily travelled and the most expensive to maintain,” Omaha, Neb.-based HDR Inc., concluded in its feasibility study of a statewide tolling program.

Under the most optimistic projections, the study predicts tolls could produce $53 billion by 2050.

But coupled with fuel taxes and other surcharges, tolls would be a “double tax, if not a triple tax” on truck drivers, said Michael Deaton, a Corydon, Ind., truck driver.

Heavy trucks would pay the bulk of tolls on the interstates, according to the study.

“It’s just ridiculous to even consider it,” he said. “Those highways have been paid for for a long time.”

State lawmakers required the Indiana Department of Transportation to commission the work under a bill approved earlier this year that also raised the gas tax by 10 cents per gallon. The goal is to raise $1.2 billion a year for roadwork over the next two decades.

HDR does not make a recommendation in its October 31 study. Instead, the study now goes to Gov. Eric Holcomb to create a tolling plan by December 1, 2018 if he decides to pursue interstate tolls.

A Holcomb spokeswoman did not immediately respond to a request for comment Friday afternoon.

HDR assumes interstate tolls in Indiana would be charged without drivers having to slow or stop at tollbooths. Indiana and Kentucky state governments oversee a similar high-speed toll network on three bridges between Clark County, Ind., and Louisville.

That system, called RiverLink, uses cameras and antennae near the bridges to track license plates or scan transponders mounted on vehicles' windshields. Drivers without toll accounts – linked to a transponder or a license plate – will be billed by mail.

In the Louisville area, drivers of two-axle passenger vehicles now pay $2 to $4 to cross one of the RiverLink bridges: the I-65 Lincoln and Kennedy spans, and the Lewis and Clark Bridge that connects the Gene Snyder Freeway near Prospect with Indiana 265 in eastern Clark County, Ind.

The toll rates increase for vehicles with more axles and heavier trucks, climbing to $12 for tractor trailers without a registered RiverLink transponder.

In its study, HDR suggested toll rates that balance “revenue and mobility.”

Those rates included per mile tolls of 4 cents for passenger cars, 6 cents for medium trucks and 19 cents for heavy trucks on I-65, as well as on I-69, I-70, I-74 and I-94. The per-mile tolls would be higher on I-64, starting at 6 cents for cars, 25 cents for medium trucks and 63 cents for heavy trucks.

Under those assumptions, a family driving a sedan from Louisville to Indianapolis on I-65 would pay roughly $9 for a trip there and back. It would cost that same family roughly $15 to cross Indiana on I-64 driving from Louisville to St. Louis and back, for example.

Like RiverLink, drivers without a transponder linked to an account would pay more -- $2 to cover the cost of collecting the tolls.

Under the 2017 law, Holcomb must decide whether tolls are the “best means” of making “major interstate system improvements in Indiana.”

Fuel taxes long have been the main source of money for interstate construction and maintenance, but a generation of vehicles that run more efficiently has policymakers questioning whether that method is sustainable.

Tolls are generally prohibited on interstate highways, but HDR says Indiana is exploring whether it qualifies under one or more federal programs that allow tolls under limited circumstances, such as on new lanes added to existing roads.

The HDR report also concluded:

  • There is an 85 percent chance toll revenue would exceed $39 billion through from 2021 to 2050
  • Heavy trucks would pay the bulk of tolls under all of the scenarios, including 86 percent of the tolls paid on I-64 between New Albany, Ind., and the Illinois state line
  • Tolls would result in less traffic on the interstates by 2050, including 22 percent fewer vehicles on I-64 in southern Indiana and a 10 percent reduction on I-65 north of Indianapolis
  • Roughly 370 toll gantries, each costing $1 million, would be needed for a statewide tolling program

Reach reporter Marcus Green at 502-585-0825, mgreen@wdrb.com, on Twitter or on Facebook. Copyright 2017 WDRB News. All rights reserved.