LOUISVILLE, Ky. (WDRB) – A bigger chunk of toll revenue from three Louisville-area bridges will go uncollected in the coming years than previously thought, according to new estimates.

But after drivers get used to tolls, a consultant hired by Kentucky predicts a rosier outlook for traffic growth in the decades to come and more money from the fees as a result.

Boston-based Steer Davies Gleave made the updated projections in a June 25 memo to the Kentucky Transportation Cabinet and posted online Thursday morning. The estimates take into account new toll rates and national economic forecasts, among other factors, the memo says.

The toll rates for the RiverLink network, which are based on size and axles, were approved last month. They pushed more vehicles into a classification that will charge $5 to $7 per crossing, meaning fewer large trucks will pay $10 to $12, according to the memo.

Tolls are set to begin by the end of the year on the Interstate 65 Kennedy and Lincoln bridges and a yet-to-be-named span between Prospect, Ky., and Utica, Ind.

The more optimistic projections rely on research by Moody’s Analytics that anticipates higher job growth in the 12-county Louisville metro area and an increase in vehicles crossing the river. Moody’s credit rating division has given Kentucky’s debt on the project the lowest of its investment-grade ratings.

In all, tolls are expected to bring in $8.23 billion from 2017 until 2058, compared with earlier estimates of $7.96 billion. The overall construction and development cost of the Ohio River Bridges Project is $2.3 billion.

Toll rates vary depending on whether a driver has a windshield-mounted transponder, an account linked to a license plate or no account at all.

Cameras and other equipment near the bridges will record license plates or scan transponders on vehicles' windshields. Drivers without toll accounts -- linked either to the transponder or a license plate – will get a bill in the mail.

Consultants predict two percent of transponder revenue will go uncollected during  the life of project. The “leakage” rate for tolls assessed using the cameras will be higher – 15 percent won't be collected in 2017 and 2018, falling to 10 percent in 2019 and 2021 and leveling off at five percent after that.

The memo updates a 2013 study that was conducted prior to Kentucky’s sale of $728 million in bonds and other debt for its portion of the bridges project.

Kentucky Transportation Secretary Greg Thomas said in a news release that it was “prudent” to update the earlier work.

“We’ve learned a lot and we’ve made a lot of decisions since the 2013 study, including finalizing the vehicle classification system,” he said. “We wanted a system that is clear, easy to understand and meets the financial obligations of the project. This updated study tells us we’re right on track.”

While anticipating that traffic using all five Ohio River bridges will climb at slightly higher rates than first forecast, the memo doesn’t address how many vehicles are expected to use the three toll bridges.

The I-64 Sherman Minton and Clark Memorial bridges won’t be tolled. In its 2013 report, Steer Davies Gleave anticipated that drivers will look to avoid tolls on the I-65 corridor by using the two spans without tolls.

It projected that daily traffic on the Sherman Minton will climb to nearly 121,000 by 2030 – up from 78,160 in 2012 – while the tolled I-65 bridges actually would have 29 percent less traffic than in 2012.  The Clark Memorial also would see a spike in vehicles.

The report released Thursday provides a glimpse into driving trends during construction of the new bridges. It found that from 2012 to early 2016, traffic increased by about 4 percent on all bridges between Louisville and Southern Indiana.

Traffic fell on the I-65 corridor by about five percent while climbing by 12 percent on the Sherman Minton, which carried 87,500 vehicles a day. The steepest increase was on the Clark Memorial – from 24,100 trucks and cars each day in 2012 to 30,600.

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