Oregon is looking into whether gas taxes can be replaced by a per-mile road-use fee for all cars come July of this year.

With the evolution of cars and their new "greener" make-up, less money is required for fuel, but this hurts the funds stowed away for road maintenance in the U.S.

Cars that run solely on electricity are really affecting the revenue coming from gas taxes, so the state is trying to come up with another way to make money that doesn't involve placing a tax on electric cars - a method that's currently used by other states.

"Fuel efficiency is getting better and better, which is great," said Michelle Godfrey, an Oregon Department of Transportation spokeswoman. But "when your road maintenance is funded by fuel sales, that spells trouble."

Oregon will attempt to introduce the nation's first mileage-based road tax. A pilot program will be launched to test the success and it will include 5,000 volunteer drivers and the use of a data-gathering system, according to Automotive News.

Drivers have two options: pay the gas tax at the pump or pay 1.5 cents for each mile driven.

As part of the test, a device made by Intelligent Mechatronic Systems will be plugged into the onboard diagnostic port to keep track of miles traveled. Road-tolling company Sanef ITS Technologies America will analyze all recorded data.

For now, drivers will still pay the gas tax, but at the month's end, the data will be sent to the Oregon Department of Transportation, which oversees tax revenues, Auto News reported. The DOT will look at mileage data and then compare it with how much fuel was consumed. Test participants will get a rebate or a bill for any unpaid road taxes.

This isn't Oregon's first attempt at creating a mileage-based road tax. The state tested a program in 2012 and 2013 in which it had 88 participants, and based on that model, the state legislature approved a bill for the creation of a larger system.

Out-of-state drivers are not included in Oregon's system, which could raise concerns over privacy issues due to the mileage-tracking device being placed in the vehicle.