By Andrea Flores

DENVER (CBS4) – Colorado’s gas tax has been used to fund state infrastructure for decades, but Colorado Department of Transportation is working on a pilot program aimed at finding alternatives.

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Like many Colorado commuters, Maggie Bolden spends most of her spare time sitting in traffic.

Maggie Bolden drives. (credit: CBS)

“Today, it took me about 40 minutes to get to work,” she said when CBS4’s Andrea Flores interview her last month. “On average, for a month, I can drive anywhere between 500 to 600 miles.”

Bolden isn’t alone.

With a booming population, inflation, and a rise in fuel efficient vehicles over the years, CDOT is looking for a sustainable funding alternative to the decades-old gas tax.

(credit: CBS)

“It’s a research project that looks at the concept of a pay-per-mile philosophy,” said CDOT project manager, Tim Kirby.

More than 100 volunteers participated in the self-selected Road Usage Charge pilot project last year.

(credit: CBS)

Bolden was one of them.

“I think we can all agree that the roads are extremely bad, so how are we going to pay for that?” she said. “If the gas tax isn’t covering all that, what does it look like to cover the cost of improvement?”

Over the course of four months, Bolden was given the option to record the miles she drove or install a tracking device into her vehicle.

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Results show, on average, a majority of the more than 100 participants owed $10 or less per month in road usage charges, about $4.25 cheaper than the average of what they paid in gas taxes during the same period.

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CBS4’s Andrea Flores did the math on a 2016 AWD GMC Terrain. If she drives 400 miles a month, the proposed road usage charge comes out to nine cents less than what she currently pays at the pump.

(credit: CBS)

But many question whether the numbers are too good to be true.

The cost could differ depending on the year, make, and model of your vehicle. Bolden adds, no real money was used during the pilot.

“I’m not sure that I had a really good perspective about what I didn’t like about it since I wasn’t paying for anything,” she said.

Pilot survey results reveal participants worried about how the road usage charge would account for out-of-state drivers, and how it could affect low income and rural communities.

Survey numbers show 94 percent of participants were Caucasian, and more than half lived in the Denver metro.

(credit: CBS)

CDOT says they plan to include more diversity in future pilots.

“The main goal is to do the adequate research so if decision makers decide road usage charging is a road usage alternative that they would like to deep explore, they have all the information they need to have that conversation,” CDOT’s Kirby said.

This spring, CDOT is partnering with the Colorado Farm Bureau to look at how the road usage charge could work in rural areas.

CDOT encourages drivers to test it out and do the math for your vehicle.

LINK: CDOT’s Road Usage Charge Calculator 

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Andrea Flores is a reporter for CBS4. Follow her on Facebook and Twitter @AndreaFloresTV.