DENVER -- Colorado Governor John Hickenlooper is encouraging lawmakers to "think outside the box" when it comes to funding highway improvements.
Transportation was a big part of his State of the State message Thursday.
He said that over the next decade, Colorado will have $9-billion in unmet transportation needs.
"That need will only grow," he said, as more people move to Colorado.
CDOT communications director Amy Ford told Denver7, that Colorado barely has enough money to maintain existing roads.
"We have very little budget to add new capacity," she said. "When you drive on I-25 or I-70, you can tell that we haven't made significant improvements in a long, long time."
Ford said neither 22-cents a gallon state gas tax, nor the 18.4 cents a gallon federal gas tax have increased since the 90s.
She said population growth and more fuel-efficient cars are putting a strain on the existing system because people aren't paying as much as they were before.
Increasing the gas tax is one option. Sales tax is another.
"If you use your car on a daily basis and you're working, pay the extra tax," Larry Waitz said, while waiting in his car at a grocery store parking lot. "I don't want to see them double it, but a 20 percent increase would help fix our roads.
Driver Robert Teselle says increasing the gas tax seems the simple thing to do. When asked about a sales tax, he said, "I don't like that idea.".
When asked why, he said, "I don't know. It just doesn't have anything to do with roads."
Teselle's brother, William, also told Denver7 that raising the gas tax would make the most sense, since it would be making people pay for what they use.
"Whichever has the least impact on my bottom line would be the best scenario," he said.
Road Usage Charge pilot project
Ford said CDOT is also looking into the feasibility of a road usage charge.
She said a pilot project, involving 100 volunteers, began earlier this year.
Each participant is keeping track of their mileage in one of three ways.
"We do a low-tech way, where you just take a picture of your odometer," Ford said. "You can do a higher-tech way where you plug something into your car and it tracks you, but not on a GPS system, just counts those miles."
Ford said there's even a higher-tech way "where it knows where you're going, so it can determine whether you're on a private road or a state road, and allocate payments that way."
She said CDOT expects to have results from the pilot project sometime in the spring.
"It'll tell us how well it works, what the impact is between rural vs. urban and whether Prius owners now have to pay a little bit more and how it impacts me, if I drive a Ford F-150."
Ford added that a road usage charge, if ever approved, is a long range option.
She said lawmakers will have to come up with a different solution for the short term.