The first increase in Tennessee's gas tax in decades is about to take effect at the pumps.

Gov. Bill Haslam signed the Improve Act in April, increasing the tax on regular gasoline in Tennessee by 6 cents and diesel fuel by 10 cents incrementally over the next three years.

It’s part of a plan to work on a multi-billion dollar backlog of road projects. On Saturday, the tax on a gallon of gas will go up by a total of 4 cents. It will rise another 1 cent in each of the next two years.

The Shell gas station at the Emory Road exit off Interstate 75 sees a steady stream of drivers who stop to fill up their tanks, said store manager Laquisha Thompson.

“Easy access on and off the interstate, it helps a lot of people,” said Thompson. “One minute the parking lot could be completely empty, the next minute you turn around and it’s completely full.”

In the middle of the summer travel months, the volume will only go up.

"This is considered our Christmas season, so we expect to bring in more money and see more cars,” Thompson said.

It’s a scene she doesn't expect to change on Saturday, and even though it's been decades since the last increase, it isn't a complex adjustment for store owners.

"I just go on my computer, change the prices, hit okay, there we go - it's downloaded to the pumps. Probably takes 5 minutes,” Thompson said.

Gas is a necessity for drivers, so Thompson isn't worried about losing customers, it's more important to keep an eye on the competition.

"It depends on the season, time, holiday; people jack it up when they are slower for business, lower it when they will get a little more,” she said.

In the end, she believes the price at the pump is no competition to leaving her customers with a good impression.

"Friendly faces, smiles, a good clean environment, that's the best thing you can do at any gas station regardless of gas prices,” Thompson said.

The revenue from the gas tax will go to creating and fixing our infrastructure.

TDOT says there are more than 900 road projects in their backlog spread out across all 95 Tennessee counties. You can view the state's 2018-2020 Transportation Improvement Plan here.