Governor Bill Haslam's proposed gas tax hike is getting some pushback.

The plan, which is part of the IMPROVE Act he revealed last week, also includes lowering the grocery tax from 5 percent to 4.5 percent and, over the course of two years, decreasing the Hall income tax by 3 percent.

RELATED: Haslam plan calls for 7-cent gas tax hike, cuts to grocery sales tax

Haslam's plan would raise the tax on regular gas by 7 cents a gallon and 12 cents on diesel. The governor estimates it would cost the average Tennessee driver an extra $4 per month.

All of this, he said, would bring $278 million in new dollars to TDOT, to help fund its road improvements wish list, which is 962-projects-long across all 95 counties, totaling more than $10.5 billion.

RELATED: Gas tax hike would fund Chapman Highway repairs

However, some lawmakers want a different solution.

"Do we have a need in infrastructure? Absolutely," Republican Knoxville Rep. Jason Zachary told WBIR 10News on Monday. "I sit on the transportation committee and there are things that we can do."

Zachary filed a bill last week which he calls an "outside the box" solution to TDOT's backlog. This alternative plan to Haslam's IMPROVE Act funds TDOT's priority projects while avoiding a gas tax hike.

Instead, his plan utilizes the state's current budget surplus.

"When you get to a point that you're going to have to raise taxes and I'm telling the people I represent that we have these billions of dollars in surplus and I'm going to have to raise your taxes, they push back on me and say, 'Find another way,'" Zachary said.

Surplus money, traditionally, has gone to the state's General Fund. In Zachary's bill, however, 25 percent of any monthly surplus over $5 million would go, instead, to TDOT.

"Every month, we designate $20 million, $10 million, $11 million. At the end of that year, that money is designated for TDOT," he said.

Rep. Zachary tried passing this bill last year, but it died in committee. If his bill had passed in 2016, for example, TDOT would have received a total of $200 million from the current surplus, Zachary said.

The bill he filed last week is the most advanced, workshopped form of last session's bill. At the heart it is finding an alternative to raising the gas tax when the state has a significant surplus, even though Haslam said the average driver would incur an increase of just $4 per month.

"I've had a truck driver email me, that told me that he never leaves East Tennessee," Zachary said. "If they raise the diesel tax to what they're talking about raising it to, it'd cost him $250 to $300 more per year."

Read Zachary's bill HERE and track its progress HERE.

Rep. Eddie Smith, a Knoxville Republican, also sits on the transportation committee.

Regarding Zachary's bill, Smith said it does not specifically funnel any road funds to cities or counties. Haslam's plan, on the other hand, does. Smith said he likes that the governor's IMPROVE Act would, for example, provide Knoxville with nearly $2 million more per year than the city is currently getting for road improvement projects.

Smith is also wary of Zachary's bill's monthly surplus provision.

"I think that there's merit to it, but I believe we have to be careful of how we do it to make sure we don't put ourselves in a financial pinch, month-over-month," Smith said.

He, like Zachary, has heard from constituents about Haslam's proposal.

"There are some that are just adamantly opposed to it," Smith told 10News. "There are some that are like, you know, they believe it's a good first step, they believe that we can do some more protections."

Read specifics of Haslam's proposal HERE.

He said he wants to remind people that with a gas tax hike comes cuts elsewhere.

"What the governor has proposed, as I've read it, is a reduction in the general fund tax collections and an increase in the road fund," Smith said, "so we're not asking for any more money from Tennesseans. We're just going to collect it differently."

However, he said, he has not yet come out in support of Haslam's plan.

"I'm still looking at it," Smith said. "As I've told several people, the devil's in the details, and while we've seen the proposal, we have not seen the bill."

He said he'd likely want the bill amended before voting for it.

For example, he said, "if the federal government comes behind us and decides to raise the federal fuel tax, we need an automatic trigger in whatever we do that would lower the taxes for Tennesseans because what we, in effect, are saying is, 'This is the amount of money that we need to do road projects in the state. We don't need more.'"

Smith said he's heard of a number of other lawmakers considering alternatives to Haslam's IMPROVE Act.

Both representatives said they're concerned about the portion of the IMPROVE Act that ties future state gas tax increases to the Consumer Price Index, to keep up with the rate of inflation.

"We're talking about an automatic increase on taxes without being voted on by the General Assembly every single time," Smith said.

"The tax increase would be on autopilot...Us as legislators would lose control of saying, 'We want to raise it to here,' or, 'We want to decrease it to here,'" Zachary said. "That I have a real problem with, because that's our job as legislators representing you."

Both Smith and Zachary said they encourage constituents to contact their legislators with questions and opinons about this, as it's still so early in the process and lawmakers are looking for input from an informed public.

The session picks back up next Monday.