DOVER — Delaware could soon replace its gasoline tax with a mileage-based levy in which motorists would pay varying amounts depending on how many miles they drive.

The U.S. Department of Transportation said Tuesday that Delaware and four other states have been awarded $1.49 million in federal funds to study the impact of the new method of taxation to pay for infrastructure costs.

The grant, received by the states as part of the I-95 Corridor Coalition, requires them to test 50 vehicles to examine how replacing the state gasoline tax with a user fee — determined by an annual assessment in which motorists are charged based directly on how many miles they drive — would work.

“Finding sustainable revenue to replace stagnant fuel tax receipts is clearly a sensitive topic with the public,” Delaware Department of Transportation Secretary and I-95 Corridor Coalition Chairperson Jennifer Cohan said in a statement.

“That makes this project a fantastic opportunity to foster dialogue about how our transportation system is funded, the need for a reliable revenue source and how citizens benefit from the mobility our region provides.”

The state’s 2016 fiscal year budget included $456 million for road and construction projects.

Revenue for government from the gasoline tax has been declining as cars become more fuel-efficient and electric vehicles become an alternative.

Gov. Jack Markell, a Democrat, applauded the grant, saying in a statement he thinks investment in infrastructure helps create jobs.

U.S. Sen. Tom Carper, D-Del., cheered the tax on mileage concept.

“I always say if something is worth having, then it’s worth paying for, and the bottom line is that the people who use our roads and bridges should pay to maintain them,” he said in a statement.

“For too long, we’ve shirked our responsibility to adequately fund our country’s transportation system, instead opting to kick the can down the road so somebody else can clean up our budgetary mess,” he added. “It’s high time we explore more responsible ways to rebuild and maintain our roads, highways and bridges, and this federal grant makes an important investment in doing just that.”