PEMBROKE PINES, FL - NOVEMBER 15:  Gas pumps with a sign indicating the gas is containing up to 10 % ethanol are seen at Victory gas station on November 15, 2013 in Pembroke Pines, Florida. Today, the federal Environmental Protection Agency announced a proposal to ease an annual requirement for ethanol in gasoline.  (Photo by Joe Raedle/Getty Images)
Joe Raedle PEMBROKE PINES, FL - NOVEMBER 15: Gas pumps with a sign indicating the gas is containing up to 10 % ethanol are seen at Victory gas station on November 15, 2013 in Pembroke Pines, Florida. Today, the federal Environmental Protection Agency announced a proposal to ease an annual requirement for ethanol in gasoline. (Photo by Joe Raedle/Getty Images)

The federal gas tax has been 18.4 cents per gallon since 1993. That's not nearly enough to pay the average state's transportation infrastructure repair bill. In fact, estimates the American Society of Civil Engineers, the average annual funding gap is $94 billion.

With one highway bill extension under way and Congress dead set against increasing the federal tax, more and more states are taking matters into their own hands.

According to the Citizens for Tax Justice and the Institute on Taxation and Economic Policy, drivers in Idaho, Georgia, Maryland, Nebraska, Rhode Island, and Vermont will be charged more at the pump as a result of laws taking effect at the start states' new fiscal year.

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