States are allotting a growing share of the funds they raise from gas taxes to debt service and spending unrelated to roads and bridges, making them more reliant on federal assistance to pay for new infrastructure. The shrinking pot of state cash is one reason why governors increasingly are in a panic over a congressional impasse about replenishing the federal Highway Trust Fund. The federal fund, too, is running out of money and will cut disbursements to states in August if Congress doesn’t intervene. Texas spends 25% of its fuel-tax revenue on education programs. Kansas has allocated some of its gas-tax revenue to pay for Medicaid and schools. Nationwide, making interest payments on debt used to fund existing infrastructure projects is one of the biggest state expenditures. Allen Biehler, who ran Pennsylvania’s transportation department for eight years before joining Carnegie Mellon University in 2011, said many states pursued bond […]