The idea is to make sure every user of the state’s roads helps pay for them, said Maureen Bock, manager of the Oregon Department of Transportation’s miles-based usage program, That means the owner of a new electric Tesla, who does not have to buy gas, pays the same as the owner of an old gas-guzzling pick-up truck. The amount of damage a vehicle does to the road is the same up to 10,000 pounds, so all vehicles in that weight category pay the same, said Bock.