You get what you pay for

by Rebekah Bovenmyer

You might not realize it, but every time you fill up your gas tank, you're paying for the roads you drive on. The federal government currently gets $0.18 from the price of each gallon to pay for highways and interstates.

Your state collects up to $0.30 from the cost of each gallon of gas to pay for road construction and maintenance. Vehicle registration fees and property taxes are also used to pay for city streets and state and county highways.

It's supposed to work as a user fee. The more you drive, the more gas you use, the more tax you pay for the roads. The gas tax is a behind-the-scenes way of doing what toll booths do up front: charge you for using the road.

How much does that add up to? The average person drives 12,000 miles each year and gets 20 miles per gallon. If the federal tax is $0.18 per gallon, then each person would pay about $108 each year for roads.

If the state tax is $0.30 per gallon, then that means a person spends about $180 each year for state roads.

But is that enough to fix the roads we already have, much less pay for new ones?

Why it won't work forever

The fees collected for roads aren't cutting it. Roads and bridges need repairing, but there's not enough money to fix and rebuild what needs it. The Iowa Department of Transportation (Iowa DOT) estimates a $4 billion shortfall to meet the most urgent needs over the next 20 years.

"Something has to change. Revenues haven't grown like they used to because of hybrids, alternative fuels, and miles per gallon increases. We just see that continuing," says Stuart Anderson, director of the Office of Systems Planning at the Iowa DOT.

Cars are becoming more efficient. They can go farther on less gas, so drivers aren't filling up as often as they used to. Congress recently increased the minimum miles per gallon for new cars from 25 to 35 by 2020.

Gas isn't the only fuel cars are running on anymore. Vehicles are starting to run on electricity or a combination of electricity and gasoline, called hybrid cars. New engine systems that run on hydrogen fuel cells don't use gasoline at all. This new technology is good for the environment but bad for collecting tax money for our roads.

Paying by the mile

If the real purpose of the tax is to charge people based on how much they use the roads, then why not do just that?

Researchers on 2 separate projects are investigating a road user fee based on miles driven. The University of Iowa Public Policy Center and the Oregon Department of Transportation are both looking for a different way to charge drivers for using the roads.

Here's how:

A global positioning systems (GPS) receiver is added to a car. This receiver communicates with a GPS satellite to figure out what kind of road the car is driving on. (There could be different charges for city, state, and federal roads, or during rush hour.)

In the Oregon study, the satellite only checked for which zone the car was in: in state, out of state, city during rush hour, or "no signal" if the car was in a tunnel or parking garage.

A computer in the car continually checks the odometer and stores the number of miles traveled in each zone.

In the Oregon study, special equipment was added to 2 gas stations in the state. When a person with the study's GPS equipment filled up the tank, the usual gasoline tax was automatically deducted from her bill, but the mileage charge was added. The driver paid the bill at the gas station just like she normally would.

Rather than paying at the pump, drivers in the University of Iowa study will have a separate bill sent to them with their mileage fee when the field test starts this year.

No one's sure how much the mileage fee would be for using the roads. If it's going to make a difference in the road budget, most likely it will be more than what we're paying now in the gas tax.

"Big brother"

You might know how annoying it can be to have a brother or sister follow you around and tell your parents about your every single move. Some people worry that paying by the mile will allow the state or federal government to track people as they drive and violate their privacy.

Both the Oregon and the University of Iowa studies have been concerned about drivers' privacy. The computer in the car only saves the total number of miles driven in each zone or on each type of road. It doesn't keep a record of the date and time, so no one could look through the records and find out where a driver was. The Oregon study didn't track which road drivers were on at all—just what zone they were in.

Plus, the GPS and on-board computer systems have been set up to only upload the miles at certain times—at the gas pump or once a month to a billing center. There isn't a real-time connection to the vehicle that would show a government agency exactly where a car is.

Until someone invents the personal transporter, our country's roads and bridges need to be continually maintained and upgraded. Cars are becoming more efficient and using less gas. Eventually, vehicles might not run on gas at all. So, charging drivers a small fee per mile makes more sense than keeping the tax tied to the amount of gas we put in our cars.