Prius and Volt owners need to pay for roads too

Although fuel taxes encourage people to buy more fuel-efficient vehicles such as the Toyota Prius and Chevy Volt, these vehicles still use roads and cause road wear. But funding to repair roads comes from fuel taxes, and, as more people drive the Prius and Volt and other fuel-efficient cars, the revenue from fuel taxes can no longer cover required highway spending. A solution to this funding shortfall is to tax drivers per mile rather than per gallon.

The Highway Trust Fund, financed by federal fuel taxes set at 18.4 cents per gallon for gasoline and 24.4 cents per gallon for diesel in 1993, provides funding to repair and build federal highways. Since 2008, however, highway spending surpassed the revenues from the trust fund. To make up the shortfall, the Treasury has had to provide $30 billon to the trust fund.

As a way to address the shortfall, the Senate asked the Congressional Budget Office (CBO) to assess the feasibility of taxing people on how many miles they drive, rather than on how many gallons of fuel they consume. The CBO concluded that, with current technology, “electronic metering and billing are making per-mile charges a practical option.” A mileage tax is a better way to charge the actual users of the highway system.

Such a tax, however, should account not only for miles traveled but also for the weight of the vehicle. For example, one tractor-trailer causes road damage equivalent to 9600 cars. Although requiring tractor-trailers to pay their proportional share of the road damage would raise the cost of freight and the prices of goods, by not doing so compels automobile drivers to subsidize the trucking industry. A more equitable tax on heavy trucks would be fairer, and would even benefit local economies by making local products more competitive.

An alternate solution to taxing either fuel or mileage is to privatize roads and pay tolls, which would definitely ensure that users pay for the highways they drive on. Of course, that would put the transportation infrastructure – so essential to economic development – in the hands of unaccountable (and even offshore) corporations.

For the last 60 years, development was built around gas-powered automobiles, which fomented wasteful habits and suburban sprawl. Taxing miles driven would help ensure that the actual users, even Prius and Volt drivers, pay for highway improvements. Such as tax would also encourage smarter development and walkable communities. Any mileage tax however, should be tiered by vehicle weight so vehicles that cause the most road wear, such as tractor-trailers, pay their fair share.