As the Virginia General Assembly grapples with competing transportation plans, one thing is certain. In just four years, road maintenance will consume virtually all available highway revenue as required by state law, leaving no money for new road construction.

It doesn't make sense to build new roads while existing thoroughfares turn into pothole-pocked obstacle courses, but the maintenance "crossover" has consumed more than $3.3 billion since 2002, even as the state budget increased 66 percent. The failure of previous governors and legislators to allocate sufficient funding for both maintenance and new road construction is the root of the current crisis. Gov. Bob McDonnell deserves credit for tackling this intractable problem instead of leaving the mess to his successor.

His solution, approved by the House of Delegates, is to raise $3.1 billion over five years by completely eliminating Virginia's 17.5-cent gas tax and replacing it with an 0.8 percentage-point increase in the state sales tax. This is a good but not perfect solution. It is opposed by liberal Democrats and conservative Republicans for totally different reasons. But at least it gives nondrivers -- who benefit from well-maintained roads just as much as nonparents benefit from good schools -- some skin in the game.

The state Senate passed a measure allowing local jurisdictions to impose their own income tax (a power they already have) for transportation by eliminating the current requirement for a public referendum to protect taxpayers. This is not a good idea.

Then there's the "friendly amendment" to the governor's proposal offered by the Springfield-based Thomas Jefferson Institute, which focuses only on the "festering problem" of road maintenance, leaving the issue of new construction to the next governor and legislature. Instead of totally eliminating the gas tax, TJI would raise it 20 percent, off-setting the 3.5-cent-per-gallon tax hike by indexing state income tax brackets to inflation.

TJI President Mike Thompson explained that economic modeling by the Beacon Hill Institute in Boston shows that this would increase employment four times more than the governor's plan (14,950 vs. 3700 jobs) while increasing Virginians' disposable income $1.8 billion over five years. Even so, with national gas prices reaching historic highs, this will be a hard sell politically.

Both of these revenue-neutral proposals have their flaws but both ultimately allocate a larger share of state revenue to transportation, which a good thing. And Virginia can no longer afford to sacrifice a good solution for a perfect one that never arrives.