WHEN VIRGINIA lawmakers enacted a major increase in the state’s subsidy for Metro two years ago, to match identical bumps from Maryland and the District, they did it mainly by raiding funding for other transportation projects in Northern Virginia. That move, engineered by Republicans who then controlled the state legislature, crystallized the state’s long-standing tradition of shortchanging vital infrastructure with stopgaps and financial legerdemain.

Gov. Ralph Northam, a Democrat leveraging the advantage of a new Democratic majority in both houses of the General Assembly in Richmond, has undertaken a bold strategy to revise that approach. Bold, that is, for Virginia, which despite a burgeoning economy and some of the worst traffic on the East Coast, retains a gas tax unchanged since Ronald Reagan was president.

The result is that drivers in Virginia, including those from out of state, pay less in taxes to fill up their tanks than they would in neighboring Maryland and North Carolina — and nowhere near enough to cover the cost of maintaining and repairing the roads they use. Mr. Northam’s proposal is to raise the state’s current gas tax, which is among the lowest in the nation, by roughly 75 percent over the coming three years, which (if gas prices hold steady) would add two or three dollars to an average fill-up. After that, he would index the tax to inflation, a measure that should have been enacted years ago.

Virginia is late to the game. Many other states have adopted similar strategies to help offset the steady decline in gas tax revenues, which have been sapped by increasingly fuel-efficient cars and the rising popularity of electric vehicles. Mr. Northam’s blueprint follows that model and adds a forward-thinking twist: He proposes that a sizable chunk of the new gas tax revenue, which would amount to nearly $500 million annually after three years, be devoted to enhancing passenger rail and transit.

That is in keeping with the state’s $3.7 billion agreement late last year to buy hundreds of miles of right-of-way for passenger trains from CSX and build a new rail bridge over the Potomac River, enabling Amtrak to double the number of trains it runs through the state and expand commuter service beyond rush hour in and out of the nation’s capital on Virginia Railway Express.

Mr. Northam’s transportation plan, like that of his Republican counterpart in Maryland, Gov. Larry Hogan, is all-of-the-above. Drivers want and need more funding for roads, without which congestion will worsen. At the same time, it’s smart policy to encourage commuters to consider switching to rail and transit — not by punishing them with crumbling, overcrowded and unimproved roads (as some Democrats in Maryland prefer) but by making other options more attractive.

The last time Virginia raised its per-gallon excise tax on gas was in 1986. It took more than a quarter-century after that for elected officials to raise new funds to bail out the state’s beleaguered roads, mainly through a sales tax increase in 2013. Now, seven years later, Mr. Northam has acted before a new emergency forces his hand. That looks like an improvement.

Read more: