Virginia Gov. Ralph Northam (D) in Richmond on March 10. (Steve Helber/AP)

ALONG WITH Maryland and the District, Virginia took a major step this year toward restoring Metro to a sustainable financial position — and, in the process, assuring the region’s long-term prosperity. By passing a measure to boost the state’s subsidy for the transit system by $154 million annually, lawmakers in Richmond, where the legislature is narrowly controlled by Republicans, recognized that halting Metro’s death spiral is not a gesture of charity; it’s a question of economic survival.

Still, the good news from the commonwealth was tempered by the fact that the funding formula approved by the General Assembly mainly would pay for the Metro bill by gouging funding for road and other transportation projects in Northern Virginia. Roughly two-thirds of the new dollars for the transit system would be diverted from existing transportation blueprints in the region; the rest would come from state funds, as well as a tax on wholesale gas that would add just 30 cents, at most, to the cost of a 15-gallon fill-up at the gas station.

That two-thirds chunk translates into a $100 million annual hit to local and regional transportation funding — an act of robbing Peter to pay Paul that would leave gridlocked intersections impassable, clogged commuter arteries a mess and bike lanes unbuilt. Panicked local officials, including some Republicans in Fairfax, Prince William, Loudoun and Arlington counties, as well as in Alexandria, warned that roads they’d hoped to improve in the next few years might now have to wait as long as a decade.

Gov. Ralph Northam (D) has offered amendments to the legislation that would modestly increase taxes on hotels and home sales, raising about $30 million for Metro and thereby limiting by the same amount the cuts to other transportation projects in the region. The governor’s proposals are balanced and sensible. The question is whether Republican lawmakers, who hold the narrowest possible majorities in the state Senate and House of Delegates, will go along with them.

They should. Much or most of the new revenue would be raised from out-of-towners — tourists and business travelers at hotels, whose $500 bill would go up by $5 under Mr. Northam’s plan. Under Mr. Northam’s proposal, meanwhile, the tax paid by the seller of a $700,000 home would increase by $350 , to $1,400.

Similar measures were considered during the legislature’s regular session, which ended last month, but rejected by GOP lawmakers. Downstate legislators were not much concerned about the fine print of the Metro bill; their constituents wouldn’t be affected. But most deferred to Del. Tim Hugo (R-Fairfax County), who is among the last GOP state lawmakers representing Northern Virginia and who refused to go along with the new taxes.

Now, local officials from Northern Virginia, including several prominent Republicans, are pressing for the legislature to back Mr. Northam’s amendments. Their position is simple and logical: Virginians must pay for the transportation they use. Refusing to do so means suffering the consequences.