A Metrorail train waits in a D.C. station. (J. Scott Applewhite/ASSOCIATED PRESS)

VIRGINIA AND MARYLAND lawmakers are gathering for their annual legislative sessions almost exactly three years from the date of Metro's most recent calamity — the tunnel smoke incident at L'Enfant Plaza that sickened scores of passengers and killed one in 2015. That grim anniversary should serve as a warning in Annapolis and Richmond, and a reminder, of the unacceptable consequences of decades spent ignoring Metro's anemic finances.

This is the year legislators must stop shirking their basic responsibilities and find a way to shore up America's second-busiest transit network, the nation's only major system that lacks a reliable, ongoing, earmarked source of local funding. No more delays. No more pleading poverty. No more yes-buts. No more poison pills. No more After-You-Alphonse routines.

There are no perfect plans and no painless compromises. Some politicians in Richmond may gag over new taxes, even if they are modest, apply only in Northern Virginia and soak visitors (in the form of taxes on hotel stays), as then-Gov. Terry McAuliffe (D) proposed. Some in Maryland may wish to postpone the whole question, seeing nothing but pain in tackling it during an election year. Among politicians of both parties, there is talk that more money cannot be enacted without meaningful reforms — as if the hundreds of layoffs, massive maintenance surge and management overhaul over the past two years never happened.

The temptation to kick the can for another year will be powerful. It would also be calamitous. Metro's capital deficits are in the here and now, not pending in some gauzy future. The system requires a bare minimum of $500 million annually in new, earmarked regional funding for long-term projects, as well as continued federal and regional investment at the current level of $300 million annually, to pay for safety and maintenance upgrades.

In the absence of the additional funding, Metro managers, determined to protect safety standards, would be forced to raid current operating funds. Translation: steep fare hikes and service cuts for a system that has already lost nearly a fifth of its rail riders since 2012. That's a perfect storm, and a recipe for a death spiral. Having already been slapped with a fare increase last year, plus service reductions that have shortened operating hours and increased waits for trains, Metro's remaining customers will not readily tolerate more pain. More would bolt, further starving the system of revenue and undercutting the Washington region's most essential infrastructure pillar.

There are signs of hope. Maryland Gov. Larry Hogan (R) has signaled that he may allow a shift in state transportation funds in Metro's favor. Democrats in Richmond, heartened by a 16-seat pickup in the 100-seat House of Delegates in November's elections, are hopeful that their new clout will pay off in a revenue bill to address Metro's needs. In the District, too, desperate officials are champing at the bit.

Each is waiting for the other to act; all three jurisdictions need to pony up to generate adequate funds and make the deal stick. The stakes are too high for failure.