“This is going to be more the norm than the exception in the future,” said Robert Puentes, the chief executive of the Eno Center for Transportation, a nonpartisan think tank in Washington.

Mr. Puentes said other cities should study Metro’s approach for how to balance rider safety, reliable service and transparency while operating in an unforgiving financial circumstances.

Metro’s particular woes are the product of years of neglected maintenance, poor management and oversight and uncertain finances. The system is younger than Boston’s or New York’s — the Red Line opened in 1976 — and its leaders spent much of their time and money on expanding it deeper into Maryland and Virginia rather than maintaining what was already built.

That began to change in the past decade after a series of accidents resulted in gruesome deaths and injuries that federal investigators traced to avoidable safety lapses. After a tunnel fire in March 2016, Metro’s general manager, Paul J. Wiedefeld, on the job only a few months, shut the system for a daylong emergency inspection. He eventually settled on the SafeTrack program as the best way to fix the worst parts of the system. The program compressed three years of work into a single, painful one. Sections of the system’s six lines were shut down or severely delayed for weeks.

The costs have been high. Rail ridership was down 10 percent through March compared to the last fiscal year. And ridership is down close to 20 percent, about 150,000 trips per weekday on average, since it peaked a decade ago.

Mr. Wiedefeld said it was clear to him that Metro’s long-held practice of skimping on maintenance to fund operations had put the whole operation at risk.

“That has to come to an end,” he said in an interview. “You could get away with it when you were a 20-, 25-year-old system. Going into your 40s and 50s, you can’t do that anymore.”