Washington’s Metro system resumed rail service early Thursday after an emergency one-day shutdown that caused disruption and anxiety in the region.

Metro General Manager Paul J. Wiedefeld said that inspectors had identified 26 areas where electrical cables or the boots that connect them to the third rails were damaged or frayed, and that with some of the system still to be inspected overnight, the number could rise.

He called three of the problems — near the McPherson Square, Foggy Bottom and Potomac Avenue stations in the heart of downtown Washington — “show stoppers” that would have caused a shutdown of train service in those areas if discovered in the course of routine inspections. Although they would not necessarily have caused a fire, he said, they needed immediate repair.

“The shutdown today was necessary,” he said. But he acknowledged that “today presented a hardship for the region.”

Meeting with reporters, Wiedefeld showed a video of one exposed jumper cable that looked like a jumble of wires, its insulation peeled away.

Safety checks during Washington region’s rail system's 24-hour shutdown revealed severe cable damage in three sections. (YouTube/MetroFoward)

As of 9:45 p.m. Wednesday, Metro had finished inspections and repair work on the Red, Yellow and Green lines, and Metro spokesman Dan Stessel said the three lines will operate normally starting at 5 a.m. Thursday. Inspections on the Orange, Blue and Silver lines were expected to continue into the early morning hours, he said, and it was not clear whether single-tracking will be necessary on any of those lines.

Riders were relieved that the system would reopen Thursday. “I hope everything is straight,” said Bruce Milles, 28, who sat at a busy I Street stop, waiting for a bus home. His commute Wednesday was too difficult, he said. It took three buses to get from his Brookland home in Northeast Washington to the Pentagon City restaurant where he works. “Thank God they are opening,” he said.

The emphasis on safety would continue. The Transportation Department announced Wednesday that it plans to launch a safety inspection blitz of the Metro rail system, beginning next week, to review red-light running by train operators, imperfections in tracks and misuse of hand brakes.

Transportation Secretary Anthony Foxx said the Federal Transit Administration (FTA) would redirect hundreds of millions of dollars in money unspent by Metro to address safety concerns.

The unprecedented one-day shutdown of the 100-mile rail system, on which passengers take 712,800 trips on an average weekday, came two days after a “jumper cable” electrical fire that was eerily reminiscent of one last year that resulted in one death and sent scores more to the hospital.

The region lurched through the first day since 1976 in which Metro was shut down for something other than a blizzard or hurricane. Unlike those rare instances, the federal government, schools and offices were open for business. But much has changed in 40 years, perhaps foremost among them the ability to telecommute rather than journey to a workplace. Thousands of people did just that.

During both morning and evening rush hours, traffic was not much heavier than usual for a Wednesday, and some drivers found it lighter than average. Some buses were more crowded than usual at peak hours, but riders reported that there often were seats or room to crowd in.

Bicycles were out in numbers on a pleasant spring day, and some riders said that they had dusted them off after a winter in the basement. More than twice as many bicyclists and pedestrians as normal crossed the Key Bridge between Rosslyn and Georgetown on Wednesday morning, numbers from Arlington County’s automated counters showed.

Traffic experts said it would be days before clear conclusions can be drawn about how badly — or gently — the absence of Metro hit the region.

The evening rush in central Washington had swaths of misery, as ever, with some places hit harder than usual and others sputtering along as they do daily.

“We have a couple that are normal, we have a couple that are a little heavier than normal, and we have a couple that are lighter than normal,” said District police spokesman Lt. Sean Conboy.

Metro management and the leadership of the three jurisdictions the system serves — the District, Maryland and Virginia — came under attack on Capitol Hill on Wednesday as the Senate Appropriations Committee considered a transportation bill.

[Tracking Metro’s biggest meltdowns]

The hearing brought together Foxx and Sen. Barbara Mikulski (D-Md.), who took turns lambasting the failings that led to the shutdown of the system.

“It was drastic. It was disruptive. And yet I believe it was necessary,” Mikulski said. “We have called for years now for a culture of safety, but what we get is a culture of resistance to making changes for safety.”

Mikulski ran through a litany of steps that had been taken to revive the Metro system without appreciable success.

“My constituents and those in the District of Columbia and Virginia say, ‘Well, we’ll tough it out for one day, but is this change going to be reliable, is it going to be sustainable, is it going to stick?’ ” she told Foxx.

Foxx agreed that “the culture down there has to change.”

He reiterated his frustration over the failure of the region’s leaders to create a new safety oversight body for Metro. The FTA took over that function last year after concluding that the current body — the Tri-State Oversight Committee — was a failure.

The three jurisdictions have agreed to set up a more powerful body, to be called the Metro Safety Commission. But that process has been delayed by as much as a year because neither Virginia nor Maryland moved to obtain necessary approval from their legislatures this year.

Foxx said that Metro had received hundreds of millions of dollars in federal funding for various purposes over the years that remained unspent. He said the FTA was scrutinizing that money with the intent to instruct the Washington Metropolitan Area Transit Authority to divert the money to address safety concerns.

“We have the authority to direct that they use those monies to focus on their safety priorities,” Foxx said. “Rest assured that we’re going to make sure that resources are not the issue. But I think that the point is that I don’t think it is just resources. I think it is culture and I think it is a deliberate decision that is needed from everyone involved in this to focus relentlessly on safety.”

[Metro delays caused by cable problem similar to last year’s fatal smoke incident]

Experiencing a commute in the D.C. region without a working Metro system revealed two drastically different experiences, much of it depending on what people did for a living and, to some extent, how much money they make.

That’s why, experts said, many drivers, particularly on roads leading into the city from some suburbs and beyond, actually found noticeably lighter traffic than usual while some bus riders spent several hours navigating routes that were so jammed that buses occasionally couldn’t pick up new passengers.

“It shows the economic divide that exists in every city,” said Tom Murphy, a senior fellow at the Urban Land Institute who was mayor of Pittsburgh from 1994 to 2006.

The many workers — most likely in white-collar jobs — who could have driven but had the option of working from home and did so, freed up space on the roads. Meanwhile, many workers in lower-wage service jobs, particularly those who can’t afford a car or did not have the option of telecommuting, were left packed on buses.

Murphy said he noticed that Rock Creek Parkway in Northwest Washington had significantly lighter traffic than usual: “It was almost like a holiday,” he said.

But he also heard stories of people jammed on buses in other parts of the city.

“I was shocked at how little traffic there was,” said Murphy, a frequent Metro rider who was able to walk to work Wednesday.

But many people, he noted, had no other option but to find a way to get to work.

“People who work in restaurants need to be there,” Murphy said. “There’s no way to telecommute as a waiter or waitress. I think people don’t always remember that for an important part of the population, transit is their means of movement, and they don’t have other options.”

Murphy noted that half of his office worked from home Wednesday, while the building’s maintenance worker, who usually takes Metro, rode his bike 2 1/ 2 hours to get to work.

“These are people who are making sure the elevators run and the food is cooked and served in restaurants,” Murphy said. “It’s a whole infrastructure that makes everything else work in Washington, and a very big percentage of those people depend on transit.”

One of them was Kuing Hu, who stepped off the 26 bus and walked into the Largo Town Center Metro station Wednesday. She saw it was deserted and realized that something was amiss.

“Oh, my God,” she muttered.

A station official stepped out to explain that the system was closed and offered alternatives. Hu had not watched the television news or noticed messages on her commute home Tuesday.

“If I need to pay more money, I cannot go to work,” Hu responded when presented with options for multiple bus transfers or hailing a cab. “It’s just today?”