For the second time in as many weeks, Metro Red Line riders were frustrated by exceedingly long commutes, with some people reporting Wednesday morning that their trips took two to three times as long as usual. It took crews three hours to restore service to normal.

About 7:15 a.m., when Metro sent an alert warning riders of delays and single-tracking between Dupont Circle and Van Ness stations. Metro said the problem was caused when a cable that carries radio communications between trains and the operations control center fell from the 22-foot-tall ceiling of the tunnel at Woodley Park. The incident was first reported to Metro officials by a passing train’s operator.

The dangling cable on the inbound tracks meant trains could not run safely through the area. The delays were especially bad because crews needed to use special equipment to reach the ceiling.

Metro spokesman Dan Stessel said that the cable was “at a height that can’t be easily reached by a standard ladder,” and that loose cables are not a frequent problem.

The cause of the incident is under investigation, he said. The cable was temporarily secured, and crews were expected to go back after the system closed Wednesday night to permanently fix it, Stessel said.

Although Metro said commuters could expect delays of 20 to 30 minutes, many Red Line riders said their waits were far worse.

Travis Chapman, a lawyer in downtown Washington, said his commute from Grosvenor to Gallery Place, which normally takes about an hour, turned into a three-hour nightmare. He didn’t see Metro’s first e-mail alert warning of the delays until he got to the station. He said Metro personnel at Grosvenor did not offer any information on how long delays might be.

Two packed trains from Shady Grove passed him. He decided to take the Red Line north to Twinbrook in hopes of squeezing onto a train. But even then, he said, it was standing-room only.

“People were trying their best to be nice, but the train was stopping and waiting at every station for five or 10 minutes,” Chapman said. Once the train got to Van Ness, it was off-loaded and passengers were given no explanation.

A six-car train came, but it was crammed and also had to be unloaded, he said. Seeing that it would be an additional 10 to 15 minutes before the next train and that there was a “huge line” for the bus and taxis outside the station, he walked to Woodley Park and caught a D.C. Circulator bus to Columbia Heights. From there, he took a Green Line train to Gallery Place.

He had left his North Bethesda home at 7:30 a.m.; it was 10:30 a.m. when he got to his office.

“It was a little insane,” Chapman said.

Aubrie Sell, who rides the Orange Line from Dunn Loring with a final destination of Union Station on the Red Line, described her Wednesday commute as “hellish.” After waiting at Metro Center for trains (none came), she got back on the Orange Line and rode to Eastern Market, where she ended up walking more than a mile in high heels to her job as a preschool teacher at a D.C. elementary school.

“I am tired of being late and being forced to pay for inferior service,” said Sell, adding that she spends $10 a day riding Metro. She said she builds an extra 10 minutes into her commute for minor Metro issues. When there is a problem, she said, she finds there is little information from Metro or its station managers, which she called “appalling.”

In its defense, Metro said that it sent seven alerts about Wednesday’s disruption. It also said the Red Line’s on-time performance — an internally generated measurement the transit agency uses for its trains — has improved this year over last. On-time performance is running between 90 and 93 percent in the first six months of this year compared with between 85 and 90 percent for the same period last year.

But Metro officials acknowledged that for riders, it might seem like things aren’t improving.

“You’re only as good as your last rush hour,” Stessel said. “If you were caught up in the Red Line delays this morning, then it was a very frustrating experience and we recognize that. We apologize to customers who were significantly delayed.”

Stessel said one of the major problems with the Metro rail system is that with only two tracks on each line, there is no way to avoid trains having to share a track if a problem occurs.

“When you single-track, you’re reducing the capacity of the railroad by 50 percent,” he said.

“There’s no way to replicate that capacity,” Stessel said. “Any time there is single-tracking on the Red Line in rush hour, the potential for crowding and delays is very real.”

For riders, Red Line problems have seemed particularly acute of late.

One day last week, Red Line riders experienced delays of up to one hour after hydraulic fluid leaked from a piece of track equipment, forcing trains to share a track between Judiciary Square and Rhode Island Avenue stations from 5 a.m. until almost 9 a.m.

The latest delays show the Red Line still needs major improvements, even as Metro has undertaken an aggressive, $5 billion capital rebuilding program that includes rehabbing the Red Line, which is the oldest line on the 37-year-old system and has roughly 150,000 rider trips on a weekday.

Metro officials agree, there is more work to be done.

“We’re halfway through the aggressive [rebuilding] campaign,” Stessel said. “Things are better, yes. Are they perfect? No.”