Train speeds are restricted on two of the four tracks on the Walk Bridge after work crews were able to close the span, Metro-North said.
Earlier in the afternoon, train traffic had been suspended between South Norwalk and East Norwalk while crews worked to close the bridge, a 118-year-old swing span that crosses the Norwalk River.
The first train moved eastbound at 6:20 p.m. at restricted speed of 15 mph.
Metro-North is warning customers to expect substantial residual delays after the service interruption.
4:30 p.m. story: NORWALK, Conn. -- Buses are running Friday to shuttle train riders around the malfunctioning Walk Bridge in South Norwalk that has stopped Metro-North train service through South Norwalk as of about 3:30 p.m. Friday, Metro-North said in a statement.
The MTA Bus Co. is providing 24 buses from the Bronx to shuttle Metro-North customers between South Norwalk and East Norwalk. Trains will run in two sections: Between Grand Central and South Norwalk, and between East Norwalk and New Haven.
Train service between Stamford and Grand Central is not impacted.
The bridge, which swings open to allow boating traffic to get through, became stuck open at about 3:30 p.m., disrupting train service at the start of the busy Friday afternoon rush hour, Metro-North said.
"This was a regular opening for marine traffic on the Norwalk River," a Metro-North spokesman said.
The 118-year-old bridge is stuck in the open position, the Metro-North spokesman confirmed, adding that the exact reason the bridge is stuck was unclear. It was stuck in the open position on May 29 for several hours after a routine check on the mechanics, disrupting the morning commute.
"Mechanics are unable to close the Walk Bridge near South Norwalk and repair crews are on site working to resolve this issue," Metro-North said in a statement.
Several crews are at the site working on resolving the issue, including the overhead wire experts, signal teams and mechanical crews.
"It is subject to the wear and tear that has gone one for the lats 118 years," the spokesman said, and could take several hours to repair.
Riders are advised to listen for announcements at stations for updates on the situation. and to expect crowded conditions
Commuters took to Twitter once again to lament the delay to their train service.
Stephen Wood under his twitter handle @CTMQ, said "Hey, at least the weather is nice for the 1000's of people stuck on #MetroNorth AGAIN today. pathetic."
Joe M at twitter handle @Joemanc31 questioned the opening of the bridge. "Why do they even open that bridge in Sono? It's not like tall cruise ships are passing through! #metronorth."
Still others spoke out about delays to their weekend plans and using hashtags like #failroad to express their frustrations.
This spring, the state announced a $465 million project to cover the cost of the Walk Bridge replacement, with $349 million in federal funding and $116 million in state funding.
The money will be used for project design, engineering, environmental clearance, and construction. Replacing the Walk Bridge with a drawbridge (which would open for marine traffic from one side with a counterweight system) would enhance the safety and reliability of commuter and intercity passenger service along the Northeast corridor, the Connecticut Department of Transportation said.
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