Red Line train derailed at JFK/UMass Station. (Photo by Boston Fire Department via Twitter)

A RED LINE TRAIN derailment at the JFK/UMass Station early Tuesday morning plunged the city of Boston into a far-worse-than-usual gridlock.

The derailment occurred at about 6 a.m. at one of the major choke points on the MBTA system, where the two southern branches of the Red Line converge. As a result, the T had to scramble to run replacement buses from North Quincy to Broadway on the Braintree branch of the Red Line and between Ashmont and Broadway on the Ashmont branch of the Red Line.

But the shuttle bus service, after it was established, failed to move passengers along because the vehicles were stuck on roads that had turned in to virtual parking lots. I was able to board a bus on Dorchester Avenue near the Shawmut Station T stop at 8:02 a.m. and didn’t reach the Red Line Broadway Station – five stops away – until 9:47 a.m.

It was unclear why congestion was so bad and seemed to extend well beyond the immediate area impacted by the Red Line shutdown. One theory was that the derailment happened early enough that many people who normally would have ridden the T decided to drive into town. The congestion may have been worsened by the decision by emergency personnel to shut down the exits off of the Southeast Expressway near JFK/UMass (Columbia Road) for about 30 minutes – from 7:10 a.m. to 7:42 a.m.

There also appeared to be no police presence at major intersections trying to keep traffic moving along.

MBTA replacement buses during the early morning commute were packed. (Photo by Bruce Mohl)

Jim Aloisi, a board member of TransitMatters and a former secretary of transportation, said it appeared to him that there was no coordinated emergency plan in place for such a situation. The T has protocols for such situations, but in this case the protocols didn’t seem to be coordinated with Boston emergency officials.

“What’s the plan?” he asked. “Everything just broke down. The traffic was unbelievable.”

Aloisi also found it interesting that the T reported switching problems on Monday night at JFK/UMass. An MBTA tweet at 5:11 p.m. on Monday reported “delays of up to 15 minutes due to a switch problem at JFK/UMass. Trains may stand by or move slowly as they are given permission to move through the area.”

On the same Twitter thread, a person commented that “this has to be about the fifth time this week that the Red Line is delayed because of some problem at JFK.”

Some commuters who took Uber reported astronomical surge prices of more than $100, but officials with the ride-hailing app said the surge pricing was discontinued in the immediate area of the derailment as soon as they learned of the incident.

The train that derailed was headed to Braintree when a car in the middle of the train derailed and leaned to the side. Passengers were taken off the train by emergency personnel. Only one was injured; none were taken to the hospital.

The Red Line derailment follows close on the heels of a derailment on the Green line Saturday that injured 11 people, including the driver. That incident was blamed on operator error, although T officials say they are still investigating.

Bruce Mohl oversees the production of content and edits reports, along with carrying out his own reporting with a particular focus on transportation, energy, and climate issues. He previously worked...