On August 20, 1969 at about 8:20 p.m., a northbound commuter train with a 3-man crew and about 60 to 80 passengers hit an empty southbound train carrying only 5 employees, killing 4 and injuring 40 just north of the
Hoyt Street crossing in Darien. The lead cars of each train were almost completely destroyed. The
National Transportation Safety Board report concluded that the cause was the northbound train's failure to stop at a meeting point as stated on train orders. On July 13, 1976, two trains collided, killing two and injuring 29. In October 1976, the CDOT released their report which only blamed the
engineer of the northbound train (Number 1994) for excessive speed. The engineer's
union contended that there was a problem with the train brakes, that there was an automatic track lubricator which had been putting down excessive oil for two weeks before the incident and an insufficient
signal system. The National Transportation Safety Board released their final report on the incident on May 19, 1977 as Report Number RAR-77-04. That report concluded that the cause was "the failure of the engineer of train No. 1994 to perceive the train ahead and to apply the brakes at the earliest possible time". It also cited problems with the design of the signal system, design of the M2's exit doors and interior design of the trains. The New Canaan Branch was severely impacted by
Hurricane Sandy on October 29–30, 2012. The line was blocked by fallen trees in 37 different locations; many of these trees also brought down the
overhead catenary wires. Shuttle buses replaced all trains. The railroad announced that regular service resumed on November 13. This resumption was marred by
slippery rails caused by rain and fallen leaves, to the extent that service had to be shut down again that afternoon to deploy Metro-North's rail-washing train. Train service resumed in time for the evening commute. On February 14, 2023 at approximately 7:30 a.m., an out of service train being moved to enter passenger service overran the New Canaan station, running through the bumper block and crashing through the station fencing before coming to a stop. The engineer and conductor onboard were injured, but not seriously. While this incident caused a suspension of service on the branch throughout the morning rush and midday hours; following repairs, service was restored with the 4:39 p.m. train from Stamford. ==Stations==