​​This information is preliminary and subject to change.

​Release date 6 August 2025

​On July 6, 2025, about 3:19 p.m., local time, southbound Canadian National Railway (CN) train A48871-06 derailed 21 mixed-freight railcars on the Grenada Railroad near Sardis, Mississippi.[1] The derailment occurred on the south end of a 130-foot-long bridge.[2] The derailed equipment included four tank cars carrying hazardous materials, two containing sulfuric acid and two containing sodium hydroxide. One of the tank cars was mechanically breached during the derailment and released about 10,500 gallons of sodium hydroxide.[3] CN and Grenada Railroad estimated damages to be about $2 million. No injuries were reported. Visibility conditions at the time of the accident were partly cloudy with no precipitation; the temperature was 93°F.

​The train crew, consisting of one engineer, one conductor, and one Grenada Railroad pilot who was operating on the Grenada Railroad to bypass a track outage on CN’s Yazoo subdivision because of a derailment the previous day in Glendora, Mississippi.[4] The engineer was using dynamic braking to control the 12,311-ton train’s speed as it travelled down a 0.9% downhill grade.[5] At the time of the accident, the train was travelling about 24 mph (the maximum authorized speed at the location of the derailment was 25 mph) when an undesired emergency automatic brake application was initiated when the train’s air brake line lost pressure.[6]

​Train A48871-06 train was 7,002 feet in length with 114 mixed manifest railcar consist and three locomotives on the head end. Review of the outward-facing video of the lead locomotive shows an “S-curve” misalignment of the track on the south end of the bridge as the train approached the bridge. This track was designed as tangent or straight track across a bridge. Twenty-one railcars, the 41st to the 61st behind the locomotive, derailed from train A48871-06 as it passed over the track with the misalignment.

While on scene, National Transportation Safety Board investigators inspected the railcars involved in the accident; examined conditions of the track and bridge; performed a preliminary review of event recorder data from the lead locomotive and the video from inward- and outward-facing image recorders; reviewed Grenada Railroad radio and phone communications; collected select railcar components for further examination; reviewed railroad crew and staff training programs, company policies, and procedures; and conducted interviews.

The investigation is ongoing. Future investigative activity will focus on Grenada Railroad track and bridge maintenance procedures, CN operating rules related to train operation and assembly, and in-depth analysis of event and image recorder data. In addition, rolling stock engineering and manufacturing processes will be reviewed as they relate to the railcars involved in the derailment.

Parties to the investigation include:

• ​the Federal Railroad Administration; 
• the Pipeline and Hazardous Materials Safety Administration; 
• Canadian National Railway; 
• ​Pinsly Railroad Company; 
• the Brotherhood of Locomotive Engineers and Trainmen; 
• the International Association of Sheet Metal, Air, Rail and Transportation Workers; and 
• Brink Engineering Solutions, LLC.