On June 28, a Canadian National (CN) freight train derailed in the St. Clair Tunnel near the U.S. city of Port Huron shortly after 06:00 (local time), forcing authorities to temporarily halt traffic through the tunnel. Operated by Canada’s largest rail operator CN, the St. Clair Tunnel is a key border tunnel for freight trains carrying chemicals and cars between Chicago and Toronto. As the second busiest U.S.-Canada border crossing for rail traffic, even a short-term closure is likely to cause substantial delays in regional cargo movement.
During the derailment of the train, 13,000 liters of highly-concentrated sulfuric acid leaked from one of the 46 derailed rail cars into containment tanks within the rail tunnel, complicating efforts to safely remove the wagons. As of July 1, more than 20 cars, including multi-level auto carriers, have been removed and the clean-up operation is expected to have been completed that same evening. Initial statements by CN indicate, however, that large parts of the track will need be replaced due to the effects of sulfuric acid, which will likely put the tunnel out of service for several weeks.
According to U.S. rail operator Amtrak, which uses a nearby route, the blocked St. Clair Tunnel has already caused congestion for freight trains throughout the region since June 28, backing up freight traffic on the line from Port Huron to Chicago. Freight trains are likely to be re-routed to alternative border access points during the closure, but these efforts are expected to be constrained by several factors, such as whether the tracks are able take double-stack containers and if CN has agreements in place with the rail operators of other border crossings. The nearest alternative rail border crossing is the Michigan Central Railway Tunnel in Detroit, which is owned by CN’s domestic competitor Canadian Pacific Railway (CPR), highlighting the complexity of any re-routing efforts for freight trains on this line. Depending on the origin and destination of the train, CN may also use the border crossing at Niagara Falls-Buffalo on the eastern end of Lake Erie, which is operated by both CPR and CN.
Customers with an interest in rail freight moving between Chicago and Toronto should expect delays to persist until repair works are completed and contact their carriers to investigate if there are any additional transit times for their shipments as a result of the accident.