Overview:
120 people have been evacuated from a derailed train near Hudiksvall after heavy rainfall brought by Storm Hans caused embankment failure
The Landslide Blog is written by Dave Petley, who is widely recognized as a world leader in the study and management of landslides.
On Monday 7 August 2023, a regional train was derailed close to the town of Hudiksvall in Sweden as a consequence of an embankment failure. The event occurred during heavy rainfall associated with Storm Hans in both Sweden and Norway that has triggered extensive damage, including widespread flooding and landslides. At the time of writing, rain is continuing. In Norway, there are reports of a significant landslide at Bagn in Valdres that has damaged or destroyed several houses, for example.
At Hudiksvall, the train was derailed at about 12:30 pm. The best set of images that I have seen was tweeted by railway enthusiast Chris Ogilvie:
The train was carrying 120 people, but only three were injured. The damage was limited by a decision to reduce the running speeds on this section of track following a ride quality report from the driver of an earlier train.
The images above suggest that the Hudiksvall failure was complex, and is a little difficult to interpret, so I can only speculate. The images at the front of the train appear to show a significant washout of the track bed, which in itself would have been enough to derail the train. It appears that there was a culvert at this point, but I suspect that its capacity was exceeded. If so, that could have caused water to flow over the track, inducing the washout. Water might also have flowed along the track bed, then down the embankment, causing what appears to be significant disruption to the slope.
I am speculating of course – the accident is being investigated formally.
The accident appears to have occurred in the region of [61.698093, 17.103638], close to Hudiksvall. There is a culvert at that point in the track. If so, this is the location on Google Earth:
Modern rail infrastructure should be able to deal with heavy rainfall, so an interesting aspect of this accident will be to understand why the culvert failed. This failure has some similarities to the Stonehaven rail accident in Scotland, although it was much less serious. The subsequent Network Rail Earthworks task force report, for which I was a co-author, is also highly relevant.
Acknowledgement
Many thanks to Pascal Orrit, who highlighted this event to me and identified the likely location.