Beavers have been blamed for a train derailment that spilled more than 20,000 litres of diesel fuel into the Ottawa River, which supplies the drinking water for the Canadian capital.
In a statement on Friday, Ottawa Valley Railroad said the collapse of three beaver dams late on Wednesday released a wall of floodwater up to 3.5 metres high that rolled across the tracks, 300km north of Ottawa.
Nearly 200 metres of track was destroyed. Two locomotives and six empty railcars used to haul lumber were derailed.
One of them ended up in the river and flushed 20,450 litres of diesel fuel into the river.
The train crew experienced minor injuries.
However, authorities said there was no immediate threat to Ottawa's drinking water or wildlife in the area.