On January second 2012 Byneset near Trondheim has been struck by a massive landslide prompting evacuation of dozens people. The river of muddy black sludge stretching about a kilometer (over half a mile) was moving through the area. See video from the slide area http://tiny.cc/7xbx3w
This is a natural process that takes place when running water goes with the material, or moving soil from one place to another.
The slide occurred in a stream section, in the very flat landscape. No people or homes were taken off the slide, but less than 50 people have been evacuated. Recovery process will take years.
This is how Byneset looks like one and a half years later.
Mountain Man - She Loves Me So Much.