Extent and economic significance of landslides in Sweden

Landsliding is a natural hazard in many parts of Sweden. Many kinds of landslide occur, but clay slumps, in places developed into large quick-clay landslides and river and gully erosion in silt soils are the most common types of mass movement. Their occurrence coincides with many densely populated areas, where they are of great concern to authorities and individuals. In the less populated mountain areas, many kinds of mass movements occur, such as slumps, soil creep, debris and mud flows, debris avalanches, silt erosion, rock slide and rock fall. The mass movement hazard in mountain areas is more and more related to increased development. Rock slide and rock fall outside the mountain range occur locally on confined sites such as steep fault slopes and steep excavated rock slopes, e.g. for roads. The catastrophic landslide in Tuve, Gothenburg, in 1977, increased the consciousness of landslide risk in Sweden and this has resulted in increased concern by municipalities and county administrative boards, a new national policy on landslide risk (1986) and the establishment of a Commission for research and information on landslide problems (1988). The governmental cost of stability reinforcement works in emergency cases amounted in 1987 to about 2.5 million $US. In 1985 one site was reinforced for about 7 million $US. In the city of Gothenburg, several slopes have been stabilized during 1983–87 for about 11 million $US.