Landslides and mud flows

Throughout the Kivu basin region, landslides represent the most severe hazard at local scale. The widespread distribution of these mass movements is shown by the newly developed on-line database “The natural hazard database for Central Africa”.  In the study area, landslides can be triggered both by climatic events (strong rainfall) as well as seismic or volcanic (mudflows) activity, or even by combined effects. The potential impact of these landslides is increased by anthropogenic factors. Moreover, it has been found that the frequency and magnitude of mass movements and their effects in urban areas in Central Africa (such as Kinshasa, Bukavu, Uvira, Mbuji-Mayi, Butembo and Bujumbura) are much greater than what can be expected if only natural factors are taken into consideration. In Bukavu, for instance, both the rift escarpments and Lake Kivu limit the urban expansion. Therefore, the population is forced to settle in increasingly unsuitable areas, resulting in numerous examples of major roads or houses constructed on slopes affected by landslides or rock falls.

In the Virunga Volcanic Province, strong rainfalls often trigger torrential events on the volcano flanks, especially along the flanks of the central and eastern volcanoes. These torrents are able to mobilize large amounts of unconsolidated deposits and develop in fast and devastating mudflows. The last lethal mud flow event occurred in May 2010 and affected the village of Kibiriga, in DR Congo.

The May 2010 Kibiriga Event