The El-Nino-triggered landslides and their socioeconomic impact on Kenya

Kenya experienced extraordinarily heavy rainfall between May 1997 and Febru ary 1998 due to the El-Nino weather phenomenon. This period of about 10 mon ths heavy rainfall caused wide spread landslides and floods which were expe rienced in various parts of the country. Normally mid-December to late Marc h is the driest and hottest season in Kenya. However, during this period, t he season turned out to be the wettest with one of the heaviest precipitati on events recorded in the country in the past several decades. Research inv estigations have revealed that the landslides were a result of four major f actors. The factors included, geology and soils of the landslide prone area s, high relief, steep slopes with poor anchorage for slope stability, conti nuous heavy precipitation which resulted into oversaturation of rocks and s oils. The effects of the El-Nino-triggered landslides in Kenya were enormou s. Although statistical data about landslide destruction are not presently quantified, human and animal fatalities and plant destruction were enormous . Fertile farmlands, roads, railway lines, bridges, telephone and power lin es were relocated and destroyed. Soil erosion which increased from higher s urface runoff and surface exposure filled rivers with sediments. The sedime nts were transported to the hydro-electricity producing dams which eventual ly became clogged and power generation stopped. The national economic loss to the country is estimated at about US $ 1 billion and will take a long ti me to recover.