Scientific and indigenous knowledge understanding of rainfall induced landslides in Murang’a County, Kenya

Abstract

The East African region has reported major landslides and Kenya is indeed characterised as a disaster-prone country. Landslides are a recognised but poorly studied phenomenon in the Eastern foot-slopes of the Aberdare Ranges in Central Kenya. A dearth of information about landslides has been cited in the country. Landslides in Murang’a County are known to occur especially during the two rainy seasons and has been recurring in the recent past. Such a scenario makes rainfall factor of interest in understanding the landslide occurrences. People living in landslides prone areas are said to have huge experiences and knowledge about landslides but have remained hugely unexploited. The adaptation and integration of both the scientific and indigenous knowledge may be an option to increase the understanding of landslide disaster risks in the prone areas. The aim of this study is to fill the existing gap in the understanding of the recurrent landslide disaster risks in Murang’a County through an investigation of the rainfall as a major causal/trigger factor as viewed through both indigenous and scientific understandings. Primary data were collected through household questionnaires administered to a total of 336 household heads, complemented with 8 Key Informants Interviews and 6 Focus Group Discussion interviews conducted across the study administrative locations. Quantitative data were analysed through descriptive and inferential statistics in the SPSS package. Secondary data obtained from remote sensing were quantitatively analysed using Raster-GIS in ArcGIS software. The study findings showed that Rainfall is a major factor in causing/triggering landslides in Murang’a County as understood by experts from among other institutions the meteorological department, where a rainfall threshold of 1,160mm mapped99% of the March-April-May 2018 reported landslides in the ‘high risk zones’. Rainfall factor had an approval rate 98% as being the most prominent landslide contributing factor as viewd by the indigenous people. In conclusion, both scientific and indigenous knowledge concur that rainfall is a major landslide causal/trigger factor in Murang’a County. The study recommends that since landslides are highly localized, an in-depth research on other causal/trigger factors using both scientific and indigenous knowledge should be done, especially in areas which have previously been affected by landslides. Such would give a better understanding of landslides in terms of the causal or trigger factors with the aim of enhancing the disasters management in the county and formulating a policy framework integrating the two levels of knowledge.