Impacts of Climate Change on Water Yield in Lake Kyoga Catchment: A Case of Akokorio and Kapiri Sub-catchments

Abstract

Lake Kyoga basin is largely under semi-arid characteristics with limited water resources and sensitive to climate change. Previous studies reveal that the region is prone to occurrence of extreme wet and dry climatic events. This research assessed the effect of the climate change on water yield in Lake Kyoga basin. Daily rainfall data (1980 to 2014) was obtained from the Uganda National Meteorological Authority (UNMA). Land use data (2000 to 2015) was obtained from the National Forestry Authority (NFA) Uganda and processed using ArcGIS 10.1. Data on water levels and flow (1980 to 2014) was obtained from the Directorate of Water Resources Management Uganda and processed using Correlation Percentage Change (CPC) to examine changes in water storage and flow. The Mann Kendall (M-K) trend test tool was applied to establish the cumulative change in rainfall and flow. Open water and wetland areas reduced by 11% and 4%, respectively. A 3% negative change was observed in water levels of Lake Kyoga with exception of February and September that showed +3% from 1980 to 2014. The flow at Masindi port (out let of Lake Kyoga basin) was observed to decrease over time, contrary to increasing precipitation patterns. The water levels for Akokorio and Kapiri sub basins were however observed to have increasing trends. Climate change was not found to affect water yield in Lake Kyoga catchment though negative climatic observations and severe events were observed, and are expected to happen in the future. Mitigation methods should support the implementation of catchment management strategies in Lake Kyoga basin to sidestep the long-term forthcoming negative consequences of land use change which was observed as a major threat to the catchment