Potential effects of changes in climate, land cover and population on the quantity of ater resources in lake nakuru and lake elmenteita areas, kenya

Abstract

This study evaluates the potential effects of changes in climate, population and land cover on the quantity of surface water and groundwater resources in Lake Nakuru and Lake Elmenteita areas. Multiple linear regression analysis of the variables was done using Statistical Package for Social Sciences (SPSS) to achieve this objective. Population grows in the area at the rate of 3.4% to 4.5% while natural vegetation cover is diminishing at 2.5% annually. There is constant rise in daily minimum temperature while there is a rise in the mean annual precipitation. The area’s domestic water demand per capita is projected to rise from 50 litres per day in 1971 to 160 litres per day in 2030. This, based on the rate of population growth, will translate to a soaring total demand of 174,000,000 m3 annually by the year 2030. Strong positive correlation between precipitation and discharge is observed, indicating that rainfall is the main source of surface water in the area. The precipitation is thus expected to influence the occurrence of extreme events, with droughts projected for the year 2001, 2012, 2016, 2021 and 2028 while floods are projected to occur in 2006, 2009, 2018, 2024 and 2030. To mitigate against the deteriorating surface and groundwater resources in the area, there is need to restore Mau escarpment since it is the most affected. Resettlement of the inhabitants will be key to ensuring sustainable water supply. The reforestation of Mau catchment should take into account promoting cross-breeding to produce superior tree species. These species should be fastmaturing, heat-and-drought tolerant and pest-and-disease-resistant. Measures that are recommended to reduce green house gas emissions and vegetation loss include slowing deforestation, enhancing natural forest generation, establishing tree plantation, promoting agroforestry and altering management of agricultural soils and rangelands. Enhanced resilience to future periods of drought stress can be supported by improvements in present rainfed farming systems, such as water harvesting systems to supplement irrigation practices in dry areas. Improved early warning systems and their application may also reduce vulnerability to future risks associated with climate variability and change. Increased investment in dams will improve harvesting of water that would cause flooding during heavy rains. This would later be used to mitigate against the effects of droughts.