Impact of Drought on Ground Water Quality in Langata Sub-County, Kenya

Abstract

A quality decline trend is suspected to be ensuing in the water originating from boreholes in Langata sub-County; a region located to the south of Nairobi, the capital city of Kenya in East Africa. Despite the existence of this worrisome suspicion, no investigation has been conducted to assuage the fears of the exposed population. This situation however contradicts the great augmenting role of borehole water delivered by vendors to consumers as a coping strategy against the pervasive drought induced water shortage challenge afflicting households in Langata. Hence, a question arose as to whether the identified past drought events have had any chance of influencing the ongoing declining trend of the area’s ground water quality. The purpose of this study was therefore to assess the impact of historical drought events on the ground water quality in Langata Sub County. The profile of drought indices was superimposed over the area’s time series geochemical water quality indices’ profile. Further, the computed area’s groundwater potability grade was used to estimate the probability of water quality deterioration due to drought impact, returning a value of 43.65%. It was found that indeed, ground water quality in the area is on a declining mode. Since water is an elixir of life; the finding from this study is expected to trigger an establishment of a water quality surveillance initiative as a safeguard to public health.