The Effects of Water Transfer from Swakoppoort and Omatako Dams on the Water Quality of Von Bach Dam, Namibia

Abstract

This chapter presents the outcome of research conducted in Otjozondjupa region, central Namibia on the effects of water transfers from two storage dams (Swakoppoort and Omatako Dams) to augment water volume in a third dam (Von Bach Dam) which is located closer to a purification plant. The transfers are strategically made to bring water closer to the purification plant and more important to limit evaporation losses from the wider and shallower dams; Von Bach Dam is much narrower and deeper than the other two dams which together, constitute the source of water for the expansive residential area and industrial hub located in the capital city of Windhoek and its environs. The study investigates water quality in the three dams and analyses the effects of water transferred and possible effects on water treatment costs. Research findings are discussed and analyzed using relevant models for predicting water quality changes. The results from the secchi disk depth measurements and the analysis of turbidity, dissolved oxygen; iron, total phosphorus, ammonia (NH4–N) and chlorophyll a indicate that there were significant negative effects resulting from the water transfers. Other parameters tested indicate that there were no statistically significant differences in the three dams.