A quantitative analysis of Kamativi's water quality
Thesis DisciplineWater Resource Management
Degree GrantorUniversity of Canterbury
Degree NameMaster of Water Resource Management
Kamativi is a tin-mining town in north-western Zimbabwe, in Hwange district of Matabeleland north province. The population of the town, and its peripheries, is an estimated 7,000 people, most of whom are former miners, laid off from work following closure of the mine in 1994. Mining operations ran for about 58 years prior to then, before low tin prices at the time forced indefinite suspension of business. The Hwange Rural District Council (HRDC) subsequently took over the administration of the town from the Zimbabwe Mining Development Company (ZMDC). This takeover included the running of the town’s water supply system which uses surface abstraction from a local dam to supply its reticulated system. The mine was the main source of economic income in the area so its closure led to deterioration of everything in Kamativi, and water problems have dogged the town ever since. Prompted by media reports about poor water quality, and availability problems cited by residents, this research was undertaken into the physico-chemical and microbiological characteristics of Kamativi’s water supply, and how it compares to Zimbabwean drinking water standards and guidelines. The purpose was to determine the impact, if any, of mining and other anthropogenic activities on the quality of water in Kamativi, and to suggest a way to improve or resolve Kamativi’s water quality issues. Samples from different water sources in Kamativi were collected during part of the wet and dry seasons in 2016. Arsenic concentrations exceed the Zimbabwe and World Health Organization’s health-based guidelines for drinking, in five out of six main sources, including tap water. Two other water sources had concentrations of aluminium and manganese that exceeded the standards on at least one occasion. The distribution of trace metal concentrations by geographic location of the water bodies suggests that proximity to the mine influences the concentration of trace metal pollutants. Faecal contamination was evident in raw water, as indicated by the presence of E. coli and faecal coliforms. It was concluded that the water did not meet the standards for drinking water and needs treatment. It was also determined that the mine has an impact on the water quality and there is a risk of arsenic toxicity. A recommendation was made that Kamativi reintroduces full water treatment and treats for trace metals, particularly arsenic. Ongoing monitoring and evaluation is also needed to gauge improvements, lessen pollution, and prevent future impacts. Further research is required to determine the source and speciation of arsenic within the mining area and to predictively assess impacts of the proposed reopening of the mine on the local water supply system.