Investigation of the impact of pit latrines on groundwater in Matlerekeng area

Abstract

South Africa is one of the developing countries in the world which is dominated by rural areas. In such countries supplies of basic services such as water and sanitation facilities are a challenge. As a result, the available water sources become compromised. The Department of Water and Sanitation developed a National Water Resource Strategy (NWRS) to help to address such problems across the country. The area under study is Matlerekeng which is commonly known as Zuurbekom under EMLM. The area was developed during the apartheid era when town planning schemes where not effective. As a result, the community is scattered which makes the distribution of services costlier and the internal roads are also not properly planned. As a result, the community members use pit latrines for sanitation and abstract water from boreholes for domestic use. Pit latrines are known to be common causes of groundwater pollution in rural areas. Groundwater pollution is accelerated by different factors such as the type of aquifers, the soil and the topography of the area. The soil nutrients might also contribute to contamination of groundwater. E. coli is the most common bacteria found in human excreta. The presence of these bacteria in groundwater in most cases depends on the availability of pit latrines, sewage and agricultural activities. For the determination of the pollution of groundwater by pit latrines in the Matlerekeng area, samples from domestic boreholes were taken for analysis. The chemical parameters such as nitrate and ammonia together with E. coli bacteria were analysed. The samples were collected using specified bottles as per groundwater sampling guideline by Department of Water and Sanitation (WRC, 2007) and taken to accredited laboratories for analysis. The sampling points were selected randomly in the area depending on availability and use. The results were analysed and compared to the South African National Standard (SANS), 2015 water guidelines for domestic use. In addition, the vulnerability of the aquifer to pollution was also determined