Impact of On-Site Sanitation and Siting of Boreholes on Ground Water Quality in Choma Urban: A Case of New Kalundu and Humba Residential Areas

Groundwater is a climate–resilient source of freshwater for most sub–Sahara African countries and plays a vital role in sustaining improved access to safe water in pursuit of United Nations Sustainable Development Goal 6 – water and sanitation for all by 2030. However, the potential for on-site sanitation to cause major contamination to groundwater has been known for many years, prompting authorities to advise minimum safe distances between boreholes (water sources) and soakaway. This study evaluated the effects of on-site sanitation and borehole placement on the quality of groundwater in residential areas. The study employed an embedded mixed methodology with a descriptive cross-sectional approach. 138 household heads were involved in the study and 15 water samples were collected for microbiological analysis. Data from households was collected using structured questionnaires while upholding all ethical issues. The study found that 85% of households used on-site sanitation systems as their primary means of waste treatment and disposal, while the remaining 15% used other methods like pit latrines. Due to the utility company’s unstable and unreliable supply of water, residents turned to alternative sources of drinking water, such as drilling boreholes and hand-dug wells within and around compounds, using soakaway systems for waste disposal close to the drinking water source. The chi-square tests revealed that the position of the soakaway, as well as the distance between the water sources and the soakaway, have an influence on water quality. The study concluded that establishment of water sources near any pollution source (soakaway) has a negative impact on the quality of groundwater resources. We recommended that local authorities should not permit construction at any plot less than 30 x 30 meters in its dimensions to have both borehole and on-site sanitation system but rather one of the two.