Impact of settlements, agriculture and industries on protected springs’ water quality in Lugazi Municipality

Abstract

Groundwater is a reliable source of drinking water for many people, especially in developing countries where access to piped water is limited. In Uganda, like other developing countries, many low-income communities rely on untreated groundwater, mainly from protected springs, for drinking and other domestic uses. However, with ever-increasing human activities coupled with poor waste disposal, groundwater quality requires good attention due to the possible risk of contamination that could lead to water-related diseases. Therefore, this study sought to assess the effect of anthropogenic activities (settlements, agriculture, and industries) on: a) physico-chemical properties (pH, EC, TDS, and Turbidity) b) Trace elements (Pb, As, Ni, Cu, and Cr) and nutrients (Ammonium and Nitrate) content and c) microbial contamination (TC and E. coli) in protected springs within Lugazi Municipality. Sampling of water from springs located in Lugazi Municipality was done and control samples were also collected from Ssi-Bukunja and Ngogwe sub-counties with low human activities. In-situ measurements of the Temperature pH, EC, and TDS were carried out using portable multi-parameter devices whereas nitrates, ammonium-nitrogen, trace elements (Cu, Pb, As, Ni, Cr), E. coli, and TC were analyzed from UNBS analytical and microbiology laboratories. From the study, all trace elements tested except Cu were below quantifiable concentrations in all samples. Although Cu was recorded at all the sampling sites, the concentration values obtained were below the limit of 2 mg/L recommended by WHO (2017) & UNBS (2014) standards for drinking water. The Cu concentration values recorded at all sites in the study area were not significantly different from those recorded at the control sites. The E. coli and TC in the study sites were significantly higher than those recorded from the control sites. The study further revealed that 12.5% of sampled springs in all the divisions of the municipality had nitrates higher than the UNBS and WHO limits, 100% of the sampled springs had TC numbers above UNBS limits while 72 %, 68 %, and 100% of springs sampled in Najjembe, Kawolo and Central Divisions of Lugazi Municipality respectively recorded E. coli counts that were far above the WHO set limits. The pH values recorded in the study area were below the limits of UNBS and WHO for drinking water. Generally, water from the protected springs in Lugazi Municipality which had a higher level of human activities registered higher Levels of contamination compared to water from control areas. The study suggests that the groundwater of the area needs to be treated before consumption and also be protected from exposure to anthropogenic contamination.