Influence Of On-Site Sanitation Systems On Shallow Groundwater Quality In Kimpwena Settlement, Solwezi District, Zambia
Year: 2026
Type: article
Abstract: Shallow groundwater is a primary source of domestic water for millions of peri-urban households across sub-Saharan Africa. Unfortunately, its quality is increasingly compromised by the widespread use of on-site sanitation systems. This study assessed the influence of pit latrines on shallow groundwater quality in Kimpwena Settlement, Solwezi District, Zambia, using a descriptive cross-sectional design that combined GIS spatial analysis with laboratory water quality assessment. Four sentinel shallow wells (n = 4), purposively selected to represent a range of distances (6 - 29 m) from the nearest sanitation facilities, were sampled during the rainy season and analysed for physicochemical parameters: pH, electrical conductivity (EC), total dissolved solids (TDS), turbidity, nitrate (NO₃⁻), and phosphate (PO₄³⁻) as well as microbial indicators, including faecal coliforms and total coliforms. A sentinel-site approach was employed to identify contamination gradients rather than generate statistically representative estimates of groundwater quality. Results were benchmarked against Zambia Bureau of Standards ZS 190:2010 and WHO 2017 drinking water guidelines. GIS analysis confirmed that all sampled wells were located within 30 m of sanitation facilities, in non-compliance with recommended separation distances. Groundwater was universally acidic (pH 4.71 - 5.30), and phosphate concentrations exceeded permissible limits at three of four wells (1.6 - 3.2 mg/L; limit: 1.0 mg/L). Severe microbial contamination was detected at the well with the shortest proximity to sanitation, recording faecal coliforms of 224 CFU/100 mL and total coliforms of 320 CFU/100 mL, suggesting an inverse distance-contamination relationship. EC, TDS, and nitrate concentrations were within acceptable limits across all locations, likely reflecting seasonal dilution and denitrification dynamics. These findings demonstrate that inadequate separation distances, combined with permeable soils and high sanitation density, appear to contribute to groundwater contamination in Kimpwena Settlement. The study recommends stricter enforcement of siting regulations, infrastructure upgrades, enhanced well protection, and community-centered awareness programs to safeguard groundwater quality and protect public health in peri-urban Zambia.
Authors: Misheck Chisuku, Allan Tembo
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W7225239658