Impact of Pit Latrines on Enteric-Pathogen Contamination of Groundwater in Tigania West Sub-County, Kenya

Access to safe water and sanitation remains a challenge in many developing regions, where pit latrines are the dominant sanitation option. Their proximity to groundwater raises concerns about fecal contamination and related health risks. This study examined the effect of pit latrines on enteric-pathogen and physicochemical contamination of groundwater in Tigania West Sub-County, Meru County, Kenya. A cross-sectional design was applied, with water samples collected from 96 households across five wards. Groundwater samples were obtained from boreholes and wells located within 30 meters and beyond the recommended setback distances from pit latrines. Microbiological analyses targeted total coliforms, Escherichia coli, Salmonella, Shigella, and Staphylococcus aureus, while physicochemical parameters including pH, turbidity, colour, odour, and biochemical oxygen demand (BOD) were measured. The results revealed high levels of microbial contamination across wards. Total coliforms were most prevalent in Athwana (1.08/100 ml) and Mbeu (0.80/100 ml), while E. coli contamination was highest in Athwana (0.23/100 ml). Salmonella was widespread, with Nkomo (0.82/100 ml) and Athwana (0.92/100 ml) showing the greatest occurrence. Staphylococcus aureus ranged from 3.8/100 ml in Kianjai to 7.23/100 ml in Athwana, exceeding WHO permissible limits. Overall, wards with pit latrines situated within 30 meters of water sources such as Mbeu (86.7%) and Nkomo (76.5%) recorded significantly higher contamination. These findings underscore the role of pit latrines in groundwater pollution in Tigania West and highlight the urgent need for improved siting, design, and management of sanitation facilities to safeguard public health.