Department of Planning, Faculty of Planning and Land Management, University for Development Studies, Tamale, Ghana.
School of Geography, University of Nottingham, NG7 2RD Nottingham, United Kingdom.
Sci Total Environ. 2021 Jan 15;752:141846. doi: 10.1016/j.scitotenv.2020.141846. Epub 2020 Aug 20.
This paper examines seasonal variations in faecal contamination of drinking water sources in the Jirapa and Kassena-Nankana Municipalities of Ghana. Data collection involved a survey of 568 households, testing of faecal coliform concentrations in drinking water source samples (141 in the rainy season, 128 in the dry season), in-depth interviews with key water stakeholders, and field observation to identify sources of faecal contamination. From the water quality testing, faecal coliforms were detected in all source types, including 'treated' pipe-borne water. Contamination was significantly higher in the rainy season than in the dry season (P < 0.05) with 51.8% of water samples in the rainy season and 27.3% in the dry season failing to meet the World Health Organisation and Ghana Standard Authority guideline on faecal coliform concentrations in drinking water sources. The proportion of population at risk of faecal contamination in the rainy season was 41.5% compared to 33.1% in the dry season. We argue that in Ghana and Sub-Saharan Africa at large, water surveillance agencies risk underestimating population exposed to faecal contamination through drinking water sources if monitoring is only done in the dry season. To avoid this, we recommend seasonal monitoring of faecal concentration in drinking water sources. However, in periods of limited resources, monitoring is most appropriate in the rainy season when the risk of contamination is high.
本研究考察了加纳杰拉帕和卡萨内-南卡纳市饮用水水源粪便污染的季节性变化。数据收集包括对 568 户家庭进行调查、检测饮用水源样本中的粪便大肠菌群浓度（雨季 141 个，旱季 128 个）、对主要水利益相关者进行深入访谈以及实地观察以确定粪便污染来源。从水质检测结果来看，所有水源类型都检测到了粪便大肠菌群，包括“处理”的管道供水。雨季的污染明显高于旱季（P<0.05），雨季的水样中有 51.8%，旱季的水样中有 27.3%不符合世界卫生组织和加纳标准局关于饮用水源中粪便大肠菌群浓度的指南。雨季有粪便污染风险的人口比例为 41.5%，旱季为 33.1%。我们认为，在加纳和整个撒哈拉以南非洲，水质监测机构如果仅在旱季进行监测，就有可能低估通过饮用水源接触粪便污染的人口。为避免这种情况，我们建议对饮用水源中的粪便浓度进行季节性监测。然而，在资源有限的时期，监测最适合在污染风险高的雨季进行。
