Review: Current groundwater monitoring practices in Rwanda and recommendations for enhancing knowledge of groundwater resources

Abstract Although groundwater serves as the predominant source of drinking water across many rural regions and certain urban areas of Rwanda, little is known about this resource. Anthropogenic impacts, such as faecal contamination, as well as geogenic water quality problems, including elevated arsenic, fluoride, iron, and manganese, are among the issues of concern for groundwater quality in Rwanda. Long-term groundwater monitoring can provide data on the evolution of groundwater quantity and quality. It helps to identify trends related to over-abstraction, reduced recharge, and pollution, which supporting resource management decisions. This review assesses the current state of groundwater monitoring in Rwanda by identifying the strengths and weaknesses of existing monitoring efforts, knowledge gaps, and opportunities for improved groundwater monitoring and management. The findings indicate that groundwater quality assessments are only conducted for specific purposes without considering broader issues and that groundwater monitoring in Rwanda is, in many respects, insufficient. Based on these findings, the following recommendations are made: (1) expand the existing groundwater monitoring network to encompass all groundwater types, geological settings, and anthropogenic pressures in Rwanda; (2) install rainfall gauging stations at or near the groundwater monitoring stations to enhance the interpretation of groundwater monitoring data; (3) conduct groundwater sampling campaigns at least twice a year, that include major ion analyses; and (4) to regularly analyze and disseminate the monitoring results.