Coastal areas of Kenya (Kilifi County), Tanzania (Kilwa district) and Comoros (Ngazidja island), East Africa.
Research aimed to understand the physical and societal drivers of groundwater accessibility and identify critical aspects of groundwater access and knowledge gaps that require further monitoring and research. Interdisciplinary societal, environmental and hydrogeological investigations were consistently undertaken in the three areas considered as exemplars of the diversity of the coastal fringes of the wider region. This paper focuses on the hydrogeological outcomes of the research, framed within the principal socio-environmental issues identified.
New hydrological insights
Results confirm the fundamental importance of coastal groundwater resources for the development of the region and the urgent need to match groundwater development with demographic and economic growth. Hydrogeological knowledge is fragmented, groundwater lacks a long-term monitoring infrastructure and information transfer from stakeholders to users is limited. Current trends in demography, climate, sea-level and land-use are further threatening freshwater availability. Despite possessing high-productivity aquifers, water quality from wells and boreholes is generally impacted by saltwater intrusion. Shallow large-diameter wells, following the traditional model of these areas, consistently prove to be less saline and more durable than deeper small-diameter boreholes. However, promoting the use of large numbers of shallow wells poses a significant challenge for governance, requiring coherent management of the resource at local and national scales and the engagement of local communities.
This research was funded by the UK Natural Environment Research Council NERC, the Department for International Development DFID-UKAID, the Economic and Social Research Council ESRC; UPGRO Grant No NE/L001888/1: towards groundwater security in coastal East Africa. Geophysical data acquisition in the Comoros was funded by the French Development Agency AFD: project GECEAU CKM1068. We acknowledge stakeholders and community members from Grande Comore, Kilwa district and Kilifi Region for their active and fruitful participation in the focussed group discussions and questionnaire surveys. We are grateful to Bonventure Obeka and Stanley Wanjala (MA Sociology students at Pwani University) for assistance throughout the project, to postgraduate and undergraduate students from the Universities of the Comoros, Dar Es Salaam, Pwani and Kenyatta and interns from the Comoros Water Directorate DGEME for assistance in field data acquisition. We thank Isaac Marobhe (University of Dar Es Salaam) for assistance and the loan of field equipment, as well as Peter Karanja Gathu (Kilifi District Water Agency), Magai Kakuru (Kilwa District Water Department), Mahabadi Boinali (Comoros Water Directorate DGEME), Youssouf Ben Abdallah (Comoros Community Representative CIGEO) and Simon Onywere (Kenyatta University) for contributions to the final workshop discussions. We also acknowledge the assistance of the British Institute in Eastern Africa (BIEA) and particularly the late Joseph Mutua for his technical and logistical expertise and untiring assistance through fieldwork in Tanzania and Kenya. We are finally grateful to the Reviewers and Editorial Board of the journal for their valuable comments and suggestions that helped improving the quality of the manuscript.
- coastal aquifer
- Eastern Africa
- environmental change
- community engagement