1 Introduction

This book describes the development of Managed Aquifer Recharge (MAR) practices in South Africa. Examples from Namibia are included because the territory (South West Africa) was administered by South Africa until its independence in 1990. Various case studies are used to contrast different environments, the MAR technologies chosen and the results achieved. A concluding assessment is provided regarding its uptake and integration to date into broader country water resource management policies and practices.

Poverty is the dominant development issue in Sub-Saharan Africa and lack of access to clean water is a key cause of poverty. And yet to date, the region has used only a small portion (5 percent) of its available water resources. The African water crisis, as it is often referred to in international forums, is much more complex than water availability. The complicating factors include: the large spatial and temporal variation of resource availability; the arid climate prevalent in about 60 percent of the African continent; and the widespread lack of skilled and experienced human resources to manage the irregular availability of water. Such needed skills include building and balancing water storage, transferring water between water-rich and water-poor areas, and implementing programs to manage water demand and conservation (Braune and Xu, 2008).

Groundwater is the critical underlying resource for human survival and economic development in extensive drought-prone areas across Sub-Saharan Africa. The accessibility of groundwater in traditional shallow hand-dug wells, springs and seepage areas has always controlled the extent of human settlement beyond the major riparian tracts. The widespread introduction of drill rigs and water-well pumps in the 1970s enabled further extension of human activity. Today the dependence of rural water supply on groundwater is indisputable, with successful water wells allowing for functioning villages, clinics, schools, markets and livestock posts over large areas.

In recent years demand for urban water-supply provision has been increasing at a range of scales – from improving water services in innumerable small (but rapidly expanding) towns to supplementary public and private water-supply sources in larger cities. Also, groundwater use for irrigation is forecast to increase substantially – both for high-value crop production at the commercial scale, and for subsistence horticulture and drought-proofing staple-crop cultivation (Foster et al., 2012).

In contrast to its strategic role as an essential resource to help achieve community development and poverty alleviation in Southern Africa and more widely, groundwater has remained a poorly understood and poorly managed resource (Braune et al., 2008). Groundwater aquifers that supply many African mega cities are often heavily polluted (e.g., Dakar, Abidjan, Lagos, Accra, Lomé, Lusaka, Addis Ababa). Groundwater subjected to unplanned and excessive abstraction (pumping of water from the subsurface) in coastal cities is inducing salt water intrusion resulting in permanent damage to coastal aquifers (Xu and Usher, 2006). Data on groundwater systems are sparse and the current state of knowledge is low. Efforts to improve the situation have been made over the last decade through the publication of syntheses and reviews at the national, regional, and continental levels. MacDonald and others (2012) produced the first quantitative maps of groundwater resources for Africa as a whole. These maps indicate that groundwater storage is typically one to two magnitudes less in Sub-Saharan Africa than in North Africa.

Provision of sufficient storage capacity under growing water demand and increasing climate variability is one the main concerns for water managers in the region in the coming decades. While accurate estimates for required storage capacity do not exist, it is expected that, in five to ten years some multiple of the present storage capacity will be needed to provide sufficient water during dry periods. Importantly for arid areas, water stored in an aquifer is not subject to the same evaporative water losses as water stored in surface reservoirs behind dams, Evaporative losses can be significant depending on dam location and reservoir surface area. The natural storage (water buffer) available in aquifers makes conjunctive use of surface and groundwater particularly attractive and provides a pressing need for investment in drought preparedness at a variety of scales. Investment is required for enhanced management of groundwater storage, including managed aquifer recharge, to buffer drought impacts (Van Steenbergen and Tuinhof, 2009; Tuinhof et al., 2011).

Managed aquifer recharge is not a new concept in Southern Africa. Nearly 40 years ago, the prospect of storing treated sewage water in the sand beds of the Cape Flats in South Africa led the Water Research Commission to fund research in this regard (DWAF, 2010). The Atlantis scheme near Cape Town has been operational for more than 40 years. MAR has been shown to have a range of benefits, particularly if practiced as part of a wider approach to water resource management, and there is growing recognition that MAR often provides the cheapest form of new safe water supply for towns and small communities. Nonetheless, uptake of MAR into practice has remained limited in Sub-Saharan Africa. At a technical level this can be ascribed to a lack of understanding of hydrogeology and/or knowledge of MAR, but at a broad level it can be related to the slow or absent reform of the institutional framework for groundwater governance (Gale, 2005; Foster et al., 2012). This is discussed further in Section 10, Conclusions.

Managed aquifer recharge has gradually replaced the term artificial recharge to emphasize the recharge as a managed process. The term artificial recharge is still used in regulations and guidelines in Southern Africa, and we use the two terms interchangeably in this book.


Managed Aquifer Recharge: Southern Africa Copyright © 2021 by Eberhard Braune and Sumaya Israel. All Rights Reserved.