Status and trends in EFlows in southern Africa

Abstract

Environmental Flows (EFlows) are defined as the quantity, timing and quality of the flow of water, sediment and biota necessary to sustain freshwater and estuarine ecosystems, and the human livelihoods and well‐being that depend on these ecosystems. As such they are a vital component of Integrated Water Resource Management (IWRM). A recent survey found that, in general, Africa lags behind schedule with respect to the global SDG Target 6.5 to implement IWRM at all levels, including through transboundary cooperation as appropriate. This web‐based review explores progress made in EFlows Assessments and implementing their outcomes in southern Africa. It outlines the apparent impetus to the uptake of EFlows provided by legislation, common funding mechanisms for EFlows assessment and evolving trends in EFlows assessment. It also highlights instances of implementation of EFlows in both in‐country and transboundary settings.

Farm Dams in Southern Africa: Balancing Environmental and Socio-Economic Sustainability

“…While the choice of which model to use may depend on a number of factors (including user preference and experience), it is clearly important that the model includes components that simulate all the main anthropogenic impacts, including large dams and smaller farm dams [16,17]. Many countries of southern Africa have some form of policy and legislation that regulates water use to ensure a defined level of protection for aquatic ecosystems, and methods have been developed to undertake the necessary assessments [41][42][43] and generate information that is compatible with integrated water resources yield models [44,45]. The lower part of the diagram represents the main decision-making part of the whole process where various scenarios can be considered in the context of the requirements and attitudes of the full range of stakeholders.…”

Advancing the Science of Environmental Flow Management for Protection of Temporarily Closed Estuaries and Coastal Lagoons

“…Establishing robust methods for trade-offs between competing values is an important step towards establishing a consensus around desired outcomes. Brown et al [114,115] describe two approaches to determining desired outcomes-prescriptive vs. scenario based. In a prescriptive approach, there is an agreed level of ecological condition that must be maintained, and a flow regime is prescribed to support this.…”

Ten Principles to Determine Environmental Flow Requirements for Temporarily Closed Estuaries

“…These EFlows support human cultures, economies, sustainable livelihoods, and well-being [28]. EFlow requirements were seldom considered in water resource planning and management [29][30][31][32][33] until methods were developed for estuaries in South Africa, Australia, and the USA (CA and TX) [33,34]. EFlow requirements have also been described for Mediterranean coastal ecosystems, such as the Ebro Delta, where anthropogenic pressures are magnified by the natural hydrological variability of aquatic ecosystems [35,36].…”

“…This necessitates a holistic catchment-to-coast management approach that requires collaboration across government departments and sectors (Figure 12b). The Integrated Water Resource Management (IWRM) process captures some of this complexity and EFlows are an important component [30]. Estuaries are subjected to multiple pressures, e.g., artificial breaching and biological invasions [7], and need to be assessed as part of an estuary EFlow assessment to ensure that desired state objectives are achievable.…”