Integrated basin flow assessments: concepts and method development in Africa and South‐east Asia

Abstract

1. This study summarises our development and application in developing countries of a process for assessing the ecological, social and economic costs and benefits of waterresource developments, as an aid to basin planning. 2. During 15 years of work in Africa and Asia, the process sequentially included the whole river ecosystem and the whole flow regime in the assessment; used a multidisciplinary team and a scenario-based approach that gave equal weighting to the ecological, social, resource-economic and macro-economic costs and benefits of development; quantified or semi-quantified the costs and benefits in data-poor situations, capturing expert opinion and local wisdom as well as data; recognised that the final allocation of water for ecosystem maintenance should be a societal choice of trade-offs between resource protection and development. 3. Flow assessments were increasingly done at the basin rather than project level and introduced the concept and practicality of Development Space as a tool to aid basin planning. 4. Later assessments included valuation of regulating, cultural and provisioning services provided by rivers as part of the cost-benefit analysis. 5. Implementation of managed flows as outlined above is a complex and long-term process that should include a number of major steps, from development of the appropriate legislation to monitoring of management decisions and adaptive management. Country or region-wide implementation at this scale could well take one to two decades, even where the political will and technical skills exist. 6. We conclude by offering eight principles that we believe would promote genuinely sustainable use of rivers.

Accounting for environmental flow requirements in global water assessments

“…For example, the building block model is a well-documented method for estimating EFRs at either the local or basin scale (King and Louw, 1998;King and Brown, 2010;Tharme, 2003;Hugues and Rood, 2003). The building block method supports the principle that maintaining certain components of the natural flow is of fundamental importance.…”

The identification of hydrological indices for the characterization of macroinvertebrate community response to flow regime variability

“…Although most legislation relating to the management of water resources and the protection of the riverine environment does not explicitly use the term "environmental flows" or "e-flows," it is widely recognized that the delivery or maintenance of an appropriate flow regime is essential for the sustainable management of riverine ecosystems (Poff et al 2010, Shenton et al 2012. As a result, national guidelines and legislation are increasingly recognizing the need for river flow targets that reflect the competing demands on finite hydrological resources (Arthington et al 2006, Acreman and Ferguson 2010, King and Brown 2010, Peters et al 2012, Shenton et al 2012.…”

“…The majority of "environmental flows" research to date has focused on the assessment of different components of the flow regime and the extent to which these components potentially influence aquatic communities in North America (Richter et al 1996, Poff et al 1997, Armanini et al 2012, Europe (Monk et al 2006, 2008, Belmar et al 2013, southern Africa (King and Brown 2010) and Australia Thoms 2006, Leigh andSheldon 2009). These studies have subsequently been used to help define sustainable ecological/environmental flow regimes in regulated and anthropogenically modified rivers (Acreman et al 2008, Dunbar et al 2010b, Poff et al 2010, Peters et al 2012.…”

Human needs and environmental rights to water: a biocultural systems approach to hydrodevelopment and management

“…Arthington et al points to the increasing use of environmental flow assessments to modify water management regimes and restore the ecosystemic wealth of rivers and related fisheries as an important element in implementing the environmental flow concept (Arthington et al 2010, Poff et al 2010. Environmental flow assessment in the Lesotho Highlands Water Project, for example, documented and quantified the social and health impact of the loss of river resources for displaced communities in Lesotho and South Africa (e.g., food fishes, Arthington et al 2003), and these calculations were converted to compensation estimates for riparian people (King and Brown 2010).…”