Narrow Results

The concept of environmental water requirements (EWRs) is central to Australia’s present approach to water reform. Current decision-making regarding environmental water relies strongly on the notion that EWRs necessary to meet targets associated with ecological objectives for asset sites can be scientifically defined, thus enabling the ecological outcomes of alternative water management scenarios to be evaluated in a relatively straightforward fashion in relation to these flow thresholds or targets. We argue, however, that the ecological objectives and targets currently underpinning the development of EWRs in the Murray-Darling Basin are insufficient to permit the identification of exact water requirements or flow thresholds. Because of the dynamic and heterogeneous nature of the Murray-Darling Basin and the myriad ways in which it is valued by people, we also assert that it is unlikely that adequate ecological objectives and targets from which to determine EWRs could ever be formulated. We suggest that the current emphasis on the concept of EWRs in environmental water planning conflates science and values, perpetuating a “how much is enough?” myth whereby the significance of the social, cultural and political dimension in environmental decision-making is diminished. We support an alternative paradigm in which the contribution of ecological science to water policy and management decisions focuses on understanding ecological responses of water-dependent ecosystems and their biota to alternative management scenarios and linking these responses to the ecosystem services and human values which they support.

There are over 300 transboundary surface water basins worldwide and more than 450 known transboundary aquifer systems. Each of these has the potential for conflict if not managed properly. International water agreements can promote regional peace and security and encourage economic growth; however, states must account for their current and future uses within the natural ecosystem to ensure the best use of the water. Water divisions are often numerical and motivated by politics. With few advocates for specific water allocations for flora and fauna, nature can be entirely omitted from international water agreements and, if included, is often not addressed directly. Neglecting to include environmental considerations is harmful to the environment and can threaten the sustainability of participating states. Economic success and social sustainability are intricately tied to natural systems. Failure to consider ecosystem and watershed dynamics can undermine a shared use agreement and the communities it is meant to assist. This chapter advocates for the inclusion of environmental flow provisions in international water treaties and agreements. Inclusion of explicit environmental flow provisions better represents the economic and human health-related aspects related to existing ecosystems. To support this premise, this chapter reviews the history of international water law and existing international agreements to demonstrate that the environment has taken a backseat to water delivery obligations. This chapter also presents the science of environmental flows and the benefits ecosystem services can provide for the participating states. International water law, international law, and domestic laws are cited to provide precedent and guidance for how water should be expressly set aside for nature. Finally, this chapter proposes some specific parameters that should be included in international water negotiations to better capture environmental factors.

Environmental flows (EFs) describe the quantity, timing, and quality of water flows required to sustain freshwater and estuarine ecosystems and the human livelihoods and well-being that depend on these ecosystems. The EFs include hydrological processes, hydrodynamic factors, water chemical elements and ecological goals. EFs was studied beginning in river minimum flow, researches focused from a single flow to hydrological processes that meeting river ecological demands. The concept and methods of EFs were improved continuously. Brisbane conference in 2007 was a milestone for EFs research. Effect mechanism of EFs on river ecosystem mainly reflected in the congruent relationship between EFs components and river ecological processes. The types of EFs methodologies mainly include hydrological, hydraulic, habitat simulation, holistic and other methods. To achieve environmental flows management (EFM), the river ecological monitoring is the basic need, and the ecological scheduling is a way to manage river from water quantity and timing, as well as total quantity control of pollutant discharge is an important approach to achieve water quality management. With the development of research and practices, basic research of EFs still need to be strengthened, the management framework and strategy will be the trend in EFs further research, and EFM will become an important part in river management.