Farms, Rivers & Markets: A whole of system approach to doing more with less - M/BUS/296
Environmental water requirements are often treated as a fixed constraint on water resource planning and operation. Indeed the environmental water “requirement” routinely exceeds that which is available for the environment. This means either the constraint is revised and applied in some diminished form or ignored entirely. One objective of the Farms Rivers Markets Project is to lead a shift from treating environmental water use as a constraint on delivery for consumptive users to water resource planning for achievement of ecological and consumptive targets. In other words, we wish to treat environmental demands in an equivalent way to competing human water demands where priorities, trade-offs and synergies are explicitly identified. This applies whether outcomes are achieved through water management or market-based mechanisms. Inside this challenge is the goal of identifying water systems, which deliver more, both in terms of consumptive and environmental outcomes. Establishing environmental water targets is important for achieving this research goal. Consumptive users can quite clearly state their desired watering regime and evaluate consequences of alternate water allocations. In contrast the environmental demands are often poorly expressed in current practice, even to the extent of not being able to define the water required to avoid catastrophic collapse. This paper discusses some of the challenges we face in articulating these environmental demands as targets and informing trade-off decisions. The structure is described as follows. 1.-It begins with a discussion of “ecological targets”. These are the ecological equivalents to targets of maximizing regional production from irrigation or profit for individual producers. Ecological targets relate to the desired outcomes in terms of ecosystem change. 2.-The second section deals with environmental water targets, which are the desired watering regimes to achieve the ecological targets. There has been an emphasis on natural flow variability in environmental water regimes. There is a particular opportunity for benefiting environmental and consumptive water uses in terms of delivery of a sequence of environmental water regimes with different volumes required in different years to achieve long-term outcomes. Questions of dynamics and risk related to this concept are discussed in the second section. 3.-A core challenge of improving the efficiency of environmental water management is a substantial lack of knowledge around environmental responses to watering decisions. This is true both in terms of predicting consequences of proposed actions or evaluating past watering actions. If we are to improve the efficiency of environmental water delivery than we must radically improve our knowledge-base and the way we use it to inform environmental watering decisions. The third section discusses this challenge 4.-A final challenge is how to express ecological outcomes in terms which can be evaluated in a water resource planning context. The challenge here is the ecosystem outcomes are (i) in terms of multiple ecosystems responses; (ii) at multiple spatial and temporal scale; and (iii) with a high degree of uncertainty. The fourth section provides a very brief discussion on this issue. 5.-The final section describes how the Ecology Component of Farms Rivers Markets is tackling some of these issues.
MDFRC funding agency: The University of Melbourne
MDFRC client: The University of Melbourne
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Copyright (2010) Murray-Darling Freshwater Research Centre.