To subscribe for email updates from eWater, please enter your details below.
"Those who are quick to criticise how our rivers and waterways are managed should try filling an environmental water manager’s shoes...
...Consider the case of River Red gums, which grow along the banks of Australian waterways, provide vital habitat to wildlife, and have huge cultural significance for our Indigenous people. eWater and partner organisations tested the likely consequences of delivering environmental flows to Red Gum forests on the River Murray in northern Victoria.
Water managers understand how great a percentage of southern Australia’s biodiversity is found along these rivers and floodplains, and that many of these habitats are at real risk of dying. It’s a given that they consider environment needs when contemplating water allocations. However, they can’t effectively resolve water allocation problems without fully understanding all of the issues involved. Often times these issues concern a range of stakeholders with conflicting agendas.
Environmental water managers have to juggle a wide array of conflicting environmental, social and economic demands upon the water and environments they manage. Competing stakeholders clamor for a share as the water manager struggles to ensure adequate water remains in the system to secure environmental health.
To effectively manage water, the water manager must have a sound knowledge of the science underpinning groundwater, rivers, wetlands, catchments and floodplains and how these interact; consider all of the demands of the competing stakeholders, and then determine the best timing, quantity and duration of environmental flows to also ensure water quality is maintained.
As a limited and precious resource, water must be managed for both immediate needs and for long-term economic and environmental sustainability.
How do river managers decide exactly how much water is needed and when? They must prioritise while competing users cry out for an increased share of the water. Fortunately for water managers, stakeholders and the environment, eWater now has a range of software ‘ecotools’ designed to make such decisions easier.
Concept, Eco Modeller, and eFlow Predictor comprise a suite of free ecotools that can simplify the life of the river manager. Until they became available there were few tools to explore the likely water cost of reinstating flow regimes.
In the case of the River Red Gum, how do you balance the needs of all those calling out for a water allocation against protection of the environment? The Concept program paves the way by allowing the water managers to create a dynamic diagram of an environmental system with the key components represented as simple icons.
The power behind this tool lies in its ability to not only represent all the important components of a system but also the relationships between them. Once the manager has all the elements and their relationships in place, they can better understand how changing a relationship alters the condition of all the related components. Bringing stakeholders with conflicting agendas together can often times be a daunting exercise resulting in no clear consensus on a way forward. Using Concept each stakeholder can present a case for the importance of various parts of the system and their linkages. The group can then test the relationships and immediately build a consensus on how a system works and how critical components should to be managed.
The tool was developed to help the water manager, stakeholders and expert panel members visualise an environment and draw out the ecological dynamics for discussion. Ideal for communicating ideas, building consensus, and deciding on priorities, it is a whiteboard par excellence.
The water manager benefits over using a standard whiteboard or traditional static conceptual diagram by being able to clearly see how the ‘health’ of environmental icons changes as the condition of other icons is varied. A ‘health bar’ underneath each icon indicates how the condition of that element is responding to changes made elsewhere in the dynamic diagram.
The Concept tool helps the Environmental Water Manager better understand and take account of the broader stakeholder interests and their likely response to watering decisions. With the problem fully defined and understood the next step is to facilitate management decisions by quantifying the ecological consequences of alternative water use scenarios.
Eco Modeller makes it easy to pose (and answer) ‘what if’ questions for a range of natural resource management activities. Using Eco Modeller river managers can calculate — transparently and in a repeatable manner — how a wetland may respond to watering in summer or whether a fish population may benefit from that same volume of water being retained within the channel.
Eco Modeller applies ecological response models to entered time series data such as flow and snag density over time. Once the river manager chooses an appropriate model, Eco Modeller runs the data and produces summary results of the predicted ecological response. It can run many different computational forms of models and compare their outputs.
A key feature of Eco Modeller is its internal library with its store of ecological models relevant to the situation at hand. The user links their data to a particular management scenario — for example, the effects of flow on fish sustainability — and the software predicts how the fish habitat will change over time in response to management actions captured in the input scenario.
The software captures provenance information for each model added to the library. This produces a confidence score for each ecological model, making this tool much more than a collection of equations. The model confidence is based on factors that traditionally support good science, including the quality of the publication where the information was published, the extent of the data underlying the model, and supporting documentation. It also takes into account the geographic area to which the model applies, the renown of the author, and documented limitations.
Better still, Eco Modeller can be used to explore the effects of any environmental change.
For instance the Eco Modeller library shows that mature River Red Gums thrive when their river is flooded for anywhere between one to five months at a time, and suffer badly when floods extend for any longer than two years. They do better when flooding occurs in the second half of the year, and are happiest when the period between floods is less than five years. Seedlings succeed best when floods occur in September, October and November, but the time between floods is immaterial because the seed bank enjoys great longevity.
Backed by this knowledge the environmental water manager could, for instance, compare what might happen to the Red Gum’s habitat under two model scenarios: one where no water is extracted from the river for consumption (all consumptive use turned off for entire period) and one where current levels of water abstracted from the river and hence no longer available for use are maintained (current consumptive use turned on for entire period).
The final step for the water manager is to compare various management scenarios and design e-flows to suit, starting with new flow scenarios created by modelling increased flow to specific parts of the hydrograph.
eFlow Predictor makes it simple for the water manager to discover what impact increasing flood frequency would have on those River Red Gums.
For many catchments, the river environments’ water requirements are based on the recommendations of expert panels detailing a range of flow components needed to satisfy a variety of individual flow targets.
eFlow Predictor is a standalone scenario testing tool that can help the panel or river manager to calculate the amounts of water required to provide flows that meet a set of environmental needs, and the associated water cost.
The software lets the water manager understand the water volumes, day by day, needed to achieve the recommended environmental flows and clearly sets out the calculated volumes involved.
Using eFlow Predictor the environmental water manager could predict the volumes that will preserve the health of the Red Gums, by objectively comparing the flows needed for environmental and human uses from the same river. Possible tradeoffs can be seen and planned for.
eFlow Predictor helps in areas like the Murray–Darling Basin, where water is tightly regulated, and almost every mega litre of water passes through a dam, weir or irrigation structure. With strong tensions between water use for consumption (irrigation and urban demand) and for environmental benefits, river managers must clearly demonstrate the advantages of allowing water to run free. This is especially the case in drought years, where the amount of water is severely limited.
Click on one of the stars below to rate this article from 1 (lowest) to 5 (highest).