• Stable Water ClusterForming a Double Helix

  • Stable Water ClusterForming a Double Helix 1

Water for the environment has been a part of policy in Victoria since the 1990s. It’s water managed to maintain the health of rivers and wetlands. Although it refers to any water in our waterways that’s good for the environment, we are concerned with water held under environmental entitlements.

What is water for the environment?

The environment: Clean water is life, health, food, leisure and energy
Though water for the environment can mean any water in a river or wetland that benefits the environment, when we talk about ‘water for the environment’ (or ‘environmental water’) we are referring to water that’s set aside in storages such as reservoirs and dams which is managed for plants and animals. Many of Victoria’s river systems have been modified as the state has prospered and population grown, to provide water important for towns, industry and food production. Instead of water flowing naturally through the landscape, water is now captured in dams and weirs, and then delivered via pipes and man-made channels. As a result, some of our rivers give up more than a third – and sometimes half – of the water that would have naturally flowed in them throughout each year.

Changing flows

Environment | We believe that a sustainable future is possible
Instead of flowing naturally, with high flows in winter and low flows in the hotter months of summer, rivers now run higher when water needs to be delivered for farming and urban use. These changes have interrupted many of the natural river and wetland processes needed by native plants and animals to survive, feed and breed. Water for the environment is released into some of these rivers and wetlands to improve their health and protect environmental values. In rivers, water for the environment can be delivered to mimic some of the flows that would have occurred naturally before rivers were modified.
Water for the environment does not try to return rivers and wetlands to their pre-European condition. Many rivers and wetlands are so modified that this is not feasible; however environmental watering can help to minimize some of the impacts of these modifications on rivers and wetlands. Managers of water for the environment generally focus on returning some of the small and medium-sized rivers flows important in the life cycles of native plants and animals. In wetlands, water for the environment is focused on mimicking some of the natural wetting and drying cycles that plants and animals depend on for their diversity and long-term resilience.

Types of flows

A typical natural flow pattern of a victorian river, before the construction of dams, weirs and channels
It’s not simply the amount of water flowing in a river that’s important. It’s the entire environmental flow regime that matters, including the volume, timing, duration, frequency and quality of flows that are provided. Like the natural flow of rivers, different combinations of these provide a range of benefits for ecosystems. Releasing small amounts of water, called ‘freshes’, through summer helps to maintain or improve water quality. Flooding in spring replenishes a river channel and provides soil and nutrients for floodplains, as well as being vital for waterbirds and native fish to breed.