Snowy flushing flows

The Snowy River continues on the road to recovery with flushing flows improving the health of the waterway and enhancing habitat for local wildlife.

Snowy River environmental flows

Environmental flows are part of a plan to return the Snowy River to a smaller but healthier river.

Emma Wilson from the Department of Planning Industry and Environment said the flushing flows perform an important function for the river.

'The flushing flow coupled with high flow events help to clean and clear the river channel,' Ms Wilson said.

'For many years, the Snowy River carried only low flows from Jindabyne Dam that allowed sediment to settle and vegetation to grow and clog the river channel.

'The higher and more energetic flows clean and flush the spaces between gravel stones to improve productivity and habitat for aquatic animals.

'Environmental water is being managed to reintroduce daily flow variability including higher velocity 'flushing flows' that will help to restore the river's health.

'Environmental flows are released into the Snowy every day of the year. Over time, we expect these higher flows to more clearly define a channel pathway within the riverbed that can better support native wildlife, including water bugs, platypus, and frogs,' she said.

The most recent flushing flow occurred in October when water was released from Jindabyne Dam, providing a peak flow equivalent to 10,363 megalitres per hour for 8 hours. The Jindabyne Dam spillway gates were opened to deliver the flow. For other events, cone valves (large pipes) are utilised from the dam.

The daily flow pattern, and timing of higher releases during winter and spring, mimics the natural patterns typical of the mixed rainfall and snowmelt river systems in the Snowy Mountains.

The October event was the first flushing flow since 2018 due to dry conditions that reduced environmental allocations.

The management of flows is coordinated by the department's Water for the Environment team, in collaboration with DPIE Water and Snowy Hydro. A Stakeholder Advisory Committee provides input and endorses the approach.