The Goulburn Broken Catchment Management Authority (GB CMA) is planning a water delivery for the environment, downstream of the Goulburn Weir in the Lower Goulburn River, from mid-July and into August 2022.
The Goulburn Broken Catchment Management Authority (GB CMA) is planning a water delivery for the environment, downstream of the Goulburn Weir in the Lower Goulburn River, from mid-July and into August 2022.
GB CMA environmental water and wetlands manager, Simon Casanelia, said the water release was referred to as a winter fresh.
“A fresh is flow that increases the height of the river for a short period of time,” Mr Casanelia said.
“This winter fresh will help maintain the health and functioning of the Goulburn River by depositing seed rich sediment on the banks which helps stabilising plants to grow, and moving sediments from the riverbed to maintain habitat for water bugs and native fish.
“It will also increase the habitat available for native fish, platypus and water bugs by inundating connected anabranches and wetlands.”
The fresh is planned to coincide with natural high flows where possible. If it is not possible to coincide with natural flows the fresh will peak in late July at up to 9500ML/day (a river height of 5.6m at Shepparton) before slowly dropping back to approximately 1000ML/day (a river height of 2.7m at Shepparton) in early-August. This is well below the minor flood level of 9.5m at Shepparton.
Mr Casanelia said the fresh aimed to utilise natural tributary inflows as much as possible, as they are rich in sediment and seed, instead of releases predominately from Lake Eildon.
“If there is heavy rain, environmental flow releases may be reduced or stopped,” he said.
“Releases of water for the environment are designed to mimic the natural flows that would have occurred before the river was dammed and regulated, although they are often much smaller than the flows that would have occurred naturally.”
The response of bank vegetation, bank condition, fish, stream metabolism and water bugs to the delivery of environmental water is assessed by the Commonwealth Environmental Water Office’s (CEWO) Lower Goulburn River Monitoring Evaluation and Research (Flow-MER) project: flow-mer.org.au/selected-area-lower-goulburn-river.
Environmental flows are planned by the Goulburn Broken CMA in consultation with the CEWO and the Victorian Environmental Water Holder (VEWH) as well as Goulburn-Murray Water, who manage the releases of environmental flows from its storages.
This use of water for the environment is authorised by the Victorian Environmental Water Holder in line with its Seasonal Watering Plan 2022-23, which is available for download from www.vewh.vic.gov.au, with regular watering updates posted on the Goulburn Broken CMA website
www.gbcma.vic.gov.auTiming of the environmental flows take into consideration delivery orders by irrigators and other water users and feedback from the community via the Goulburn Broken CMA’s environmental water advisory groups.
Providing water for the environment is only one way of protecting and improving rivers and wetlands. Fencing and revegetation, erosion control, pest control, returning logs to rivers (re-snagging) for fish and bug habitat, and installation of fishways to allow fish to pass through dams and weirs also help.
Find out more about river health, water for the environment and monitoring activities at
www.gbcma.vic.gov.auTo check flows in the Lower Goulburn, view the hydrograph on Goulburn Broken CMA’s website: fchmccoys.hydronet.com (updated weekly).
The Goulburn Broken CMA is planning a water delivery for the environment, downstream of the Goulburn Weir in the Lower Goulburn River, from mid-July and into August 2022.