The Goulburn Valley Environment Group remains concerned that the health of the Goulburn River is continuing to decline, arguing high summer flows were causing damage and undermining improvements gained by recent years’ environmental flows.
The group worries that recreational and tourism uses of the river too may suffer.
One fishing figure says if the ‘‘anatomy of the river’’ was compromised, the flow-on effect could undermine recreational uses of the Goulburn River.
A spokesperson from the Goulburn Broken Catchment Management Authority said flows were expected to range between 2000ML/day to 3000ML/day during the next few months.
‘‘As the flows are well above the recommended 800ML/day for this time of the year, GBCMA has asked the river operators to deliver the water as a series of pulses through the lower Goulburn River, rather than a steady flow, to help minimise damage to the river bank,’’ they said.
High unseasonal flows in the lower Goulburn River continued to be delivered to meet downstream water demands from towns, irrigators and the environment, the authority added.
GVEG has suggested a number of urgent actions, including implementing a maximum seasonal volume for flows through the Goulburn River.
‘‘There has to be a ceiling,’’ group president John Pettigrew said, adding action was urgent, pointing to recent years’ high flows.
Aside from the potential to undermine environmental benefits, Mr Pettigrew said river health and water quality would be first areas impacted.
‘‘The end result, if we let this grow and continue... we’ll lose that in-stream health, aquatic recreation will be affected.’’
Shepparton fishing industry stakeholder Steve Threlfall believed unseasonal high flows downstream that were prolonged for more than three weeks posed the most concern for river banks and habitat.
‘‘That constant high-level water flow has an effect on our vegetation,’’ Mr Threlfall said.
‘‘That bit just above the water... (it’s) now constantly at higher levels... for long periods and it’s killing it off.
‘‘That is the nursery for all good things that happen in the river. We have to have flows that peak and drop back to a natural level.’’
Mr Threlfall said he had observed sandbars under water during this summer period.
And while he said the higher water levels were yet to pose a serious impact on fishing — ‘‘it’s still fishing quite well’’ — he said it would pose a long-term effect on the anatomy of the river.
‘‘We can stock it (with fish)... but they rely on food sources, the environmental system to be able to have that grow out period,’’ he said.
‘‘It doesn’t help resident fish in their breeding cycles.’’
The GBCMA spokesperson said the authority was working with DELWP to understand and quantify potential environmental impacts of unseasonal river flows due to trade.
This includes additional monitoring this summer.
Last month, the GBCMA said additional funding and support was being explored to develop a new lower Goulburn River flows study and long-term environmental monitoring program to investigate the effects of unseasonal high flows on river banks, water quality, native fish and vegetation.
Mr Pettigrew welcomed recent ‘‘pulsing’’ of water as being all part of the broad answer.
Last year a holistic review into the impacts of running commercial water down the river in summer was endorsed as a resolution at the national conference of the Murray Darling Association.
Cr Dennis Patterson had at the time voiced concern longer periods of higher water in the Goulburn River were causing significant damage to river banks and habitat.
In calling for action to be taken, he and the council moved a motion at the MDA national conference that pushed for water ministers and water authorities to investigate environmental impacts of running commercial water down the Goulburn River during summer periods.
This came after the council argued he river had risen about 1.5m above its normal summer level last February, and stayed at this height for about two months, ‘‘destroying all the ground cover that had benefited from an environmental flow during spring 2017’’.
‘‘The river was artificially held high in these summer months due to the transfer of water to other irrigation areas following purchasing of this water, raising concerns about river bank erosion,’’ an argument to the conference read.