How do we improve the ecological health of our rivers and at the same time encompass flood mitigation measures?
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Well the answer to this dilemma appears to be quite simple, make the rivers 'rough' again.
And what do we mean by rough - riverbanks should be vegetated and in some instances so should the in-stream channels.
"Rivers need their roughness back, they need to be messy," said Professor Kirstie Fryirs.
Prof. Fryirs was one of the guest speakers at the inaugural Hunter River Forum held in Singleton this week.
Organised and run by Hunter Local Land Services, the event was designed, to support local action to improve all the rivers in the Hunter catchment.
The theme of the gathering was improving the health and resilience of the Hunter River through community engagement in riparian management.
Riparian management has come to the fore following the 2021/22 floods which caused significant damage to waterways including the Hunter River and many of its tributaries.
There was extensive river and creekbank erosion throughout many coastal river catchments and in the case of the Hunter this impacted existing flood mitigation works and landholder access to irrigation infrastructure.
Among impacted landholders and communities there were arguments put forward that vegetation in fact impeded floodwaters causing higher and longer flood levels and therefore more damage.
By making rivers rough again we slow the water down, we lessen the erosive impacts of floods and best of all we initiate natural flood mitigation
- Professor Kirstie Fryirs
But that is a view rejected by researchers and academics in this field.
Asked whether riparian areas should be fenced off to exclude livestock and encourage regrowth Prof.Fryirs answered strongly in the affirmative.
"By making rivers rough again we slow the water down, we lessen the erosive impacts of floods and best of all we initiate natural flood mitigation," she said.
"How to achieve river roughness we must revegetate the riparian zone, the riverbanks and some in-stream channels.
"We need a messy, bendy river - really what it was like before we tried to engineer a river, we need to take it back to its natural state."
Prof Fryris from the School of Natural Sciences at Macquarie University studies the geomorphology or the process of how rivers function and river management.
She has received an Australian Research Council grant to study and implement natural flood management practices and part of that work will involve research on the Hunter River for the next four years.
Before white settlement the Hunter River was less straight and had far more vegetation throughout its catchment and riparian zones.
This changed as trees were cut down and channels straightened and deepened to make the river more navigable. These actions led to more erosion and the concentration of river flows in big channels.
"From the arrival of the first white settlers but particularly after the big floods mid last century we tried to engineer a flood free river," Prof. Fryirs said.
This view of the river being 'problematic' was also described by another speaker journalist and writer Scott Bevan, who this year published a book 'Return to the Hunter' , which covers his second kayaking journey down the Hunter River from Moonan Flat to Newcastle harbour.
What he found during his second journey was that nothing stands still or remains the same.
He said for 150 years our society has tried schemes and plans to control the river or really control mother nature.
Quoting a report from the 1870s which said 'rivers roused are indomitable' Mr Bevan told the Forum no matter what we do floods keep coming.
He went onto a quote a PhD student, Willow Forsyth, he met on his trip who was volunteering to assist with flood recovery, she said the river was not a curse it's what we do as humans to interact with the river that causes issues.
Despite the ongoing debate about river health and management for Prof. Fryirs the story of the Hunter River is not all doom and gloom, in fact she is optimistic that our interactions with the river since the 1980s are now starting to have positive outcomes.
"We basically took a new approach to river management from 1980s - which involved flood mitigation works to slow the flow and institute revegetation along riverbanks," she said.
"And this work is showing promising outcomes."
The best example of what this work has achieved was the slowing of flood peaks as they headed downstream.
In 1971 the flood peak took 17 hours to travel between Singleton and Maitland but thanks to works the same peak in July 2007 took 28 hours, she said.
"By slowing that flood peak you slow down its erosive potential. By re-greening river systems through better land management and work by Landcare you can bring about natural flood mitigation," she said.
"That is what we have to achieve as this also improves the health of out wetlands - so we are looking at catchment scale work to achieve natural flood mitigation."
Prof Fryirs quoted reports from 1890s and 1902 that said River Oaks protect the banks on which they grow.
"It was even suggested back then that it should be a penal offence to ringbark riverbank trees. So we have known what to do for a longtime," she said.
She called on the state government to act on its 2022 Flood Recover Inquiry in particular two recommendations. The first recommendation 20 : floodplains as assets and recommendation 27: environment.
As to the future Prof. Fryirs wants to see a truly messy Hunter River.