When David Maynard looks over the mudbanks along the upper kanamaluka/Tamar, he doesn't see a blight on the landscape.
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He sees a complex part of the estuary's tidal ecosystem.
"The mud is not broken, mud doesn't need fixing, it's natural," Mr Maynard said.
"What we need to do is look at how we live with that, how we change how we value it, if we were to let it re-establish.
"If we would have improved wetlands, emergent forests of ti trees and such around, maybe we could encourage more recreational activities around those wetlands."
As natural sciences curator at the Queen Victoria Museum and Art Gallery, he encourages Launceston residents to visit the Tamar estuary exhibit in the Inveresk museum where the waterway's history, its science and its various ecosystems are explained in great detail.
While the re-emergent mudbanks have become the focus of public debate over the state of the Tamar, Mr Maynard said this is another symptom of a problem that plagues scientific discussion about marine environments: that is, humans can only see what goes on above the surface.
His underwater photography shows the diverse sponge gardens, algaes on rocky reefs and giant kelp beneath the surface of the lower Tamar, as well as the marine life that relies upon these.
Mr Maynard said the practice of raking had flow-on effects that harmed these ecosystems many kilometres closer to the sea, reducing water quality for both natural systems and for aquaculture.
And the mud itself was also crucial to sustaining endangered wildlife.
"The soft sediment habitats are a habitat in themselves," Mr Maynard said.
"If you go down just down the West Tamar and you've got the Tamar Island wetlands reserve and their wetlands are celebrated. You've got boardwalks that take you out across mud flats, where you can see migratory birds, wading birds, it's a reservoir, it's a protected spot for a lot of threatened, endangered and protected species.
"But then the sediment itself, below the surface, is home to a lot of fauna that live on it, and live in it.
"Every time we disturb it, you ruin that habitat. And so that's where you get this misconception that it's just mud and nothing lives there. If you leave it long enough, it will become important habitat in itself and it will provide for other species."
The kanamaluka/Tamar has a rich history. When humans first crossed the land bridge between Victoria and Tasmania 42,000 years ago, the Tamar Valley likely stretched hundreds of kilometres into Bass Strait as a river. As the Ice Age finished and waters rose, it was inundated with seawater and became a tidal estuary.
Expansive mudflats started to dominate its upper reaches, even with the South and North Esk rivers in their natural states, before human intervention when dams and suburbs restricted the flow of water.
Mr Maynard said the flow of these rivers would never be enough to "flush" the sediment out to sea, aside from periodic flood events when sediment levels could be reduced.
"We know that from when they were silt raking, there were studies around what's in it, where's it going, what happens when it gets there," he said.
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"So what's in it? We know a lot of heavy metals. Where's it go? Well, nearly all of it goes straight back up to Launceston and to the North Esk River."
The construction of a dam on the South Esk and reduced flows on the North Esk due to development were unlikely to have made a difference to mud build-up, Mr Maynard believed, based on images of the Tamar pre-development that showed expansive mudflats in its natural state.
This view is contested, however, including by former Launceston Flood Authority chairman Alan Birchmore who has long argued for natural flows to be restored to the South Esk to "carry out the historic task of flushing and cleansing the First Basin, Yacht Basin, Seaport and Silo Home Reach".
This would involve closing the diversion at Trevallyn power station.
Following the release of a report from the City of Launceston which resulted in the banning of raking on environmental and cost-effectiveness grounds, Mr Birchmore - through his correspondence with The Examiner - argued that two-and-a-half times more sediment was removed using raking and South Esk spills, compared with no raking.
"Raking conducted with flexible rules delivers a better silt management strategy than any alternative," he said in 2019, also arguing that it reduced the severity of floods in Launceston.
With the Tamar Estuary Management Taskforce to soon release a report into options for the ongoing management of the estuary, the debate is likely to be reignited once again.