Tamar Action Group says Tamar River's rice grass epidemic must be resolved

While many of these issues are common knowledge in the community, Tamar Action Group chair Andrew Lovitt says there is another major problem facing kanamaluka / River Tamar - rice grass.

Rice grass (Spartina anglica) was introduced in Australia in the 1920s. It was planted on the banks of the Tamar River estuary in 1947 by the CSIRO to make the estuary more habitable for larger ships and help stabilise the mudflats.

However, introducing rice grass had the opposite effect, narrowing the channel and exacerbating the sediment problem.

"The impacts of that decision have been far-reaching," Mr Lovitt said.

"The rice grass has taken root along the majority of the length of the estuary leading to one of the world's largest rice grass infestations.

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"More than 30 kilometres of the river is inundated with the grass, creating monocultures that exclude all other native plants, progressively squeezing our native flora and fauna."

The Tamar Action Group also says the rice grass infestation is progressively narrowing the river, creating faster tides and discouraging recreational boating.

"The issue of rice grass on the Tamar has been around for a long time, and it isn't going anywhere anytime soon," Mr Lovitt said.

"There are three ways rice grass can be eradicated.

"The 'approved for the purpose' herbicide to control rice grass is called Fusilade Forte. But although it is approved, using any poison is widely unpopular, especially on the scale that would be needed on the Tamar.

"Then, of course, the rice grass can be dug or dredged, either by hand or by machine, but both are very difficult and expensive.

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"The third way is an elegant and economical solution: Rice grass drowns in freshwater."

Mr Lovitt suggests the formation of a freshwater lake created by a barrage at Point Rapid near Rowella, a concept the Tamar Action Group calls 'Tamar Lake'.

"The economic benefits would be enormous," he said.

"The eradication of the rice grass would free up access to the river for other forms of boating, and the lake would be a mecca for freshwater fishing as it would be stocked in much the same way as the highland lakes.

"Freshwater for the proposed irrigation and hydrogen projects would be more economically available."

While the Tamar Action Group acknowledge that the construction of a barrage would be costly, they say that according to a feasibility study by an international consultant, there was no doubt the project would pay for itself.

"There are, of course, doubts and misinformation about a project to this size and scope," Mr Lovitt said.

"But this is when open discussion and frank scientific inquiry should be enacted."

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