Tamar River health could be fixed by a barrage

Tamar Lake near Royal Park and the marina.
Tamar Lake near Royal Park and the marina.

A seven-year investigation aimed at improving the health of the Tamar Lake has found a $320 million barrage development would increase Launceston’s property values.

Produced by the executive and members of Tamar Lake Incorporated, the study began in 2010 with a view to improving the health, economic and amenity benefits.

More than $500,000 was spent on consultants and hundreds of hours of volunteer work was contributed.

The study found with a barrage installed at the south end of Long Reach, a large, constant-level freshwater reservoir 80 per cent the size of Sydney Harbour would form behind the barrage.

According to the report, a large reservoir would change the tidal action in the upper reaches; “greatly enhancing the quality of water upstream of the barrage and generally improving the use and amenity of the upper Tamar”.

With the barrage, no new silt accumulation will occur and the residual silt bed would erode with each major flood event.

The Tamar Lake report claims the muddy water appearance in the upper Tamar River would transition within 12 months to the same clear water clarity as the Trevallyn Lake. 

It is estimated the total cost of the project, including land acquisitions, consultants and construction of a barrage would cost about $320 million.

Tamar Lake Incorporated president, Sam Tucker, said the report appeared “to resolve a lot of the issues of the Tamar”.

“The feasibility report shows this is a genuinely viable alternative to fix a multiple of issues to do with the health of the Tamar River,” he said. 

“This is a project that should be further investigated.”

Mr Tucker said the feasibility report laid the groundwork for a business case and environmental impact study to follow.

“The feasibility study was about uncovering any uncover any fatal flaws,” he said.

Mr Tucker said there were unanswered questions that still needed answering.

The report argues the “benefits to property values alone from the project greatly exceed its costs” – with a healthy river resulting in an uplift in median residential property values within one kilometre of the Tamar Lake shoreline.

By building the barrage and changing tidal flow there would be some displacement of natural ecological values, but no listed species would be threatened and freshwater habitats – including the Tamar Island Wetlands – “would be greatly expanded”.

The Tamar Lake Incorporated report was submitted to the Tamar Estuary Management Taskforce – a government-driven group established in July to investigate the river’s health.