The Launceston City Council will stop contributing to dredging 30,000 cubic metres of silt in the basin from July - after declaring the problem stemmed from outside its municipal boundary.

Premier David Bartlett said he had been committed to the river since his $250,000 budget contribution to the council's silt study, made on his second day in office.

He said the Government would provide an extra $11.5 million to upgrade levees and an extra $6.65 million over three years for a major dredging program.

"We will continue to support the Tamar and Esk River Program, which Labor established, to be boosted by $350,000 a year in additional funding ... for strategic planning and partnership arrangements for the catchment area that can genuinely manage this issue for the long term," Mr Bartlett said.

Liberal leader Will Hodgman said the asset was a key to unlocking the city's appeal for tourists and recreational activity.

On top of another $11.5 million for the levee upgrade, the Liberals have committed $9.5 million to address the silt problem and establish a single statutory authority to oversee the dredging program recommended by GHD - removing an estimated 150,000 cubic metres of silt in the first year, followed by 50,000 cubic metres each year afterwards.

"Importantly we do need to address the causes and that is why the new authority would be required to produce a strategic catchment management plan for better Tamar management," Mr Hodgman said.

Mr McKim said that clear felling needed to be stopped in the upper catchment to fix the silt problem.

He said the establishment of a Tamar and Esk Catchment Management Authority would look at all activities in the upper reaches, not only forestry and silt issues.

"This would be a whole-of- catchment management authority that would actually have the teeth to deliver the health of the Tamar that Launcestonians deserve," he said,

The Greens have also announced $11.5 million for urgent restoration work on the levees.