Triple whammy for Tas dairy farmers

It's been a trio of hard knocks this year for dairy farmers like Kem Perkins in northwest Tasmania.

The river flats around the township of Latrobe, south of Devonport, are among the most productive dairy farmland in the nation.

But 2016 has not been kind to dairy farmers there.

First up, the Mersey River stopped flowing in January after a record drought.

Then the raw milk price crisis hit, sending many into a debt spiral.

Now farmers are grappling with livestock losses, destroyed paddocks, damaged machinery, sheds and irrigation pumps from this week's storms and floods.

Prime Minister Malcolm Turnbull heard about their plight during a closed-door meeting with farmers in Latrobe on Thursday, before announcing disaster relief arrangements for flooded residents, businesses, farmers and community groups.

Mr Perkins, who turns 86 next week, fears the floods will push some of the region's farmers over the edge.

"Morale will be well down after this. Farmers with a debt load will find it extremely difficult," he told AAP.

He lost 55 dairy heifers in the raging torrent. Others nearby sustained losses in the hundreds.

A neighbour had had to rush 200 jersey cows over to Mr Perkins' property for safekeeping and milking.

The biggest problems facing farmers in the aftermath were a lack of fodder and flattened fences, Mr Perkins said.

In town, the home of elderly residents Gloria and Keith Reeves is waterlogged but they managed to escape unscathed.

Another elderly Latrobe resident died in the floods.

"I couldn't have walked through it on my own," Mr Reeves told AAP outside the community recovery centre.

"We had women each side of us helping us through the water."

The keen gardener is upset the floods destroyed his hothouse of multicoloured begonias.

Mr Reeves, 88, said it would be tough starting over at his age.

But he's a third-time flood victim.

His milk bar was inundated with water in 1973 and in 1977 his home flooded.

Mr Turnbull earlier on Thursday marvelled at the sheer force of the foaming Tamar River at Launceston.

The regional city was on the brink of catastrophe when the river peaked twice on Wednesday but a $58 million new flood levee proved a saviour.

At its peak the river was flowing at the equivalent volume of 2500 ute trucks per second up from its usual two.

Mr Turnbull returned to Sydney on Thursday afternoon to deliver a foreign policy speech.