Search crews located Peter’s submerged van at Evandale on Wednesday about 400 metres from where the Scottsdale man and his partner Karen Cassidy were swept away by floodwater on Tuesday morning.

Peter’s vest was also spotted, his family confirmed.

Peter – a contract delivery driver who resides at Riverside –  was delivering newspapers with Ms Cassidy when they were overcome by floodwater on Leighlands Road about 3am.

The couple climbed to the roof of the van, but were swept away after Peter had delivered his final wishes to his son Corey Watson.

Ms Cassidy was found downstream about 15 kilometres from where the incident happened with mild hypothermia, but Peter has not been located.

Corey said on Wednesday night that 15 family members would join four Tasmania Police officers during day three of the search.

“All of us think he’s still alive,” Corey said.

“It’s only been 38 hours.”

The boat will not be deployed unless weather permits.

If conditions allow, at least one tinny will be used to conduct searches from the Evandale Bridge down to Trevallyn Dam.

The family has sought advice from emergency services and did so again on Thursday morning.

The search is expected to resume about 8am.

Tasmania Police Sergeant Tony Roughan watched as Peter’s van was taken from the road.

"The water was moving very rapidly - the velocity of the water was really surprising."

The evidence of the flood's force was evident yesterday more of Leighlands Road was revealed.

Slabs of asphalt had been completely torn from the road as had several wooden posts that had been previously cemented deep into the ground.

Eighty-one-year-old Ouse man Trevor Foster is also still missing in the state’s South.

Police will continue to search for him on Thursday, but hold grave concerns for his wellbeing.