Police have named the man missing after he fell into the Hutt River on Sunday.
He is Uikilifi Peniamina, 49, from Upper Hutt.
Mr Peniamina was knocked overboard in rough waters on Sunday afternoon, near the rivermouth.
He was not wearing a lifejacket.
An extensive search of Wellington Harbour has failed to find any trace of him.
The Navy dive team will join the search for Mr Peniamina today, after flying down from Auckland by Hercules.
The team will use Remote Environmental Monitoring Unit (REMUS) sonar equipment to survey the sea floor.
Dive teams can then explore in greater detail.
It is expected that the Navy dive team survey will take up to two days.
''We appreciate the Navy assisting us in the search so that we can provide every reassurance to Mr Peniamina's family that everything was done to reunite them,'' senior sergeant Steve Harwood of Hutt Valley police said.
- The Dominion Post
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