Police are hoping a spell of bad weather will uncover the body of Canadian tourist Connor Hayes.
Hokitika police Sergeant Russell Glue said police were waiting for the Haast River level to rise and potentially dislodge Mr Hayes' body, or wild seas to return his body to land.
Whitebaiters and tourism operators were also being asked to keep an eye out, he said.
"Obviously down there there's whitebaiters down all sides of the Haast River and all the other rivers as well, so there's a lot of them around at the moment. That's helping our cause.
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"There's [also] a local jet boat company that runs a tourism venture down there so he's also keeping an eye out on the Haast River, and there's also all the helicopter operators as well."
The local Haast police constable has been coordinating the search and was still out on a daily basis, Mr Glue said.
Mr Hayes, 25, and his girlfriend Joanna Lam, 24 were believed to have swept off the Haast Pass road by a landslide on September 10.
A body believed to be Ms Lam's was recovered on Friday, but there has been no sign of Mr Hayes'.
Ms Lam's body has yet to be formally identified.
Locals have also been helping to search. About 50 volunteers fanned the river banks and beaches on Monday.
In addition to searchers on foot, other people have used jet skis and horses.