"It has been three weeks to the day that he went missing - it was pretty near to the hour when they found him.
"It's not a good outcome obviously, but it is closure."
Mr Smith said that after police had finished their formal identification process, his brother would be taken back to Rakaunui marae in Kawhia for his tangi.
He said he was grateful to whanau members and strangers who had helped search for his brother.
"The support from complete strangers wanting to help us meant a lot. We would like to say a big 'thank you' to everyone, we really appreciated all the help."
Senior Sergeant Gael Mockford said the body was reported to police by a member of the public yesterday afternoon as being on the edge of the river near the suburb of Riverlea, in southern Hamilton, about 3km from Waikato Hospital.
She said police were in the process of identifying the body.
Security camera images taken at the hospital showed Mr Smith walking away from the entrance on Pembroke St on March 16.
His whanau members from Kawhia, Waikato, Bay of Plenty and Auckland scoured the city in a vain search for him.
Hamilton Land Search and Rescue were involved in the search and the Hamilton police boat searched the banks of the Waikato River.
The Auckland-based police helicopter searched farm land.