A severely decaying body was found floating in the Binbrook Conservation Area earlier this week.
On Wednesday, canoeists at the Lake Niapenco Reservoir spotted human remains in the water and called police.
Around 1 p.m. Thursday, officers in the marine unit recovered human remains in a heavily weeded area of the reservoir, police say.
"Due to the advanced stages of decomposition, a positive identification could not be made," a police press release reads. "A secondary means of identification such as DNA comparison will have to be undertaken."
DNA testing could take several weeks, police say. An autopsy to help find the cause of death is scheduled for Friday.
Det. Sgt. Joe Stewart of the police homicide unit told CBC Hamilton that the remains are male. "It had obviously been in there a considerable amount of time — perhaps months," he said.
"I dont see the cause of death being released until we have an identity and next of kin are notified."