Summit Police are expected to provide an update on the recovery effort in a news conference this afternoon.
First responders searched for the boater, who's been missing since Wednesday afternoon, for about five hours Wednesday with no luck.
Summit Police are leading the search. They said it's being treated as a recovery effort rather than a search and rescue.
First responders arrived at Upper Nashotah Lake shortly before 1:00 p.m. Wednesday after a neighbor called 911 to report someone on the lake yelling for help. They found a capsized sailboat but could not locate the owner.
Police believe the missing person is from the area, but have not identified him or her.
According to the DNR, Upper Nashotah Lake is a private body of water roughly 130 acres in size. At some spots, it can get more than 50 feet deep.