Authorities say a man drowned after he slipped below the surface of a northern Colorado lake.

Routt County Coroner Rob Ryg says 64-year-old David Bass, of Hutchinson, did not have any heart issues and was "a very healthy man" when he drowned at Steamboat Lake on Friday.

Bass was with another man on the shore trying to fix a problem with their boat's trolling motor. The boat drifted away, and Bass swam after it before disappearing.

His body was recovered just after midnight early Saturday morning.