Sunshine Coast RCMP Cpl. Steven Chubey said both of the plane's pontoons were damaged by the propeller, but held up for a successful emergency landing around 1:40 p.m. PT.
Canadian Marine Search and Rescue found the plane, a Seair Beaver DHC-2, afloat in the bay and with the help of two other boats, towed it to shore.
The pilot and the three passengers were not injured, Chubey said.
"Losing a propeller is certainly an uncommon occurrence," Chubey said in a written statement. "Luckily, the pontoons have several compartments, which contributed to the sea plane staying afloat."
He said the Transportation Safety Board of Canada will be investigating why the propeller malfunctioned.