Billy Bishop Toronto City Water Aerodrome (TC LID: CPZ9) is located in Toronto Harbour, Toronto, Ontario, Canada, adjacent to Billy Bishop Toronto City Airport on the Toronto Islands. Closed briefly in 2005, the aerodrome provides the only facility for floatplanes in the city. The aerodrome is classified as an airport of entry by Nav Canada and is staffed by the Canada Border Services Agency (CBSA). CBSA officers at this airport can handle general aviation aircraft only, with no more than 15 passengers.

The aerodrome was established in 1930 and consists of a seaplane ramp and docks on the Toronto Inner Harbour side of the Toronto Islands.

Seaplanes or floatplanes land at the northeast end of the airport between Trans-Capital Air and the East Run-Up Bay. A ramp, approximately 150 ft (46 m), leads up towards the terminal. Trans-Capital Air provides docking and beaching assistance.

Cameron Air Services is the major seaplane operator at the aerodrome providing corporate air charters and tours.

The aerodrome is open from May to November when the harbour is not frozen over.

Control over the airspace and waterway is under the authority of Billy Bishop Toronto City Airport. No scheduled flights are allowed at the aerodrome.

• List of airports in the Greater Toronto Area

• Floatplane operational procedures