Invasive species are a problem for Lake Ontario, particularly lamprey and zebra mussels.
The Rideau Waterway, also for pleasure boats, connects Lake Ontario at Kingston to the Ottawa River at Ottawa.
Over two million people live in Lake Ontario's American watershed.
Lake Ontario is the smallest and most easterly of the Great Lakes of North America.
Lake Ontario has an elevation of 246 feet (75 m) above sea level.
Lake Ontario (43°30'N, 78°00'W) is the eastern-most and smallest in surface area (7,540 square miles, 19,529 kmІ) of the Great Lakes, although it exceeds Lake Erie in volume (393 cubic miles, 1639 kmі).
A high-speed passenger/vehicle ferry service across Lake Ontario between Toronto and Rochester was launched on June 17, 2004, using the vessel Spirit of Ontario I.
The name of Lake Ontario is derived from ontarн:io, a Huron word meaning "great lake.
The Trent-Severn Waterway for pleasure boats connects Lake Ontario at the Bay of Quinte to Georgian Bay of Lake Huron passing through the inland Lake Simcoe.
A French map produced in 1712 (currently in the Museum of Civilization ), created by military engineer Jean-Baptiste de Couagne, identified Lake Ontario as "Lac Frontenac."
Close to nine million people, or over a quarter of Canada's population, live in the Lake Ontario watershed.
Today, Lake Ontario has recovered much of its pristine quality.
Lake Ontario suffered tremendously from pollution from industrial and agricultural waste.