Everything to Know about Lake Ontario

Canada’s easternmost and tiniest Great Lake is Lake Ontario. The lake’s maximum breadth is 53 miles. Its longest axis runs approximately east to west for a total of 193 miles. Besides the lake’s surface size of 7,340 square miles, the drainage basin of the lake encompasses a total area of 24,720 square miles.

While the Niagara River is the lake’s primary source of water, it also receives water from the Trent River, Oswego, the Genesee, and Black rivers. Five islands span the lake’s easternmost 30 miles before it empties into the St. Lawrence River at Kingston, Ontario.

The south shore has the strongest flow of the eastward-moving surface current. With Lake Erie to the southwest, the region is linked by the navigable Welland Canal and the naturally occurring Niagara River. The Rideau Canal travels to the capital city of Ottawa, in the northeast, from Kingston in the southeast.

Geology of the Lake

Ontario geology is the study of the rock formations in Canada’s most populous province. The oldest rocks on Earth can be found in Ontario. It consists of igneous and metamorphic rock from the Precambrian era, covered by sedimentary rock and soil from more recent epochs.

The Canadian Shield occupies roughly 61% of the province. Additionally, the shield can be cut into thirds, each of which represents a distinct region. The Superior province, which encompasses around 70% of the Shield component in Ontario, is located in the far northern areas of the shield, to the north and west of Sudbury. From Sault Ste. Marie to Kirkland Lake, the southern province, is a thin strip of land. The Grenville Province occupies the south-central region, and two basins containing Phanerozoic sediments flank its edges.

History of the Lake

The Iroquoians named the lake “lake of bright waters.” About 7,000 years ago, when they first settled there, the First Nations were the first people to use the watershed. In the present day, 9 million people in Ontario, Canada, and New York State, USA, call Lake Ontario home and rely on it as a water supply.

Lake Ontario is a natural marvel because of its enormous size and its proximity to the Atlantic Ocean. There is no Great Lakes water that does not pass through this lake. In both directions, fish are constantly making the journey from the salty ocean to the freshwater lake. Numerous ecosystems can be found throughout the lake, from dune fields to swamps to forests to precipitous cliffs.

Fish populations in Lake Ontario declined due to overfishing in the 1800s, pollution, and industrialization in the 1900s. Fish like the eel and sturgeon used to migrate in huge numbers between the lake and the ocean before the construction of dams on the St. Lawrence River hindered their movement

At least ten fish species have gone extinct, and 15 new foreign species have been introduced to the world’s oceans in the last 200 years as a direct result of human activity. Not all of Lake Ontario’s natural biodiversity can be restored, but a lot of work is being done to try.

Prince Edward County, Ontario, is home to the world’s largest freshwater dune system, located in Sandbanks Provincial Park. The plants, animals, and migratory birds that call these seashore ecosystems home are all unique and vital.

In the past, the entire Canadian continent was covered by the Laurentide Glacier. In the last 14,000 years, it’s been slowly melting away. Lake Iroquois, an even bigger version of modern-day Lake Ontario, was left behind by the receding glacier. The steep ridge that separates the north and south sides of Davenport Road in Toronto is visible to anybody who has driven across the road. The ancient shoreline of Lake Iroquois was here.

When the Laurentide Glacier in the St. Lawrence River valley melted, water from Lake Iroquois gushed out into the Atlantic. Lake Admiralty, a smaller lake, remained. This bluff or scarp stretches from Toronto’s Scarborough Bluffs to beyond the waters of Hanlans Island. It was once the shore of the submerged Lake Admiralty. Lake Ontario was formed when the underlying rock settled and the Thousand Islands to the east of Kingston were pushed farther inland.

Threats to the Lake

Due to serious environmental degradation, 43 Great Lakes municipalities were labelled “Areas of Concern” in the 1980s. The regions of Lake Ontario include the Bay of Quinte, Hamilton Harbour, Eighteen Mile Creek, Oswego River, Metro Toronto, Rochester Embayment, and Port Hope Harbour. Urbanization, energy generation, and sewage and stormwater pollution are currently the major dangers to Lake Ontario.

Ontario Lake Waterkeeper is committed to restoring and protecting the lake because of its critical importance to human populations. The lake provides drinking water for nine million people. About a quarter of Canada’s population resides in the watershed. There aren’t many bodies of water that are as vital to as many people.


Lake Ontario is home to a wide variety of fish, including walleye, chinook salmon, coho salmon, and several species of trout, such as rainbow and steelhead. Most of the lake bottom in the coastal portions is covered by invasive mussels.

Because of Lake Ontario’s temperate environment, it has developed into a major producer of various fruits, including apples, pears, cherries, peaches, and plums.

Migration routes cross or intersect with Lake Ontario, making it an essential stopover for many species of migrating birds. Many species of waterfowl, including ducks, geese, swans, loons, grebes, and others, make their homes in Lake Ontario. Eagles, hawks, and other birds of prey are frequent there.

Final Word – How Can You Visit the Lake?

Lake Ontario’s massive size makes it feel almost like an ocean. This freshwater lake is one of five in North America and spans an area of 19,000 square kilometers, with New York State to its southeast and Toronto to its west. The waterfront features tree-lined parks, sandy beaches, and waterfront eateries. You can visit the lake by approaching Trip Advisor.

The McClain Family

We hope we helped. Please let us know of any place that you want to know about in NYS or if we did a poor job with any part of this. Our goal is to help as many people as possible.

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