Lake Ontario

Lake Ontario seen from near
Lake Ontario seen from near Wolcott, New York

Lake Ontario, bounded on the north by Ontario and on the south by Ontario's Niagara Peninsula and by New York State, is one of the five Great Lakes of North America.

The name of the lake is an Iroquois word meaning either "beautiful lake" or "sparkling water". The Canadian province of Ontario was later named after the lake.

Lake Ontario is the eastern-most and smallest in surface area (19,009 square kilometers) of the Great Lakes; although, it exceeds Lake Erie in volume (1639 km). It is the 14th largest lake in the world. Its maximum depth is 802 ft (244 m). Its primary inlet is the Niagara River (from Lake Erie) and primary outlet is the Saint Lawrence River. Other rivers such as the Trent River, the Genesee River, the Oswego River, and the Salmon River also flow into it. Other notable geographic features are Hamilton Harbour, the Bay of Quinte, the Toronto Islands, and the Thousand Islands.

The lake was carved out of soft weak Silurian rocks by the Wisconsonian Ice age glacier which expanded the preglacial Ontarian River valley of approximately the same orientation. The material that was pushed southward was piled in central and western New York in the form of drumlins, kames, and moraines, which reorganized entire drainage systems. As the glacier retreated from New York, it still dammed the present St. Lawrence valley, so that the Lake was at a higher level. This state is known as Lake Iroquois. During that time the lake drained through present Syracuse, New York into the Mohawk River. The old shoreline that was created during this lake stage can be easily recognized by the (now dry) beaches and wave cut hills 15 to 40 kilometers south of the present shoreline.

When the glacier finally melted from the St. Lawrence valley, the outlet was below sea level, and the lake became for a short time a bay of the ocean. Gradually the land rebounded from the release of the weight of about 2 kilometers of ice that had been stacked on it. It is still rebounding about 30 centimeters per century in the St. Lawrence area. Since the ice left that area last, that is the area where the most rapid rebound still is occurring. This means that the lake bed is gradually tilting southward, inundating the south shore and turning river valleys into bays. Both north and south shores have shoreline erosion, but the tilting amplifies this effect on the south shore, causing loss to property owners.

Missing image
Lake Ontario and beach seen from Toronto, Ontario's Humber Bay, west of downtown

The lake has a natural seiche rhythm of eleven minutes. The seiche effect normally is only about 2 centimeters, but can be greatly amplified by earth movement, winds, and atmospheric pressure changes.

Because of its great depth, the lake rarely freezes in winter. The winters of 1934 and 1976 were the only times the lake had ice cover within historic time.

A portion of the Great Lakes Waterway passes through the lake, which is accessible from upstream by the Welland Canal and from downstream by the Saint Lawrence Seaway. The Trent-Severn Waterway for pleasure boats connects Lake Ontario to Georgian Bay of Lake Huron through Lake Simcoe. The Rideau Waterway, also for pleasure boats, connects Lake Ontario at Kingston to the Ottawa River at Ottawa.

The lake was a border between the Huron and their vassals and the Iroquois Confederacy in pre-European times. The first documented westerner to reach the lake was tienne Brul in 1615. Artifacts which are believed to be of Norse origin have been found in the area, indicating possible earlier visits by Europeans.

Today, a large conurbation called the Golden Horseshoe (including Toronto and Hamilton, Ontario) is to be found on the Canadian side at the eastern end of the lake. The excellent farmland on the northern shore of the lake and in the Niagara Peninsula has led it to be a heavily populated area. Today about a quarter of Canada's population lives near the shores of Lake Ontario.

The American shore of the lake is largely rural, with the exception of Rochester, New York. On the south shore, breezes off the cool lake tend to retard fruit bloom until the spring frost danger is past, and the area has become a major fruit growing area, with apples, cherries, pears, plums and peaches grown in many commercial orchards on both sides of Rochester. The Canadian part of the south shore is also a major fruit growing and winemaking area.

During modern times the lake became heavily polluted from industrial chemicals, untreated sewage, including phosphates in laundry detergents, and agricultural fertilizers and chemicals. By the 1960s and 1970s the lake was dying, with frequent algal blooms during the summer, which killed off large quantities of fish, and left stinking piles of seaweed and dead fish along the shores, at times becoming so thick that waves could not break.

Environmental concerns forced a cleanup of industrial and municipal wastes through better treatment plants. Phosphates were banned from detergents, and farm runoff was regulated more closely. Today Lake Ontario has recovered much of its pristine quality, and it is boasted that walleyes, which are a sort of marker of clean water, now abound in its waters. The lake has also become an important sports fishery, with introduced coho and chinook salmon also thriving.

When the cold winds of winter pass over the warmer water of the lake, they pick up moisture and drop it as lake effect snow. Since the prevailing winter winds are from the northwest, the southern and southeastern shoreline of the lake is referred to as the snowbelt. In some winters the area between Oswego and Pulaski may receive twenty or more feet of snowfall. Lake effect snow sometimes reaches as far as Syracuse.

The lake has been plagued with problems of invasive species, including the lamprey, and zebra mussels. The lamprey is controlled by poisoning in the juvenile stage in the streams where they breed. Another recent problem had been E. coli bacteria.

North American Great Lakes
Lake Superior | Lake Michigan | Lake Huron | Lake Erie | Lake Ontario

External link

de:Ontariosee et:Ontario jrv eo:Lago Ontario fr:Lac Ontario he:ימת אונטריו la:Lacus Ontario ja:オンタリオ湖 pl:Jezioro Ontario pt:Lago Ontrio ru:Онтарио (озеро) sk:Jazero Ontario sv:Ontariosjn


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