The Great Lakes refers to a conglomerate of freshwater lakes along the northeastern region of North America, straddling a vast area within the US-Canadian border. The Great Lakes consist of Lake Erie, Lake Michigan, Lake Huron, Lake Superior and Lake Ontario. It is known as the largest network of freshwater lakes and covers an estimated surface area of 94,250 square miles. It is sometimes referred to as the “Third Coast” and North Coast in the United States. The Great Lakes account for nearly a fourth of the total volume of freshwater on the surface of the earth.
Great Lakes Boundaries
The Great Lakes are bounded by the US states of New York, Pennsylvania, Indiana, Ohio, Illinois, Minnesota, Wisconsin and Michigan, and Ontario on the Canadian side. Four of the 5 major lakes that make up the Great Lakes occupy both sides of the US-Canadian border and only Lake Michigan is exclusively located within the territorial boundaries of the United States. The Saint Lawrence River is the primary outlet of the Great Lakes, which also distinguishes the boundary separating the 2 countries along a section of the course. It traverses the province of Quebec and cuts through the Gaspé Peninsula on the northern region of the Atlantic.
Great Lakes Topography
The 5 lakes that comprise the Great Lakes occupy separate and distinct basins. They are naturally interconnected and form a single body of freshwater. The Great Lakes form a chain of freshwater lakes that directly link with the east-central portion of North America flowing and extending all the way to the Atlantic. The waters of the Great Lakes emanate from the interior regions of North America along the St. Lawrence River and meander from Lake Superior and down through Lake Michigan and Lake Huron. It flows southward towards Lake Erie and meanders due north towards Lake Ontario.
The waters of Great Lakes are drained by a vast watershed through several tributaries and it is dominated by over 35,000 islands and islets. Aside from the five major lakes – Erie, Huron, Superior, Michigan and Ontario – this large body of freshwater also contains thousand of small lakes, which are classified as inland lakes. Among the 5 major lakes, Lake Michigan is the only body of freshwater that occupies an area located entirely within the territorial boundaries of the United States. The 4 other lakes cover regions on both sides of the US-Canadian border.
Great Lakes Water Levels
The surface levels of Lake Erie, Lake Michigan, Lake Huron and Lake Superior are generally above the water level of the Atlantic Ocean while the surface level of Lake Ontario is below sea level. The upper lakes, which are collectively referred to as the “upper great lakes,” are distinctly separated from Lake Michigan by the variance in the water levels and this highlights the physical impossibility of natural navigation as it is prevented by the Niagara Falls. However, this reference is not universal. For instance, people who are residing along the shores of Lake Superior sometimes refer to the other lakes that comprise this vast body of freshwater as “lower lakes” for the main reason that these lakes have water levels that are lower than Lake Superior.
Transport vessels and bulk freighters normally transfer their cargoes from the northern region of Lake Michigan and Lake Huron and Lake Superior through the ports of Lake Ontario and Lake Erie. This explains why Lake Ontario and Lake Erie are sometime referred to as the lakes “down south” while the 3 other major lakes as “up north.” Sea vessels that are sailing along Lake Michigan are described as “upbound” even if they are going along the natural flow of this body of freshwater.
Links of Great Lakes to the Atlantic
The Great Lakes Waterway and Saint Lawrence Seaway are important ocean trading links of Great Lakes. They paved an important route for ocean-going vessels and bulk freighters sailing along this part of North America. The shift to larger container ships for international trading has limited the traffic of ocean-going vessels along this important trading route mainly because these huge container ships could not fit through the locks of these major waterways. A greater portion of the trading and freight activities within the region involves bulk freighters and bulk materials. Suffice to say, these transport vessels and bulk freighters must have sizes that are equal or less than the maximum size of the Seaway so that they can travel the entire stretch of this trading route all the way to the Atlantic Ocean. Large vessels are limited within the Great Lakes and cargoes rely on barges to gain access to the Illinois Waterway and the Gulf of Mexico.
Notwithstanding the vast area of this body of freshwater, a larger section of the Great Lakes are frozen during the winter months. Thus, there are occasional interruptions in the shipping activities during this time of the year. Several icebreakers ply the route during the winter months to ensure that the shipping lanes along the Great Lakes remain open during most parts of winter.
