The five Great Lakes, Superior, Michigan, Huron, Erie and Ontario, and their connecting channels form the largest fresh surface water system on earth. Covering nearly 95,000 square miles, these freshwater seas hold an estimated 6 quadrillion gallons of water, about one-fifth of the world's fresh surface water supply and nine-tenths of the U.S. supply. From the magnificent spectacle of Niagara Falls, to Mackinac Island's Victorian charm. From rolling dunes and grand vistas, to miles of white sand beaches. From emerald green forests, to blazing sunsets that turn the watery horizon to flame, the journey awaits.
The channels that connect the Great Lakes are an important part of the system. The St. Marys River is the northernmost of these, a 60-mile waterway flowing from Lake Superior down to Lake Huron. At the St. Marys rapids, the Soo Locks bypass the rough waters, providing safe transport for ships. The St. Clair and Detroit rivers, and Lake St. Clair between them, form an 89-mile long channel connecting Lake Huron with Lake Erie. The 35-mile Niagara River links Lakes Erie and Ontario; the manmade Welland Canal also links the two lakes, providing a navigation route around the falls. From Lake Ontario, the water from the Great Lakes flows through the St. Lawrence River to the Atlantic Ocean about 1,000 miles away. Anyone traveling from the mouth of the St. Lawrence River to Duluth, Minnesota (Lake Superior) will journey a greater distance than crossing the Atlantic Ocean.
The Welland Canal is located in the Niagara region of Ontario, Canada between Lake Ontario and Lake Erie. The elevation of Lake Erie is 326 feet higher than that of Lake Ontario, which accounts for Niagara Falls on the bypassed Niagara River. The canal is 27 miles long and includes seven lift locks and one guard lock. Photo at right shows the canal and the Niagara River
Detroit River, Lake St. Clair and St. Clair River is the navigational connection between Lake Erie and Lake Huron. Lake St. Clair is fairly shallow but a deep water channel is maintained to accommodate freighters and other deep-draft vessels. There are no locks in this system. This waterway is a popular fishing and small craft haven, due to the mild currents and facilities for boaters. Their only a few feet of difference in elevations between Lake Huron and Lake Erie, which accounts for the mild current. Photo at left shows the connection between the lakes.
The Saint Marys River connects Lake Huron with Lake Superior. Lake Superior has an elevation 21 feet higher than Lake Huron. The Saint Marys channel is 89 miles long, with the Soo Locks and dam providing the deep water above the former rapids on the river. The Soo Locks (shown at right) are the busiest locks in the world with four chambers that can run at the same time.
The 5-mile long Strait of Mackinac connects Lake Huron and Lake Michigan. There are no locks because the two lakes have the same elevation. Technically these lakes are really two giant lobes of a single lake. In the natural order of things, aside from how they were named, that would make this body of water the largest freshwater lake in the world (in surface area), instead of Lake Superior.
Following are some great cruising guides for those interested in exploring the beautiful Great Lakes. Click on the books for more details.