Lake Superior contains fresh water, is uphill from the ocean by far more than the tides can reach (its mean elevation is 600 feet or so), and is downhill from a number of fresh-water inputs in a well watered part of the US and Canada.
This Great Lake doesn't have tides like the ocean; however, periodically the water levels rise and fall by as much as one foot due to a phenomenon called a seiche (SAYSH, a French word that means to sway back and forth).
Lake Superior is the largest freshwater lake in the world by surface area and the third-largest by volume, holding 10% of the world's surface fresh water.
Do you drink the lake water? Lake Superior is the cleanest of the Great Lakes, and many people drink the water regularly (even in their homes). On trip, the decision is yours. For your safety we bring a high quality water filter or boil our water.
Lake Superior's beaches are open and safe for swimming over 90% of the time, and the water is extremely clear, with an average underwater visibility of 8.3 m (27 ft).
Lawrence Seaway (the Highway H2O): Opened to deep draft navigation in 1959. Distance from the Atlantic Ocean to Duluth, Minnesota via Lake Superior is 2,038 nautical miles and takes 8.5 sailing days.
Utilizing lock infrastructure, vessels are able to overcome changes in waterway elevation. On the Great Lakes Seaway system, 16 locks lift or lower ships a total of 600 feet from Montreal to Lake Superior.
So you know how when you go for a dip in the ocean and you come out covered in salt crust and with the distinct stench of rotting seaweed? Yeah, that doesn't happen in the Great Lakes. The water may be colder, but it's wonderfully clean.
While there have been past “sightings,” most have turned out to be pranks or misidentifications. The reality is that the largest of the Great Lakes (Lake Superior and Michigan) are extremely deep lakes that are too cold for sharks.
Geology of Lake InferiorLake Inferior is an underground lake that is located beneath Lake Superior. It is believed to be formed by a process known as karstification, which is the dissolution of limestone and dolomite rock. This process creates sinkholes, caves, and underground rivers and lakes.
Water flows downhill, and the ocean is at the bottom of the hill, right? But Great Salt Lake sits at the bottom of a closed basin. It's a terminal lake. The only way water can leave is through evaporation.
The primary reason for shipwrecks on the Great Lakes is stormy weather, specifically in the upper portions of Lake Michigan, Lake Huron and Lake Superior. In the late fall and early winter, weather can be particularly treacherous. Most Great Lakes shipwrecks occurred in the late fall.
Lake Superior is the world's largest freshwater lake by area (31,700 mi2 /82,100 km2). It is also the coldest and deepest of the Great Lakes, with a maximum depth of 406 meters (1,332 feet). By most measures, it is the healthiest of all the Great Lakes.
Lake Superior freezes at least in part every year and less frequently in its entirety. The last year that it froze completely was in February 1994. It almost froze completely in March 2003 and this photograph was taken by the GOES satellite on March 7, 2003.