How Many Miles Wide Is Lake Superior

Size of Lake Superior

Lake Superior is the largest of the North American Great Lakes, covering an area of 31,700 square miles. This makes it the largest freshwater lake in the world by surface area. It has a maximum depth of 483 feet, making it the largest and deepest of the Great Lakes. In comparison, its surface area is almost three times the size of the state of New Jersey and is the equivalent of the state of South Carolina. It has a shoreline of 2,726 miles or 4,385 kilometers, which makes Lake Superior the largest and longest natural body of fresh water in the world.

The vastness of Lake Superior is astonishing and its dimensions have been studied by many. Its maximum length is approximately 350 miles, running from Duluth, Minnesota, in the west to the St. Marys River in the east. Measured east to west, the breadth of the lake is roughly 160 miles, while its north-south length is approximately 210 miles. Much like its vastness, the lake’s water volume is equally impressive. The lake holds an approximate total of 2,900 cubic miles of water, which is enough to cover the entire United States of America in more than a foot of water!

At its widest point, Lake Superior is approximately 160 miles across. It is approximately 80 miles at its widest point between Duluth, Minnesota and Thunder Bay, Ontario. The lake’s width varies in other locations, depending on its depth at the time of measurement. For example, at its shallowest point, the lake is only 70 feet deep. However, it can reach a maximum depth of over 500 feet in certain areas.

Since it is the largest of all the Great Lakes, Lake Superior is often used by locals as well as travelers for a variety of activities, including fishing, boating, sailing, and sightseeing. The lake is also a popular destination for scientific research and environmental protection efforts, as the lake houses many rare species of fish and plant life. In addition, the surrounding Lake Superior National Park offers scenic hiking trails, camping grounds, sandy beaches, and a number of picturesque lighthouses.


Lake Superior is part of a temperate climate zone where summer temperatures can reach into the high 80s and winter temperatures can drop to below zero. The lake is bordered by Michigan, Wisconsin, and Minnesota in the United States along with Ontario in Canada. Its immense size affects and moderates the climate in the region. Although much of the lake’s annual precipitation comes from snowfall that falls mostly on the Canadian shore, the lake’s heat can create a fog and mist in the wintertime and humidity during the summer and fall.

Located partly in a temperate zone and partly in a subarctic zone, the lake’s surface temperature usually ranges from 39 to 75 degrees Fahrenheit in the summer, and from 33 to 74 degrees Fahrenheit in the winter. During the hottest days of the summer months, the lake water temperature can reach 77 degrees Fahrenheit. Due to the mountains and hills around the lake, some areas remain cooler in the summer and warmer in winter than other areas.

Lake Superior is also responsible for the moderated temperature of Minnesota, Wisconsin, Ontario, and Michigan. It stores heat during the summer months and releases heat at night, creating a cooler climate in the region. This helps prevent inhabitants of the region from experiencing extreme fluctuations in temperature.

Flora and Fauna

Lake Superior is home to a variety of wildlife species. There are over 80 species of fish that live in the lake, including trout, salmon, whitefish, bass, walleye, and muskie. Due to its immense size, the lake is home to over 70 types of birds, including swans, singing sandpipers, and geese. Mammals that make the lake their home include beavers, otters, and even black bears.

In addition to fauna, the lake is also a refuge for several plant species. These include reeds, wild rice, sedges, and algae. Zigzag Bladderwort and Watermeal are two of the lake’s most abundant plant species. The region’s vegetation is important for allowing waterfowl to feed and nest. The lake’s zooplankton and phytoplankton also provide a food source for many of the fish that inhabit the lake.

Furthermore, Lake Superior is home to hundreds of islands, each of them unique in their own way. Some of them are just large rock formations with sparse vegetation, while others have small communities on them. With its abundant wildlife, stunning views and clear waters, it is no wonder why Lake Superior is an important part of the Great Lakes eco-system and a popular destination for those looking to witness its beauty.


Formed over 10,000 years ago, at the end of the most recent Ice Age, Lake Superior is the remnant of the ancient glacial river basin. Its form is similar to an inverted triangle, thus making it the largest of all the Great Lakes in terms of surface area. Its deepest point is located in a small bay near Isle Royale in Marena, Michigan.

The lake’s bottom is composed of bedrock, gravel, sand, and clay. These deposits primarily consist of sedimentary rocks from the Proterozoic era, which is estimated to span between two to four billion years ago. In the west, the lake’s bottom is composed of granite, which is believed to be over two billion years old. In addition, the lake’s shoreline is mostly composed of sandstone and limestone, which are estimated to have formed 500 million years ago.

The lake also contains hundreds of rivers, streams and creeks, although they constitute only a small portion of the lake’s total surface area. Due to its immense size, Lake Superior is one of the most studied freshwater systems in the world. Its geology and hydrology are regularly evaluated and studied by scientists.

Economic Impact

Lake Superior has had an immense impact on the local economies of the surrounding states, provinces and countries. Due to its position as the largest inland body of freshwater, the lake is essential for the fishing and recreational industries. It is also the largest source of freshwater on the continent, which makes it a major contributor to the agricultural industry in the region.

On the other hand, the lake’s energy production has been highly sought after by businesses and industries due to its huge supply of electricity. The lake generates enough electricity to power much of the nearby regions, although much of the energy generated goes to the United States, due to the higher demand for electricity there. Additionally, the lake’s abundance of minerals and rocks makes it a much-sought after destination for miners and quarry owners.

Moreover, the lake is widely used for transportation purposes. The lake has several ports that are frequently used for shipping and boat transportation. In addition, there are many ferries that carry tourists and local travelers alike across the lake. Finally, the lake is also well known for its tourism industry. According to several studies, over 10 million people from around the world visit the lake every year.


Due to its immense size, Lake Superior contains a vast amount of pollutants. Although the lake’s water is mostly clean, there are many sources of pollutants that can contaminate it, such as urban and industrial runoff, agricultural fertilizers, and other chemicals. In recent years, nitrogen and phosphorus have been found in the lake in high concentrations, leading to an increase in the growth of algae and aquatic weeds.

The pollutants can have a detrimental effect on the wildlife living in the lake. These pollutants can lead to an increase in the number of invasive species and a decrease in the health of native species. In addition, the pollutants can cause algal blooms, which in turn can create hypoxic zones, or areas of low oxygen in the water. These hypoxic zones can be extremely harmful to the fish, animals, and plants that live in the lake.

To combat this situation, governments in Canada and the United States are taking measures to reduce the amount of pollution entering the lake. These efforts involve restrictions on phosphorous and nitrogen runoff from farms, streamline treatment of wastewater from urban sources, and even recognizing certain areas of the lake as Significant Areas of Conservation.

Preservation Efforts

Some of the attempts to preserve the lake include programs to reduce the introduction of foreign species. Non-native species such as bluefish flounder, and Atlantic salmon have been introduced to the lake in recent years and have posed a danger to the native species. Predation and competition for resources have led to a decline in the population of native species, such as lake trout and walleye.

To address this issue, organizations have been working to restore native species of fish. This includes introducing hatchery-raised fish into the lake and creating a lake wide effort to monitor its populations. In addition, certain species of amphibians and reptiles have been identified as endangered and are being helped by the Lake Superior National Parks species restoration efforts.

The lake has also been designated as an Important Bird Area by the National Audubon Society, and many organizations have started projects to conserve its bird population. These include protecting and restoring critical nesting sites and wetland habitats, as well as creating sanctuaries for migrating waterfowl.

In addition, many environmental organizations have initiated public awareness campaigns to educate people about the importance of Lake Superior’s preservation. Programs such as “Lake Superior Forever” aim to engage the public in various activities and promote sustainable practices. This includes reducing the consumption of single-use plastics, avoiding the release of foreign chemicals, and encouraging recycling.


Lake Superior and the surrounding region are home to a wealth of wildlife and spectacular scenery. Its immense size and natural beauty continue to captivate scientists, travelers, and locals alike. Although pollution and invasive species have posed a threat to the lake, numerous organizations have been working to sustain and restore its beauty through preservation and public awareness efforts.

Todd Hashimoto is a nature writer and enthusiast. He has a special interest in ecotourism, particularly for lakes around the world. He has traveled extensively for his research, visiting some of the most renowned bodies of water on every continent. His writing covers topics like lake ecology and conservation as well as interesting historical and cultural facts about famous lakes. He is passionate about bringing attention to the beauty and importance of these natural wonders in hopes of promoting their protection.

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