Lake Superior, which forms part of the border between the United States and Canada, is widely recognized as the largest freshwater lake on Earth by surface area. This immense body of water dominates the North American landscape, stretching across two countries and three U.S. states. Understanding the volume of water held within this basin provides a clear picture of its massive scale and significance.
The Volume Quantification
The immense scale of Lake Superior translates into a staggering volume of water, estimated to be approximately 3 quadrillion gallons. This number is often conveyed in scientific units, with the lake holding about 2,900 cubic miles of water. For those who use the metric system, this volume is equivalent to roughly 12,100 cubic kilometers.
The enormous size of this freshwater reservoir makes it the third-largest freshwater lake in the world by volume, surpassed only by Lake Baikal and Lake Tanganyika, demonstrating why the lake is considered one of the planet’s greatest natural resources.
Scale and Global Significance
The volume of Lake Superior represents nearly 10% of the world’s accessible surface fresh water, underscoring the lake’s importance far beyond the North American continent. The water contained within the lake is so vast that it could cover the entire landmass of North and South America in water to a depth of one foot.
The lake holds a massive quantity of water, equivalent to the combined volume of all the other Great Lakes, with enough left over to fill three more Lake Eries. Another way to appreciate the magnitude of this volume is by considering the water’s residence time, which is the amount of time it would take for all the water in the lake to be completely replaced. Due to its size, the average drop of water remains in Lake Superior for an estimated 191 years before it leaves the basin.
Physical Characteristics Defining Volume
The calculated volume is a direct result of the lake’s enormous dimensions, its surface area and its depth. Lake Superior has a surface area of approximately 31,700 square miles, making it larger than many countries. This extensive area acts as the top boundary of the water body used in the volume calculation.
The lake’s depth is the other determinant of its volume, as the two characteristics are multiplied to determine the total capacity. Lake Superior reaches a maximum depth of 1,333 feet, which is the deepest point in the Great Lakes system. The average depth across the entire lake basin is measured at 483 feet, a figure that, when combined with the surface area, mathematically defines the lake’s total volume.