How big is Lake Okeechobee?

Lake Okeechobee, often referred to as Florida’s "Inland Sea," is the largest freshwater lake in the state of Florida and the second-largest freshwater lake contained entirely within the contiguous United States, after Lake Michigan. Its sheer size plays a crucial role in Florida’s hydrology, ecosystem, agriculture, and even hurricane resilience.

Surface Area and Volume

Lake Okeechobee covers an impressive surface area of approximately 730 square miles (1,890 square kilometers), making it larger than the entire cities of New York or Los Angeles. In terms of width and breadth, the lake spans about 40 miles east to west and 30 miles north to south. The name "Okeechobee" itself comes from the Hitchiti words oki (water) and chubi (big), literally meaning “big water,” which is a fitting description.

Despite its expansive surface area, Lake Okeechobee is surprisingly shallow. The average depth is just around 9 feet (2.7 meters), with the maximum depth only reaching about 12 to 14 feet (3.7 to 4.3 meters) in most years, depending on rainfall and management practices. The lake holds roughly 1 trillion gallons of water, or about 5.2 million acre-feet, which fluctuates with seasonal variations and water control efforts.

Elevation and Geography

Lake Okeechobee sits at an elevation of approximately 12 to 15 feet above sea level, though this too is managed carefully by the U.S. Army Corps of Engineers via a system of dikes, canals, and floodgates. The lake’s elevation and water level are critical to balancing flood control, agricultural irrigation, water supply, and ecological health across South Florida.

Geographically, Lake Okeechobee lies in the southern portion of the Florida Peninsula. It spans five counties: Glades, Okeechobee, Martin, Palm Beach, and Hendry. Because of its size and the flat terrain of southern Florida, the lake often appears more like an inland sea, with the opposite shoreline invisible from view.

The Herbert Hoover Dike

Due to the lake’s vast size and the catastrophic flooding events of the early 20th century—most notably the 1928 Okeechobee Hurricane, which killed thousands—the U.S. government constructed the Herbert Hoover Dike, an earthen dam over 140 miles long that encircles the lake. This massive structure is one of the largest civil works projects in U.S. history and is critical to protecting nearby communities from flooding.

Ecological and Economic Importance

The lake's size allows it to support a rich and diverse ecosystem. It provides crucial habitat for fish species such as largemouth bass, bluegill, and crappie, and serves as a critical stopover point for migratory birds along the Atlantic Flyway. Additionally, its waters are used extensively for agriculture, especially for sugarcane and vegetable farming in the surrounding Everglades Agricultural Area.

Water from the lake is also managed and released into the Everglades to the south, and into the Caloosahatchee River and St. Lucie River to the west and east, respectively. These discharges are essential for water management but also raise complex environmental issues concerning nutrient pollution and algal blooms.

In summary, Lake Okeechobee's size—730 square miles with a relatively shallow depth—makes it a unique and vital natural feature of Florida. It serves not only as a massive reservoir but also as a crucial component of the state’s environmental and water management systems. Its impact reaches beyond its boundaries, influencing ecosystems, agriculture, and communities across southern Florida.