Okeechobee Mudfest, Florida, United States

The floor of the lake is a limestone basin, and the lake varies in depth from 1 to 13 feet (0.3 to 4 m). Its water is somewhat murky from nutrient-enriched runoff from surrounding farmlands. The surface is above sea level. The lake is enclosed by the up to 30-foot (9 m) high Herbert Hoover Dike built by the U.S. Army Corps of Engineers after a hurricane in 1928 breached the old dike, flooding surrounding communities and claiming thousands of lives. Water flows into Lake Okeechobee from several sources, including the Kissimmee River, Fisheating Creek, Lake Istokpoga, Taylor Creek, and smaller sources such as Nubbin Slough and Nicodemus Slough. The Kissimmee River is the largest source, providing more than 60% of the water flowing into Lake Okeechobee. Fisheating Creek is the second largest source for the lake, with about 9% of the total inflow. Prior to the 20th century, Lake Istokpoga was connected to the Kissimee River by Istokpoga Creek, but during the rainy season Lake Istokpoga overflowed, with the water flowing in a 25-mile wide sheet across the Indian Prairie into Lake Okeechobee. Today Lake Istokpoga drains into Lake Okeechobee through several canals that drain the Indian Prairie, and into the Kissimmee River through a canal that has replaced Istokpoga Creek. Historically, outflow from the lake was by sheet flow over the Everglades, but most of the outflow has been diverted to dredged canals connecting to coastal rivers, such as the Miami River, the New River on the east, and the Caloosahatchee River (via the Caloosahatchee Canal and Lake Hicpochee) on the southwest.
Hurricanes
In 1926 the Great Miami Hurricane hit the Lake Okeechobee area, killing approximately 300 people. Two years later in 1928, the Okeechobee Hurricane crossed over the lake, killing thousands. The Red Cross reported a figure of 1,836 deaths which the National Weather Service initially accepted, but in 2003, the number was revised to "at least 2,500". In both cases the catastrophe was caused by flooding from a storm surge when strong winds drove water over the 6-foot (2 m) mud dike that circled the lake at the time.