Okeechobee Waterway of Orlando and extending southward through the Kissimmee River Basin to the Everglades National Park to Florida Bay. The U.S. Army Corps of Engineers manages five locks and dams along the Okeechobee Waterway. The St. Lucie lock was built in 1941 for navigation and flood-control purposes. In 1944, the connecting spillway structure was built for flood and regulatory flow control through the St. Lucie Canal to manage the water level in Lake Okeechobee. The Port Mayaca Lock and Dam was built in 1977 for navigation purposes, to permit the raising of water levels in Lake Okeechobee, and to moderate the
Lake Okeechobee Lake Okeechobee Lake Okeechobee (), also known as Florida's Inland Sea, is the largest freshwater lake in the state of Florida. It is the ninth largest natural freshwater lake in the United States and the second largest natural freshwater lake (the largest being Lake Michigan) contained entirely within the contiguous United States. Okeechobee covers , approximately half the size of the state of Rhode Island, and is exceptionally shallow for a lake of its size, with an average depth of only . The lake is divided between Glades, Okeechobee, Martin, Palm Beach, and Hendry counties. All five counties meet at