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 George (Florida) second largest lake in Florida, after Lake Okeechobee. Lake George was the third largest lake behind Lake Apopka, but conversion of the littoral zone on the northern side of Lake Apopka to farm fields in the previous century reduced its surface area. The name of Lake Welaka is taken from "Welaka" (meaning "chain of lakes"), the name for the St. Johns River in the language of the Timucua, who inhabited the region prior to European settlement. The first European to visit the lake was Pedro Menéndez de Avilés, who as the Spanish governor of Florida, explored the St. Johns River