Hydrology of the pre-drainage system of the Everglades in southern Florida

Parker, Garald

This article contains historical information on the flow regime in the Everglades. Maps included. The Everglades, covering an area of about 3,900 square miles, is the lower segment of a huge, naturally integrated drainage system of about 9,000 square miles. Lake Okeechobee occupies a 730 square-mile basin with its floor at sea level almost in the middle of this huge system. In pre-drainage days, as now, drainage began in the northern-most part of the Kissimmee River basin, near Orlando, and flowed southeast into the lake. During these pre-drainage times most of the KLOE (Kissimmee-Lake Okeechobee-Everglades) drainage system was inundated much of the time and during flood periods when the lake's level rose to heights of about 14.6 feet msl (mean sea level), two separate segments of the lake's southern shore totalling about 19 miles overflowed into the Everglades. When lake levels reached about 18 feet msl, the entire southern shore for a length of about 32 miles poured a sheet flood into the upper glades. Sheet flow continued from there on south to the Bay of Florida with notable discharge to the Atlantic Ocean through such streams as New and Miami Rivers, and through the transverse glades across the coastal ridge. During extended droughts, the sawgrass plains dried out and at times fierce fires swept the glades burning the muck and peat down to the lowered water table. Buried ash layers incorporated into the body of the peat deposits give mute testimony to these prehistoric fires and the severe droughts that allowed them to burn the dried-out peat.