status was not enough to prevent water control activities beyond park boundaries from bringing severe ecological degradation—in the form of periodic desiccation, flooding, and water pollution—to the Everglades and to much of its surroundings.

So scant did the water flow become at times that salt water seeped into freshwater streams and aquifers in parts of the Everglades. As water tables dropped, rapid land subsidence occurred in places such as the Everglades Agricultural Area just south of Lake Okeechobee. Oxidation ate away fragile peat soil. As the soil dried out and turned to dust, winds eroded it, sometimes down to the porous limestone bedrock. Elsewhere during the dry season, desiccated marshes caught fire and burned.

As hydrologic conditions changed, wildlife in vast numbers perished or departed. The wading bird population of South Florida has plummeted 90 percent since the 1930s (Lancaster, 1990) and is only 5 percent of what it was before drainage efforts began in the nineteenth century (Brumbach, 1990).

Ecological Effects of the Kissimmee River Channelization

The channelization of the Kissimmee River alone drained 34,000 acres of Kissimmee floodplain wetlands, wiping out 5 billion small fish and 6 billion shrimp (Loftin et al., 1990; Toth, 1990). In addition, 13,000 acres of natural Kissimmee wetlands were converted to "impounded wetlands," resulting in a loss of ecological values (Loftin et al., 1990). Another 7,000 acres of wetlands were obliterated along with about 35 miles of the original river channel when COE's new C-38 canal was excavated (Loftin et al., 1990), and the excavated spoil was piled along the canal banks to form levees. Six indigenous species of fish were extirpated from the river in the process (Toth, 1990).

Channelization caused profound alterations in the riverine-flood-plain hydrologic system—changes in the hydroperiod, amounts of flow, rates of flow, flow distribution, and smoothness of the seasonal transition from high to low flows (Loftin et al., 1990). Natural hydroperiods were eliminated in favor of stable water levels. After channelization, stagnant sections of the old river channel remained as oxbows off the excavated canal but retained little habitat value because of low water flow, large in-channel accumulations of submerged organic matter, and consequent low dissolved oxygen levels (Loftin et al., 1990; Toth, 1990).

Water quality degradation in the Everglades, the Kissimmee, and Lake Okeechobee soon followed the flood control projects. Wastewater from sugarcane fields was regularly drained into the Everglades

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