Corps proposes $7.8 billion plan to restore Everglades' natural hydrology Efforts to tame the Everglades with a vast system of canals, dams, levees, and pumps have taken their toll by damaging South Florida's natural hydrology. In response, the U.S. Army Corps of Engineers (ACE) unveiled a plan in October to reverse much of this damage and restore the region's natural water flow. The key focus of the proposed $7.8 billion Central and Southern Florida Project Comprehensive Review Study, commonly referred to as the "Restudy," is "getting the water right—the right amount of water in the right place at the right time with the right quality," said Terry Rice, a former Corps colonel who headed the agency's Everglades restoration effort for three years. "You've got a system here that's on a pacemaker and you've got to do extraordinary things to get the water right again." With half of the Everglades already lost to urban development and agriculture, the Restudy targets the remaining two million acres, which have suffered greatiy from nutrient-laden runoff and water rerouting. Originally, one large slough ran all the way from Lake Okeechobee down to Everglades National Park and into Florida Bay. To protect the area from frequent flooding and supply water to agriculture, industry, and municipalities, however, 1400 miles of canals were dredged through wedands, artificially connecting estuaries on Florida's east and west coasts with Lake Okeechobee. "We've turned around the way die natural system used to work by 180 degrees," said Thomas Fontaine, director of South Florida Water Management District's (SFWMD's) Everglades System Research Division. "We used to have our deepest water in the Everglades during the summer rainy season, but now we try to keep the water lower during the rainy season for flood control and higher during die winter to supply urban water needs. To get balance back we'll need to change the timing and frequency of water deliveries "
Phosphorus-laced runoff from the Everglades Agricultural Area has led to an explosion of such nuisance species as cattails, which outcompete sawgrass under conditions of elevated nutrients and increased flooding.
When water levels in the lake rise too high, water is released to the estuaries through a series of gates and canals. During the dry season, the estuaries become starved for freshwater. These unnatural discharges have led to a loss of vital seagrass beds and oyster bars, degraded water quality, and fish kills, according to SFWMD studies. Compounding the problem are excessive nutrients entering Lake Okeechobee from the Everglades Agricultural Area (EAA), which have fueled large algal blooms, changes in the composition of bottom-dwelling animals, and high inputs of phosphorus from the lake's sediments to the water column, according to SFWMD. Nutrient-laced water from Lake Okeechobee also flows into the Everglades National Park where native vegetation such as s r\ W P T 3 ^ S
and spike rush has given cattails which thrive in locations with high phosphorus concentrations Fontaine said In addition he noted t h a t altered water flow patterns land to development have led to a °t(W deHine in wading bird nnlatin
The Restudy seeks to regain system balance by removing more than 500 miles of manmade impediments to reestablish natural water flow and developing some 30,000 acres of constructed wetlands to treat urban and agricul-
tural runoff before it is discharged to natural areas throughout the system. These wetlands supplement the roughly 47,000 acres of constructed wedands already under development to trap phosphorus runoff from die EAA. To address the competing needs of adequate water supplies and flood control, ACE plans to maintain surface water storage reservoirs and water preserve areas, utilize underground aquifer storage, and reuse wastewater. "Right now, we're losing 1.7 million acre feet of water a year to the ocean that used to be maintained in the system, and this plan will keep over 90% of that water in the system to be used for things it used to do," Rice said. Developing more water storage areas will provide continued flood control and water supply assurances, while offering more buffer zones between natural areas and urban and agricultural areas. But these additional water storage areas also are fueling controversy. Aquifer storage and recovery is appealing because no water is lost through evaporation. But the technology has not yet been implemented at the scale being proposed by the Restudy, so it is risky, as well as expensive, as is water reuse. Barbara Miedema, a public relations manager with the Sugar Cane Growers Cooperative said "What this plan seems to do is take regional water supplies away from existing and provide that water to the vironment while transferring istine users to alternative technologies If thev don't work and users can't set water from the regional systpm where does that leave the population?" The Restudy's premise rests on the results of several scientific models, which compare the entire present-day watershed, including all the canals, levees, pump structures, gated culverts, and urban and agricultural areas, with the water depth, flow rate, and flow direction that used to occur under the natural system. After the public has had a chance to review the Restudy and issue comments, a final report will be sent to Congress by July 1999. —KRIS CHRISTEN
DEC. 1, 1998/ENVIRONMENTAL SCIENCE S TECHNOLOGY / NEWS " 5 3 3 A
