Monday, October 11, 2010

The Use of Best Management Practices to Reduce Nutrient Pollution in the Everglades Agricultural Area

It is only after my recent move to South Florida where I routinely drive on the Sawgrass Expressway that I appreciate how the wild beauty of the South Florida Everglades lives cheek to jowl with the buzz and press of busy city life.

William H. Owen captures this juxtaposition in a recent Earth Magazine article:
As the sun rises over the vast Florida Everglades, the endangered Florida panther quietly stalks a white-tailed deer in the tall grass. A raccoon fishes for its breakfast of crayfish. A small flock of rose-colored waterfowl flies overhead, a reminder of the vast flocks of wading birds that once called the Everglades home. A couple of otters roll around in the water nearby, keeping a watchful eye out for ubiquitous alligators. Manatees swim silently below the surface in Florida Bay, at the southern end of the Everglades ecosystem. Suddenly, a tractor engine revs to life as a farmer prepares to harvest his sugarcane, and the noise of commuters driving to work on the Sawgrass Expressway disturbs the calm. Such is life in the Everglades, where modern civilization meets wild in a vast subtropical wetland.

The Everglades is the largest subtropical wetland in the United States. It is an internationally recognized ecosystem that covers approximately two million acres in South Florida. Urban and agricultural development has endangered the biotic integrity of this ecosystem. One example of this development is the Everglades Agricultural Area (EAA). The EAA is one of several large portions of the original Everglades that was drained for commercial, agricultural and residential development. The EAA is approximately 700,000 acres and is 27% of the original Everglades. Drainage waters from the agricultural lands in the EAA contain nutrients, primarily phosphorous, from the use of fertilizers, herbicides and pesticides. This agricultural runoff flows downstream to areas that include the Everglades National Park. These excess nutrients have allowed nutrient loving plants like cattails to overrun the wetlands, displacing native species such as sawgrass.

In an article titled Reducing Nutrient Pollution in the Everglades Agricultural Area through Best Management Practices, Professor Alfred R. Light chronicles the social, legal and regulatory history of nutrient pollution reduction efforts in the EAA. Professor Light explains how the EAA farmers have recently used Best Management Practices to take the irrigation water with high phosphorous levels that flows into their fields and reduce those levels before allowing the runoff to drain downstream. Professor Light suggests that the successful use of Best Management Practices by EAA farmers will be a bellwether for other US farmers facing similar nutrient pollution problems. The abstract of the Article reads:
Some Florida farmers recently have been reducing the level of nutrient pollution discharged from their fields and entering sensitive Florida ecosystems from the level found in the irrigation water they use. They are doing this while continuing to operate their productive farms. Setting a water quality standard seems to have driven actual “real world” improvements in water quality in Florida, including development of the data and research needed to support those improvements. Mandatory BMPs seem to have worked in reducing phosphorus concentrations in water leaving the EAA. In fact, phosphorus concentrations in water leaving the EAA are about half of the concentrations in irrigation water entering the region. Other regions of the country with significant nutrient pollution thus may be looking to Florida to find out how farmers can be part of the solution rather than part of the problem. Florida’s BMP program in the EAA thus may be a bellwether for other states seeking to confront the challenges of nutrient pollution.



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