Farmers in the Everglades just barely met the legal requirement for cutting pollution in water over the last year.
According to figures released this week by the South Florida Water Management District, growers dominated by the sugar industry in the 470,000-acre Everglades Agricultural Area cut phosphorus flowing from fields by 27 percent during a year of record rain. That’s two percent above the legal requirement, but far off the 56 percent average maintained over the last 20 years.
To clean up the Everglades, water must be nearly free of phosphorus, at just 10 parts per billion. At its worst in the 1980s, water in the area reached about 500 parts per billion. Today, much of that dirty water stays on fields, with water flowing into nearby conservation areas just two to three times the limit.
Reducing phosphorus under such wet conditions “is an astounding accomplishment by the EAA agricultural community,” district board member Melanie Peterson said in a statement. “More important, this achievement is a testament to the long-term effectiveness of the [best management practices] in cleaning water flowing to the Everglades.”
Water managers closely track phosphorus in the Everglades because the nutrient fuels the growth of cattails and other plants, threatening to choke sawgrass marshes. It can also help trigger algae blooms. This past winter, releases from Lake Okeechobee, where phosphorus levels remain well above what’s considered healthy, helped produce slimy green blooms along the Treasure Coast that shut down swimming spots and led Gov. Rick Scott to declare a state of emergency.
Water from south of the lake was briefly backpumped into the lake over the winter, but the practice largely stopped after environmentalists sued in 2007. Nearly all the phosphorus in the lake now enters from the north. But water to the south needs to stay clean to help revive marshes to the south and Florida Bay, where water managers are speeding up efforts to move more water.
Altogether, farmers kept 51 metric tons of phosphorus from leaving fields with improved farming practices that included applying fertilizer more carefully and keeping phosphorus-carrying soil from washing off fields, the district reported.
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