Editing Everglades (section)

===Water quality===
[[File:Mercury warning sign in Everglades National Park.JPG|thumb|upright|Warnings are placed in Everglades National Park to dissuade people from eating fish due to high mercury content. This warning explicitly mentions [[Bass (fish)|bass]].]]

Further problems with the environment arose when a vast [[algal bloom]] appeared in one-fifth of Lake Okeechobee in 1986, the same year [[Typha|cattails]] were discovered overtaking sawgrass marshes in [[Loxahatchee National Wildlife Refuge]]. Scientists discovered that [[phosphorus]], used as a fertilizer in the EAA, was flushed into canals and pumped back into the lake.<ref>Lodge, p.&nbsp;230.</ref> When the lake drained, the phosphorus entered the water in the marshes, changing the nutrient levels. It kept periphyton from forming marl, one of two soils in the Everglades. The arrival of phosphorus allowed cattails to spread quickly. The cattails grew in dense mats—too thick for birds or alligators to nest in. It also dissolved oxygen in the peat, promoted algae, and prohibited the growth of native invertebrates on the bottom of the food chain.<ref>Davis, Steven. "Phosphorus Inputs and Vegetation Sensitivity in the Everglades" in ''Everglades: The Ecosystem and its Restoration'', Steven Davis and John Ogden, eds. (1994), St. Lucie Press. {{ISBN|0-9634030-2-8}}</ref>

At the same time [[Mercury (element)|mercury]] was found in local fish at such high levels that consumption warnings were posted for fishermen. A [[Florida panther]] was found dead with levels of mercury high enough to kill a human.<ref name="lodgemercury">Lodge, pp.&nbsp;231–233.</ref> Scientists found that power plants and incinerators using fossil fuels were expelling mercury into the atmosphere, and it fell as rain or dust during droughts. The naturally occurring bacteria that reduce sulfur in the Everglades ecosystem were transforming the mercury into [[methylmercury]], and it was [[Bioaccumulation|bioaccumulating]] through the food chain.<ref name="lodgemercury" /> Stricter emissions standards helped lower mercury coming from power plants and incinerators, which in turn lowered mercury levels found in animals, though they continue to be a concern.<ref name="lodgemercury" />

The [[Everglades Forever Act]], introduced by Governor [[Lawton Chiles]] in 1994, was an attempt to legislate the lowering of phosphorus in Everglades waterways. The act put the [[South Florida Water Management District]] (SFWMD) and the [[Florida Department of Environmental Protection]] (DEP) in charge of testing and enforcing low phosphorus levels: 10&nbsp;parts per billion (ppb) (down from 500&nbsp;ppb in the 1980s).<ref name="efa">{{cite web|title = Florida Statutes (Supplement 1994) [Everglades Forever Act]|work = Chapter 373: Water Resources, Part IV. Management and Storage of Surface Waters, 373.4592 Everglades improvement and management|publisher = [[University of Miami]] School of Law|year = 1997|url = http://exchange.law.miami.edu/everglades/statutes/state/florida/E_forever.htm|access-date = 2008-05-21|url-status = dead|archive-url = https://web.archive.org/web/20081028150828/http://exchange.law.miami.edu/everglades/statutes/state/florida/E_forever.htm|archive-date = 2008-10-28
}}</ref> The SFWMD built Stormwater Treatment Areas (STAs) near sugarcane fields where water leaving the EAA flows into ponds lined with lime rock and layers of peat and [[calcareous]] periphyton. Testing has shown this method to be more effective than previously anticipated, bringing levels from 80&nbsp;ppb to 10&nbsp;ppb.<ref>{{cite web|title = Periphyton-based Stormwater Treatment Area (PSTA) Technology|publisher = The Journey to Restore America's Everglades|date = December 2003|url = http://www.evergladesplan.org/docs/fs_psta_hires.pdf|access-date = 2008-05-22|url-status = dead|archive-url = https://web.archive.org/web/20080529070046/http://www.evergladesplan.org/docs/fs_psta_hires.pdf|archive-date = 2008-05-29
}}</ref>