Chapter 4A: STA Performance and Compliance

Working in conjunction with the best management practices of the Everglades Agricultural Area (EAA) discussed in the previous chapter, the Stormwater Treatment Areas (STAs) represent the second stage of a phosphorus (P) control program for the northern Everglades. Four of the six STAs are fully operational and are removing P that otherwise would have gone into the Everglades Protection Area (EPA). During Water Year 2002 (WY02), STA-1W, STA-2, STA-5 and STA-6, section 1 treated more than 826 cubic hectometers (670,244 ac-ft) of water, and removed more than 83 metric tons of P, for an overall 71-percent removal rate. Flows and P inflows to the STAs increased considerably from the previous water year’s drier conditions. A summary is provided in Table 4A-1. To date, the four operational STAs have reduced P concentrations to less than 35 parts per billion (ppb), well below the long-term design target of 50 ppb. Since the initiation of STA operation in 1994, the STAs have reduced P loads by approximately 198 tons through April 2002.