We have been laboring under the perception for some time now that the Marco Island waterways are seriously “polluted.” Really? This may not be true, according to public reports available to Marco Island residents.
The Florida Department of Environmental Protection (FDEP) has identified excessive levels of total nitrogen (TN) and total phosphorus (TP) in the surface waters as among the most severe water quality problems facing the state. It has given special consideration to preventing further degradation of waters which are very high in nutrient concentrations and protecting waters that are very sensitive to nutrient enrichment, including those that contain very low nutrient concentrations (<0.3 mg/L TN or <0.4 mg/L TP).
A Turrell Hall & Associates report (2019) states that the only water quality impairment for Marco Island is for Total Nitrogen (TN), which had an average reading of 0.634 mg/L (2018), which constitutes “impaired waters.”
Good news! The latest water quality measurements for TN within the Marco Waterways dropped to an average of 0.38 mg/L for the last 3 months of 2020. The Marco waterways measurement of TN is almost down to the “very low levels” as defined by FDEP!
The current Marco Island waterways TN measurements compare favorably with other locations in South Florida. According to the South Florida Water Management District (SFWMD) 2020 South Florida Environmental Report (SFER), Water Year 2019, the 177 water quality monitoring stations in the Everglades Protection Area (EPA) had an average TN measurement of 1.37 mg/L, 3.6 times higher than the recent readings on Marco Island. The Everglades Protection Area is an area of the Everglades that includes the Loxahatchee National Wildlife Refuge (LNWR) and the Everglades National Park (ENP).
If this positive trend for the TN measurement continues, it would show the significant progress made by the Marco Island Waterways Committee, the Marco Island Water and Sewer Department, and the residents of Marco Island.
Some of the many actions taken to reduce the nitrogen levels in the past few years include: Residential conversions to Florida Friendly Landscaping, The Water & Sewer plant reduced TN in the reuse water by 50%, Fertilizer ordinance passed, Suntree filters remain in place along Collier Boulevard, Swale conversions that improve percolation.
Maybe the Marco Island waterways are not so impaired after all? We all wait with “crossed fingers” to see if this positive trend continues into 2021.
Marco Island, Florida