Marco Island Waterbody Oxygen Dropping

Prior to 2013, the Florida Department of Environmental Protection (FDEP) standard for healthy oxygen in waterways was a minimum of 5 mg/L as measured by Dissolved Oxygen (DO).

Dissolved Oxygen (DO), which is the amount of free oxygen dissolved in water, is an essential component of the aquatic environment. The most important and commonly used measurement of water quality, it indicates a waterbody’s state of health - that is, the ability to support aquatic life. A vast array of aquatic organisms depends on the presence of adequate levels of oxygen for survival. Generally, waters with DO concentrations of 5.0 mg/L or higher can support a well-balanced, healthy biological community.

In ocean and freshwater environments, the term "hypoxia" refers to low or depleted oxygen in a water body. Hypoxia is often associated with the overgrowth of certain species of algae, which can lead to oxygen depletion when they die, sink to the bottom, and decompose. Some aquatic species cannot tolerate even slight oxygen depletion, and when oxygen falls below natural levels, the result is often complete alteration of the community structure.

Marco Island had healthy levels of oxygen in the waterways until 2019. Since then, oxygen has been dropping. If this trend continues, in one year the entire waterbody would be considered hypoxic.

Florida residents must add an amendment to the Florida constitution for a Right to Clean and Healthy Water (RTCW). Sign the petition: https://www.floridarighttocleanwater.org.