beemats floating wetlands

MERRITT RIDGE STORMWATER TREATMENT AREA

Brevard County, Florida


This salt influenced pond is located on Merritt Island, between the Indian and Banana Rivers, two estuaries in east central Florida.  It is an arrowhead shaped, 6.68 acre stormwater treatment area, with multiple runoff inputs, but only one outfall.  We conducted a one year experiment in 2016 – 2017 to assess the impact of vertical water circulation on nutrient uptake rates by plants growing on floating wetland platforms. 

The floating wetlands in this pond cover 16,727 square feet, which represents 5% of the surface area of the waterbody.  We divided the floating wetlands into two open squares and placed one at each end of the pond.  A Solar Bee 10,000 water circulator was anchored in the middle of the wetland installation on the south end of the pond and the northern installation served as a control.  After twelve months, all of the plants were harvested from both floating wetlands and weighed.  Representative samples were collected, iced and delivered to ENCO Labs in Orlando for nutrient composition analysis.   The wetland islands surrounding the Solar Bee produced 30 % more biomass than the control wetlands.  The plants benefiting from vertical water circulation took up 2.3 times more nitrogen and 3 times more phosphorus than the plants without circulation.

In early 2018, we moved the Solar Bee to another Brevard County stormwater pond at Wickham Park.  The floating wetlands in the Merritt Ridge Pond were reconfigured to form 33 -  512 square foot islands.  During the past six years,  the average annual nutrient harvest rates have been 222.13 grams N / m2 year and 35.17 grams P / m2 / year. That means we have kept 4,565.57 pounds of nitrogen and 723.19 pounds of phosphorus out of the adjacent estuaries.