On Wednesday, we removed more than 310 pounds of submerged trash from Manatee Lagoon, an area where hundreds of manatees will soon be congregating in cooler months to bask in the warm water outflow from Florida Power & Light’s plant in Riviera Beach, Florida.
While this area is important for manatees, it is also the location of two stormwater outflow pipes that drain rainwater from surrounding streets. Our underwater cleanup revealed that with this rainwater comes a lot of trash, especially plastic beverage bottles and aluminum cans according to a preliminary analysis of the debris. While LMC has not yet sorted all the individual trash items removed, some of the more unique finds included a roller skate wheel, a 2010 driver license, and a $20 bill.
This week’s cleanup was conducted by LMC staff in partnership with Manatee Lagoon and 4Ocean. Together, three divers, four freedivers, and a team of four on land worked for over two hours removing trash that had accumulated on the bottom of the lagoon. Even though LMC has conducted numerous underwater cleanups, this one was particularly revealing as to the types and amounts of marine debris that can be attributed directly to land-based sources via stormwater runoff. We noted that the debris seemed less weathered and broken down than the trash we find during our beach cleanups suggesting that it may have come from the pipes rather recently. The fact that we did not find a lot of these trash items covered with marine growth suggested that the debris at this site does not hang around for long but is moved from the lagoon by waves and currents and will eventually find its way to the ocean. It is estimated that nearly 80% of all marine debris comes from land-based sources.
In addition to conducting additional cleanups with Manatee Lagoon in this area, LMC will use the information to address the larger problem of land-based litter that is carried to the marine environment by stormwater runoff.