St. Lucie County Artificial Reef Update: Aug. 2020
The cleanup of Moore’s Creek continues. A priority of the St. Lucie County Artificial Reef Program is to clean waters entering the lagoon. Program volunteers have started another project to improve water quality and fish habitat at the 13th Street Bridge.
The 10th and 13th Street bridges over Moore’s Creek are easily accessible and shallow water underneath the bridges make ideal locations for volunteer work. The 13th Street project area, like the 10th Street project area has a firm compact bottom covered by a thin layer of muck. The oyster shell modules volunteers deployed at 10th Street helped to create a current that scoured the muck, revealing a sand bottom where submerged aquatic vegetation like tapegrass can be planted. Tapegrass is an excellent fish habitat and the Florida Fish and Wildlife Conservation Commission (FWC) has already started planting tapegrass in Moore’s Creek near 7th Street.
The organic muck sediments covering the sand bottom result from vegetation like floating water lettuce decomposing and sinking to the creek bed where they consume oxygen, reducing available habitat for fish. Over the last year volunteers have developed techniques to harvest the water lettuce, preventing it from covering the 10th Street project area
Other shared similarities between the 13th and 10th Street projects are that both are narrow and shallow. The 13th Street area is rockier, however with large boulders protruding above the muck. The creek widens to the east of 13th Street and volunteers have installed oyster modules to capture water lettuce before it floats downstream.
Volunteer efforts aid the comprehensive efforts of the City of Fort Pierce to maintain the creek. The city collects water lettuce from the creek and can modulate water level through a series of water control structures. Lowering water levels mimics the natural seasonal variability, helping oxidize the organic sediments and reducing nutrients entering the lagoon.
Preventing both organic and inorganic pollutants from entering the lagoon is essential in preserving fish habitat. Harvesting of water lettuce and changing water levels have permitted the city to maintain stormwater conveyance without treating the water lettuce with herbicide. Stormwater runoff containing sediments, nutrients, oil and grease from roadways, pesticides and herbicides from uplands properties, and other chemicals also needs to be treated before entering the lagoon.
Volunteers hope to create a small filter marsh along part of Moore’s Creek to help remove some of the chemicals delivered by stormwater runoff. Any constructed marsh must not reduce stormwater conveyance and cannot hinder the City of Fort Pierce’s ability to access the creek with its maintenance boat. If the City grants permission to construct the filter marsh, volunteers will seek help from the FWC, Florida Master Naturalists, and the Boy Scouts of America to design and install the marsh. Christa Stone, a local radio personality, is coordinating volunteer efforts and has already recruited local residents to help with various aspects of this project.
To learn more about Moore’s Creek volunteer efforts, contact Christa Stone at christa@mytcmedia.com or (772) 361-3614. For information on the artificial reef program, contact Jim Oppenborn, St. Lucie County Coastal Resources Coordinator, at oppenbornj@stlucieco.org or (772) 462-1713.
