GICIA Mercabo Cove nearing completion

October 9, 2020
By Olivia Cameron

SUBMITTED BY THE GICIA- Construction at the GICIA’s Mercabo Cove site is nearing completion. TSI Disaster Recovery, the company hired to bring the Cove plans to life, is beginning to wrap up the final construction items. Construction began on March 2 and is anticipated to be completed by Halloween. The Cove project is designed to transform the basin area of the Mercabo Preserve into a marine sanctuary that will provide long-term benefits that include improved water quality, enhanced fish and bird habitat, reduced seawall maintenance costs and visually enhanced views of the preserve site. As of now, the reefballs, rip rap and reinforced concrete pipe (RCP) have been installed along the toe of the seawall around the site. All of these items are concrete and are used to reinforce the seawall while enhancing fishery habitat within the Cove. 
The RCPs that have been set vertically in front of the seawall will be used as planters for mangroves. As the mangroves grow, their root systems will extend over the tops of the RCPs, eventually hiding the concrete capsules. Once the mangroves have established a canopy, they will also provide shade for fish and roosting and/or nesting areas for birds. The living shoreline section of the project has also been completed except for final planting. 
Readily visible as you drive to and from the Island along the causeway, the east side of the entrance to the Cove has a section where the seawall has been completely removed. The remaining shoreline in that area has been stabilized with planted wetland grasses, and as it transitions into deeper water, reefballs have been installed. This shallow tidal area will create much-needed habitat for small fish, and the visual impact will be significant. 
The tidal pond was an addition to the Cove made after talking with Dr. James Locascio of Mote Marine Laboratory. The pond has been created in the most eastern section of the canal and has been constructed to mimic tidal ponds that are found along the southwestern coast of Florida and often used by locally important sportfish like juvenile tarpon and snook. The Cove’s tidal pond is tear-shaped and will be finished with a fringe of mangroves planted around the banks of the pond. Once the mangroves mature, they will provide a shady, shallow, safe area that is only accessible to small fish. 
The flushing channel and bridge, located at the eastern end of the dead-end canal, are two of the most significant features of the restoration. The flushing channel has been excavated to a depth that will allow tidal movement and significant water exchange between the Bay and the previously “dead-end” section of the canal. By encouraging tidal exchange in a section of the canal that has not seen water movement since the site was developed by Mercury years ago, water quality throughout the entire Cove system will be significantly improved. A rustic wooden bridge has also been constructed to allow access to the peninsula portion of the Mercabo Preserve site. 
Lastly, the planting of the Mercabo Cove project will begin in the next couple of weeks. Upland plantings will include nearly 600 mangroves and many other native grasses, trees and shrubs. Only taking a few weeks to complete, the installation of the native upland plants will make a dramatic difference in the aesthetics of the Mercabo site. And finally, the entire basin has been contoured (using local dredge material) to a maximum depth of four feet to ensure the appropriate depth for seagrass planting. The GICIA is excited to be working with Sea and Shoreline to plant nearly 3,600 units of seagrass, once the water in newly restored Cove has settled. Seagrasses are sensitive to water quality and are a terrific indicator of overall health of an ecosystem, which is why GICIA is so excited about the seagrass planting. Simply put, a successful seagrass growth will be assurance that the entire Cove restoration has been a success. 
Following planting, Sea and Shoreline will perform monthly maintenance as well as monitoring events to quantify seagrass survival, growth and project effectiveness. 
As many people know, the Mercabo site was once the home of Mercury Test Center. When the GICIA originally purchased the 30 acres it housed nine buildings including dry boat storage, a conference center, office, small hotel, and room for 185 wet slips. The GICIA’s initial vision for this site was to completely restore the uplands to create a visually attractive native bird and wildlife sanctuary that would be forever protected from development. Once the upland restoration was completed, the GICIA began to explore the possibility of creating an aquatic sanctuary, and the Mercabo Cove restoration project was born. This innovative project is estimated to cost $2 million, and the GICIA is extremely pleased that the Boca Grande community has continued to support the restoration of the Mercabo Preserve site. This unique project will provide enhanced habitat for juvenile snook and tarpon, the critically endangered smalltooth sawfish, and dolphin and manatee. If you would like more information on this exciting project, please contact the GICIA office at 964-2667.