COASTAL SUSTAINABILITY IN THE FLORIDA KEYS Jennifer Hesson & Matt Williams December 22, 2007 University of Wisconsin - Madison CEE 514:  Coastal Engineering

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Proposal for Florida Keys Protection

After looking at the negative effects that groins, jetties, and breakwaters have on our coastlines and sediment transportation, we need to look at more natural ways and less intrusive ways to help protect our coastlines.  Barrier reefs have protected Florida's coastlines for hundreds of years, but are now dying from water pollution and human activity.  It is imperitive that something be done to mitigate the reef destruction to not only protect the shorelines, but protect the reef environment.  A new product has been developed, called reef balls, that is being used to replace the dying natural reef.  We are proposing that a long term solution to mitigate the pollution of the Florida Keys be developed, but as a short term solution, reef balls need to be implemented along Florida's coastline to protect the beaches and the reef environment. Barrier Reefs As mentioned earlier in the background portion of this site, the barrier reefs play a critical part in protecting Florida from wave activity.  The reefs act as a submerged breakwater that can dissipate wave energy and lessen wave impact on the shoreline.  In addition to this, the reef produces limestone.  This limestone builds up and is eroded by the waves.  Overtime, the sediment builds up and produces beaches.  In addition to protecting the coastline, reefs bring in revenue for surrounding cities and towns due to tourism. Since the reefs are dying at an alarming rate, something must be done to protect the reef now.  For years, sewage has been discharged into the ocean and now those effects are being seen.  This sewage problem must be mitigated to protect the reefs long term, but something must be done now.  Additional Information: Coral Reef Protection - EPA NOAA Florida Keys National Marine Sanctuary The Nature Conservancy in Florida Reef Balls Image:  Reef Balls sitting on coast before being lowered into the water. Image:  Reef Balls partially and fully submerged in the water off the coast. As seen in the image below, Reef Balls are artificial reefs designed to allow reef habitat to form in the ocean.  Reef Balls have been already been put into place in over 60 countries around the world, and each of these new envinroments has been monitored to see how the reefs will develop and how effective the Reef Balls are.  Reef Balls are produced from concrete in different sizes and shapes.  The concrete was specially engineered to be both porous, to support reef life, and very durable, so the Reef Balls can withstand waves and erosion.  The surface of the Reef Ball was taken into consideration to allow the most effective development for the reef on its surface.  Special consideration was taken into account in the design to ensure that the structure will not be toppled over when a wave hits.  The Reef Ball must either have a high bottom weight, or be anchored in some way to the ocean floor. The size and shape of the Reef Ball are dependent on the depth of the water and the strength of the waves in the area.  All of the shapes are designed to allow maximum cover for fish within the reef ball.   The protection offered will draw fish and reef ecosystems to the Reef Balls.  The center of the ball is also design to allow nutrients to be captured within the structure, this will help the coral to prosper on the artificial reef.  If only the concrete Reef Ball is placed in the water, it has been seen that it takes around 10 to 15 years for the structures to fully develop into reefs.  In addition to placing the bare Reef Balls in the water, designers have also used Reef Balls that have been already implanted with reef plants.  This will allow the reef to develop more quickly, and is helpful in quickly helping a natural reef that is in danger of dying.  These reefs can become fully populated in only 3 to 5 years after placement. Since Reef Balls are made with concrete, they are not difficult to produce.  The major problem that is encountered is the actual placement of the structure in the water.  The reef balls can simply be placed in the water using a barge and crane system, however, this can be an expensive process.  A more cost effective method of placing Reef Balls involves using an inflated bladder placed in the Reef Ball.  The structure is towed to the area of placement and divers slowly deflate the bladder and place the structure where desired. In addition to protecting the existing reef habitat, Reef Balls have many other advantages.  Since reefs produce sand, Reef Balls can be used to reduce the effects of coastal erosion on a beach, in addition to creating entirely new beaches.  Also, Reef Balls will act as a submerged breakwater.  Since these will be submerged, there will not be issues with aesthetics from the coastline.  The newly created breakwater will help to minimize the effects that waves have on the coastline.  Once the new reef is developed, the area will become a tourist attraction for fishing and scubadiving.  This will bring in revenue while protecting the ecosystem and the coastline. Addition Information: Reef Ball Foundation Reef Ball Pricing and Manufacturing