Renewable Ocean Energy, Palm Beach Gardens, Florida (2010)

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1 POTENTIAL ENVIRONMENTAL IMPACTS FROM TAPPING ELECTRICAL ENERGIES IN THE STRAITS OF FLORIDA C.W. Finkl, R. Charlier & C. Makowski Department of Geosciences Florida Atlantic University Boca Raton, Florida, USA Free University of Brussels (VUB) Brussels, Belgium Renewable Ocean Energy, Palm Beach Gardens, Florida (2010)

2 PURPOSE AND GOALS Show relevance of ocean current Energy Production Units (EPU) along the southeast Florida coast Relate the configuration and environments of the continental shelf to cable laying scenarios Introduce geomorphological maps of the shelf interpreted from LADS (Laser Airborne Depth Sounding) bathymetry Indicate some potential environmental risks of transiting the continental shelf with electrical transmission cables Discuss possible solutions of potential risks to coastal marine environments caused by connecting offshore EPUs with the electrical grid onshore

3 OCEAN CURRENT GENERATED ELECTRICITY: RISKS AND VULNERABILITIES Failure of EPU (Energy Production Units) Maintenance of EPUs (e.g.. removing biofouling films and encrusting organisms such as barnacles) Hazards to submarines, migrating mammals and fishes Hazards to surface shipping vessels during maintenance Damage to sensitive coastal marine environments during installation ti

4 THE PROBLEM! Getting electrical transmission cables ashore from EPUs Crossing sensitive environments on the continental shelf THE SOLUTION! Learning how to avoid environmental impacts by laying electrical transmission lines ashore across (over, under, through) coral reefs and hard bottoms

5 STUDY AREA On Cusp of Nearctic and Neotropic Terrestrial Ecoregions L. Okeechobee EAA Adjacent to areas defined in the World Database on Protected Areas Florida Keys National Marine Sanctuary & associated aquatic preserves Aquatic Preserve of Biscayne Bay Particularly Sensitive Sea Area (PSSA) Everglades, Big Cypress Swamp Gulf of Mexico Big Cypress Swamp Source: Marine Environmental Protection Committee (MEPC) of the International Maritime Organization (IMO) Florida Bay Urban Sprawl Ocean to Everglades Dikes 7 million people

6 SE FLORIDA URBAN CORRIDOR Adverse impacts from over- populating sensitive environments Vast coastal wetland until post WW II Atlantic Coastal Ridge urbanized by early 1900s Encroachment of wetlands by mid 1900s 50% of Florida Everglades remains protected Today, 7 million people from Miami to Palm Beach! By 2020, population will be 10 million! They will need electrical energy from clean (green) sources Is ocean power the answer?

7 COASTAL CITIES MIAMI, FLORIDA This is why we need additional clean (blue) ocean energy! Intense Inner City Development Needs Electricity to Run

8 EXAMPLES OF OCEAN CURRENT GENERATED ELECTRICITY EPUs

9 Marine Current Turbines Ltd Installation and testing of the first commercial-scale monopile-mounted mounted experimental 300kW single 11m diameter rotor system off Lynmouth, Devon, UK.

10 The Dream Florida Hydro Energy Farm Popular Mechanics

11 Early in 2001 marine experts of United Nations organizations listed issues of global concern regarding deterioration of the marine environment: Eutrophication and anoxia Harmful algal blooms (HABS) Classical contaminants (e.g. sewage, metals, petroleum hydrocarbons) Deforestation Increased or decreased mobilization of sediments Demise of coral reefs Loss of wetlands Habitat destruction Climate change and sea-level rise Inundation as a consequence of physical alteration Increased risks to human health Reduced biodiversity Overfishing Exploitation of coastal mineral resources, particularly sand and gravel Litter -- GESAMP71:09

12 ZEE BIG QUESTIONS Can EPUs work in the Environment of the Florida Current? Let s assume YES so we can focus on environmental issues! Are the problems Technical? Environmental? Biological? Psychological? What are the vulnerabilities?

13 THE WATCHDOGS? United States Coral Reef Task Force Florida Department of Environmental Protection Florida Fish and Wildlife Conservation Commission i Southeast Florida Action Strategy Team (SEFAST) for coral reef conservation & management Southeast Florida Coral Reef Initiative (SEFCRI)

14 IMPACTS TO PELAGIC & Trawling for shrimp BENTHIC HABITATS? Pot fisheries for crabs Migratory routes for large mammals (e.g. whales, turtles) Schooling fish, sport fisheries Florida Reef Tract Inner continental shelf

15 REGIONAL SETTING SE Florida Atlantic Continental shelf is about 2 km wide at its narrowest point off Port Everglades (red arrow) in Port Ever- glades. Shelf drops off to 800 m depth after shelf break at m water depth. Narrowest part of the shelf lies between the two red bars marking northern and southern boundaries.

16 FLORIDA NORTHEAST ATLANTIC COAST 85 km Florida Current farther offshore and low population density onshore. 40 km The continental shelf along the northeast Florida coast presents few problems for bringing electrical transmission lines ashore because there are no coral reefs. The seafloor is dominated by sand waves and sediment ridges. The wider shelf requires that EPUs be located farther offshore, however.

17 STUDY AREA FOR EPU CABLE ROUTES Southeast Florida Atlantic Continental Shelf LADS SURVEY AREA PROVIDES DETAILED INFORMATION ON SEAFLOOR BATHYMETRY The LADS survey area covers about 600 km 2 in state waters along Palm Beach, Broward, and Miami-Dade counties. At its narrowest point, the continental shelf is about 2300 m wide off of Port Everglades.

18 Southeast Florida Atlantic Shelf Grand Bahama Upper Slope Biscayne Bay Shelf Break

19 LEGEND FOR SE FLORIDA ATLANTIC CONTINENTAL SHELF About 42 geomorphological mapping units grouped by Continental Slope Coral Reef (Florida Reef Tract) Hardbottom (Bedrock exposure) Sand Bottom Forms Tidal Features Applied to LADS imagery

20 RAW DATA COLOR RAMPED GEOMORPHOLOGICAL INTERPRETATION

21 LADS MAPPING PROCEDURE Window showing correspondence of mapping units with LADS imagery (bathymetry). Dredge Spoil Beach Ridges Sand Flat Diabathic Channels Sand Flat Sand Flat End of Drowned Beach Ridge g Plain Bahamas Fracture Zone B i i Beginning off Florida Reef Tract

22 HOW DO WE BRING AN ELECTRICAL TRANSMISSION LINE ASHORE? Example of how a surface cable might be laid across the shelf from an EPU farm in the Straits of Florida. Note that the cable enters the shelf through a reef gap and then follows an inter-reefal reefal sand flat, goes through another reef gap, then goes to Port Everglades via the navigation channel, and then to land. This example poses the fewest environmental hazards but creates other problems. Finkl, C.W., Leaky valves in littoral sediment budgets: Loss of nearshore sand to deep offshore zones via chutes in barrier reef systems, southeast coast of Florida, USA. Journal of Coastal Research,, 20(2),

24 THE PROBLEM WITH SURFACE ROUTES ON TOP OF THE SEAFLOOR There is no direct route from the EPU farm to the shore The cable route must pass through a reef gap Reef gaps do not line up between reef tracts Reef gaps do not line up with with breaks in hard grounds Cables laid on sand flats compromise future other uses of the sand resource, for beach renourishment for example The solution? Go underground with directional drilling UNDER the coral reefs and hard grounds

and out to sea on the slope From sea under

25 DIRECTIONAL DRILLING UNDER FLORIDA REEF TRACT From land under the continental shelf and out to sea on the slope From sea under the continental shelf and onto the land Conventional wire-line method and conventional equipment are used without modification. Fixing the direction of drilling can be done easily by electronic ec c multishot survey devices.

26 Southeast Florida Atlantic Shelf Grand Bahama Upper Slope Transmission Line Biscayne Bay Shelf Break Example of a transmission route from the Straits of Florida to land

27 DRILLING THROUGH LIMESTONE POSES POTENTIAL PROBLEMS Limestones are typically vuggy Holes and cavities in limestones may reach the surface of the coral reef Leakage of drilling fluids (lubricants and additives), muds (e.g. bentonite clay) can cause sedimentation ti on the coral reef surface smothering reef communities Solution holes Cavity connection with surface Cavities

28 IMPACTS OF DRILLING FLUIDS ON CORAL REEFS The skeletal extension and corallite shape of individuals id of the Caribbean and Atlantic ti reefbuilding coral Montastrea annularis (Ellis and Solander) were measured after more than six weeks' continuous flow-through exposure in laboratory aquaria to treatments t t of 0, 1, 10 and 100-ppm (l 1-1 ) drilling mud. Linear increase of the skeleton (extension rate) and fossa length were significantly depressed in the 100-ppm treatment. t t Chronic exposure to 100-ppm drilling mud impairs coral skeletal growth rate and possibly interferes with sediment rejection capability by lowering calical relief. Dodge, R.E., Marine Biology, 71(2),

29 EPA reports potential adverse impacts of drilling fluids and muds on coral reefs. But, presence of drilling muds must be present in concentrations ti greater than 100 ppm for four weeks or longer to damage coral reefs. There is potential for environmental damage to coral reefs from leakage of drilling fluids and muds, but waves and currents would tend to diminish possible impacts along the FRT.

30 CONCLUSIONS The future presence of EPUs in the Straits of Florida is a possibility The the SE Florida conurbation needs Blue Energy (Ocean Power Getting electrical transmission lines ashore poses environmental problems Geomorphological maps of the seafloor on the continental shelf will help determine the least damaging cable routes Cable approach routes will have to come ashore: (1) On the surface of the seafloor through Reef Gaps or Reef Gap Ramps (2) In Inter-reefalreefal sand flats and thence through hardgrounds (3) Underneath the FRT via directional drilling from land to the continental slope below the Shelf Break where shelf-edge edge coral reefs occur or (4) From directional drilling offshore through the face of the upper continental slope going under the FRT and outcropping on land

31 THANK YOU FOR YOUR ATTENTION

Regional-scale understanding of the geologic character and sand resources of the Atlantic inner continental shelf, Maine to Virginia

Regional-scale understanding of the geologic character and sand resources of the Atlantic inner continental shelf, Maine to Virginia Workshop on Dredging, Beach Nourishment and Bird Conservation Atlantic