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 The Project

View of an undamaged coral spur adjacent to the grounding site depicting typical reef biota at Looe Key Reef.

The Grounding SIte

The Looe Key Reef area contains some of the most aesthetically valuable and heavily visited reefs in the continental United States. Looe Key reef was named for the remains of the British frigate the H.M.S. Looe, which wrecked in this vicinity in 1744. It is part of the Florida Reef Tract, the third largest barrier reef system in the world. In 1981, Looe Key National Marine Sanctuary was Congressionally designated. This sanctuary was formally incorporated into the larger Florida Keys National Marine Sanctuary in July 1997. The Florida Keys National Marine Sanctuary, managed by NOAA and the Florida Department of Environmental Protection, protects 2,800 square nautical miles of critical marine habitat, including coral reef, hardbottom, seagrass meadows, mangrove communities and sand flats.

Threats to the Environment

The deterioration of the marine environment in the Florida Keys is not a matter of debate. There is a decline in the number of healthy corals, an invasion of algae into the seagrass beds and onto the reefs, declines in fisheries and fish stocks, and an increase in coral diseases and bleaching. In Florida Bay, reduced freshwater flow has resulted in an increase in plankton blooms, sponge and seagrass die-offs and fish kills. Overnutrification of the nearshore waters from sewage is problematic. Over 4 million people visit the Keys annually, 70% of these spend time in the sanctuary, over 80,000 people reside in the Keys full-time--all cause some impact. Recreational vessel registration has increased six-fold since 1965. Damage, whether direct, indirect, intentional or accidental hinders the ability of marine life to recover from natural stressors.

The most visible and familiar physical damage results from the carelessness or, on occasion, the recklessness of ship captains, boaters, divers, fishermen, divers, snorklers and beachgoers. Over 30,000 acres of seagrass have been damaged by propellers. Direct impacts to resources also result from careless standing on coral, improper placement of anchors and destructive fishing methods. Over 19 acres of coral reef habitat has been damaged or destroyed by large ship groundings. Approximately 500 groundings are reported in the sanctuary each year. Without some intervention, the reefs in these areas are not able to recover the hundreds of years of growth, obliterated under the keel of a vessel. Without some physical rebuilding of the underlying structure, recruitment of coral and other benthic species is handicapped by geologic time as well as all the other stressors on the health of the reef ecosystems.

Fortunately, when a grounding occurs in a national marine sanctuary, NOAA can seek damages to cover response, injury and damage assessment, restoration and replacement of the damaged habitat or acquisition of equivalent habitat, and compensation of the public for the value of the damaged resources until full recovery.

In 1997, the University of Miami paid $3.76 million in natural resource damage claims for the R/V Columbus Iselin grounding, including a $200,000 civil penalty. The settlement includes funds for physical and biological restoration and monitoring of the Columbus Iselin site, as well as compensatory restoration and monitoring (such as grounding prevention) elsewhere in the sanctuary.


The R/V Columbus Iselin Grounding

The Injury (August 1994)

Just before midnight on August 10, 1994, the 155 foot research vessel, the R/V Columbus Iselin (Iselin), owned and operated by the University of Miami went aground on a spur and groove coral reef formation in the western portion of the Looe Key National Marine Sanctuary, now part of the Florida Keys National Marine Sanctuary. These spur and groove formations are among the best developed in the Florida Keys. The grounding site was 12.9 km off the southwest tip of Big Pine Key, Florida (24° 37'N, 81° 24'W).

R/V Columbus Iselin aground Looe Key reef in the Florida Keys National Marine Sanctuary. Note the suspended sediment produced by the grounded vessel.

The vessel and its anchor severely injured four coral spurs resulting in near total destruction of reef flora and fauna at the primary impact site. In addition to injuries at the final resting place, the vessel created widespread injury to surviving organisms and coral colonies throughout the grounding track. The grounding generated considerable coral rubble and ship debris that rested in the sand channels and on the damaged coral spurs in addition to dislodging and overturning massive sections of coral. Fuel had to be off-loaded from the vessel tanks to allow the vessel to float and be removed from the reef. The vessel remained on the reef over 38 hours until it was removed by a commercial salvor working under the direction of the U.S. Coast Guard and sanctuary staff at 2 pm on August 12, 1994.

Injury assessment site surveys after the vessel was removed indicated the Iselin grounding created six scars on the top of four coral spur formations. The injured spurs were created over 4,000 years ago as part of the coral growth in the Pleistocene era. The physical injury obliterated this structure in some places, and compromised the structural integrity of other places and increased the risk of erosion. The grounding destroyed 163.88 square meters of living coral and 338 square meters of the reef framework.

Along with the physical and biological damage there were also cultural and aesthetic losses. Dislodged artifacts were recovered after the grounding, altering their contextual value. The closing of the grounding site for ship removal, rubble removal and injury assesment resulted in lost services to non-consumptive activities such as snorkeling and scuba diving.

Response to Grounding

Vessel salvage (1994)

As soon as the incident was reported, FKNMS staff responded and remained on site until the Iselin was removed. They provided technical assistance to the U.S. Coast Guard and performed reconnaissance dives to assess the threat of further damage to the reefs. A commercial salvor, under the direction of the Coast Guard and sanctuary staff, removed the vessel.

Emergency biological triage (August 1994)

Immediately following the grounding, NOAA biologists thoroughly searched the area for coral communities that could survive if recemented immediately. Very few corals had survived the initial impact; however, those which did were salvaged and reattached onto nearby reefs.

Removal of coral rubble (Summer 1995)

Coarse rubble atop injured reef spur.

It is estimated that more than 400 cubic meters of dead coral rubble were created by the impact of the Iselin on the reef. This rubble posed a threat to the surrounding biological resources, as it moved around with the wave action and collided with nearby coral colonies and other benthic organisms such as sea fans and sponges. The rubble also buried nearby living organisms. Since it was unstable, the rubble posed a threat to benthic organisms that might settle on it only to be toppled and killed later. To prevent further damage, NOAA conducted an extensive rubble removal project during the summer of 1995. Several tons of rubble were removed and transported by barge to Miami, Florida. After the rubble was sorted, all reef rock larger than 7.62 centimeters in diameter was transported to Key Largo, where it is being stored for restoration of the site. The remainder of the rubble was disposed of in an approved disposal area.

Removal of ship debris (August/September 1994, September 1995)

During the grounding, several steel plates were sheered off the hull of the Iselin and left deeply imbedded in the sand channel. A large anchor and other debris were left after the salvage operation was completed. These items posed a threat to Looe Key Reef resources. The hull sections and the anchor were removed in September 1995 during the rubble removal operation.

Retrieval and conservation of exposed cultural resource artifacts (August 1994, September 1995)

During the initial survey of the damage, NOAA saw that several cultural artifacts from historic shipwrecks had been exposed when the overlying reef matrix was destroyed. These artifacts were surveyed by a NOAA archaeologist, collected, and secured at the site. Later, NOAA removed a sample of the artifacts. Artifacts were conserved according to the Federal Archaeological Program's guidelines for conservation and curation of maritime cultural resources. The artifacts are currently in storage at the sanctuary's Key West office.

Development of a proposed restoration plan (December 1996)

In response to the grounding and the subsequent efforts, NOAA developed a proposed restoration plan for the site. This plan drew on the experience gained from restoring other grounding sites in the area and outlined a preferred alternative for the restoration of the Iselin grounding site.

Settlement (December 1997)

The University of Miami paid $3.76 million in natural resource damage claims for the Iselin grounding, including a $200,000 civil penalty.


Subsequent Damage

Additional damage to the reef occurred as a result of an active 1998 hurricane season (e.g., Groundhog Day Storm, Hurricane Georges, and Hurricane Mitchell). The injury sites were severely excavated vertically, except one spur, which suffered a lateral loss of reef surface. On the same coral spur, a 15-foot by 6-foot piece of the reef broke off from the landward side. Overall, the storm damage has deepened and expanded the injury site due to scouring wave action. A site reconnaissance of the damaged area was prepared in August 1997, and bathymetric surveys of the site were completed in October 1997 and December 1998.

Satellite image from NOAA/NESDIS of hurricane Georges as the center passed over Key West, Florida on September 25, 1998. This hurricane caused significant additional damage to the Looe Key reef site where the R/V Columbus Iselin ran aground.

During these storms the vulnerable sub-surface was further scoured by storm waves. The impact of the storms, particularly Hurricane Georges, caused volumetric losses that almost doubled the loss from the original incident. This underscores the importance of being able to do restorations more quickly, despite stalled settlement negotiations or lack of available funds to do an entire restoration. Emergency stabilization of the coral substrate is critical to the prevention of further loss of reef material.

Restoration Plan

The extensive physical damage caused by the Iselin grounding (e.g., scraping, cracking of the underlying fossil limestone) led to extensive impacts on the habitat and biological resources of the area. Because of this, the focus of the restoration effort is on recreating, to the extent practicable, preexisting habitat, structure, depth, and surface topographical relief. This approach will allow benthic organisms to recolonize the area. The restoration will build on state-of-the-art techniques developed in 1995 at the grounding sites of the M/V Elpis and the M/V Alec Owen Maitland off Key Largo. Without the physical restoration efforts, the site is likely to deteriorate further due to storm damage and biological recovery would be extremely slow. After the reconstruction, adult colonies of the major resident benthic species previously present at the site (e.g., hard corals, soft corals, sponges, and sea mat) will be transplanted to the re-created reef substratum. The site will be monitored to assess the recovery and natural recruitment processes of both benthic species like corals and sponges, as well as fish populations.

It is estimated that the restoration will take approximately 4 to 6 weeks. Boulders from a South Dade County limestone quarry will be used. Use of a construction barge moored on site but off the reef tract will prevent collateral damage to the reef. All operations will be planned and performed according to Army Corps of Engineers and national marine sanctuaries permit requirements.

The proposed repair plan consists of placing limestone boulders in the four damaged depressions in the reef and then stabilizing the boulders with a tremie pour of concrete around the boulders. The limestone boulders used for the repair will range from 3 to 5 tons, with diameters measuring approximately 4 feet. The boulders will be bound together by the concrete to create a single unit at each site. A special inert type of concrete and a process called a tremie pour prevent concrete from flowing into the water. The construction firm will be employing extensive procedures to minimize turbidity. The restoration ultimately should reduce turbidity in the area by stabilizing loose sediments. Corrosion-resistant reinforcing fiber glass bars (rebar) will be placed in the concrete for improved attachment between boulder/concrete layers. Layers will be constructed one above another until the reef spur is restored. The large limestone boulders will create a topography similar to that provided by the reef spurs before the damage occurred. The sides and surface of each repair will include exposed surfaces of the boulders to enhance the opportunities for benthic recolonization of the repair area surface. The strength of the natural reef material is such that attachment of the repair to the natural reef by reinforcing steel would not provide additional stability. The repair will depend on the weight of each unit to provide structural stability in storm events.

Coastal Planning and Engineering Inc., is the design engineer for the physical restoration, and Team Land Development, Inc. is the construction contractor. Coastal Planning and Engineering, Inc. has extensive marine engineering expertise, including reef restoration work with NOAA's Restoration Center in Puerto Rico. Team Land Development, Inc. worked with NOAA on the Elpis and Maitland reconstructions and also did the rubble removal on the Columbus Iselin site.

Safety Concerns

Restoration work begins July 12, 1999 and ends September 7. (This time period includes a buffer for weather-related delays.) Because of the safety hazards posed by heavy equipment and construction activity, the sanctuary is asking the public to avoid the restoration site, located toward the western end of Looe Key.

Site Coordinates

24o 32' 40.3"N 81o 24' 30.6"W 24o 32' 42.3"N 81o 24' 24.5"W

24o 32' 46.9"N 81o 24' 26.3"W 24o 32' 44.8"N 81o 24' 32.4"W

Construction markers will outline the boundaries. The sanctuary will temporarily remove several mooring buoys (15-19) while construction is in progress. These buoys will be replaced after the physical restoration is complete.



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