http://sanctuaries.noaa.gov/special/wellwood/project.html
M/V Wellwood Coral Reef Restoration
On August 4, 1984 the vessel M/V Wellwood grounded in the Key Largo National Marine Sanctuary which is now a part of the larger Florida Keys National Marine Sanctuary. This 122-meter, chicken pellet feed freighter logged onto the Molasses reef off of Key Largo. It rested there for 12 days due to removal complications. The ship had crushed 5,805 square meters of coral while another 75,000 square meters of coral reef framework had been altered. The place is now called the parking lot [B].
Technique
Assessment started the moment the news spread to the staff of the sanctuary. Assistance was given in how to best remove the ship without further destruction. Most of the corals affected by the grounding died because of the fiscal force and from the continuous shade during the time the ship remained. NOAA biologists did find a few of surviving remnants that had been dislodged were replanted [B]
Modules
22 reef domed modules were installed to heighten the sea floor shelf back to its original shape. A module is a hollow dome made from limestone held together with concrete. The weight was considerable at 3500 pounds apiece. The structure of this formation is reinforced by concrete slabs.
In the case of the concrete, biologists on staff were careful to create crevices and cavities for habitat. This was done by laying the cement mold with sand and limestone. After the cement had dried the sand was washed away.
At times a site had to be filled in before a module could be set in place. Care was taken have as much of the limestone at the surface without exposing the base [B].
In the case of the concrete, biologists on staff were careful to create crevices and cavities for habitat. This was done by laying the cement mold with sand and limestone. After the cement had dried the sand was washed away.
At times a site had to be filled in before a module could be set in place. Care was taken have as much of the limestone at the surface without exposing the base [B].
Site 21A on June 3, 2002
With a smooth sea the first module was lowered into the sea with a crane. 1 and 1/2 batches of concrete was pored to hold the structure in place. Stones were then placed in the surrounding area in order to blend in with the surrounding area.
BEFORE
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AFTER
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Site 1A on July 7, 2002
This site was particularly large and deep. Supports were made for 10 modules to raise them to the right height.
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Result
Five years after completion, a survey was conducted in 2007. The restored sites were compared with two unaffected nearby areas in order to establish a natural reference point. The amount of fish species counted in the restored habitat was 165 while there were 189 and 207 in the reference sites. Even though the M/V Wellwood destroyed sites are not as vibrant as the two natural settings the restoration improved the reef. The once devastated area is now able to provide habitat for species establishment [I].
