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Below is a false color image of Debidue Island, where the colors on the image represent the data values — in this case, elevation. The term "false color" simply means that the image is not a photograph, and that you should use the color bar on the image to interpret what the colors mean. This image depicts the southern, undeveloped end of the island. The center portion of the island (out of this view) is armored against erosion. You can make a similar image using the BeachMapper software application provided on the second volume of this CD-ROM set. For more information about the BeachMapper Application, click here.
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Portable Document Format (PDF) maps have been created to show LIDAR data for South Carolina's beaches and islands. PDF maps will allow you to zoom in on the data and print the maps at better resolution. However, because of the intense density of the data, the PDF files will not draw properly from your browser. If you have Adobe Acrobat Reader® software installed on your computer, you can view the maps by navigating to the pdf/islands directory on this CD-ROM and double click on a file. A directory of maps is available in the readme.txt file. Adobe Acrobat Reader software has been provided on this CD-ROM.
To learn more about PDF documents and installing the software need to view them, click here.
In Georgetown County, Debidue Beach is situated between North Inlet to the south and Pawleys Inlet to the north and is the southernmost of the Grand Strand beaches. The central section of the island is armored with a continuous 4,500-foot long bulkhead. The beach at the base of the wall has been gradually lowering over the past several years. The intertidal and subtidal beach at station 4140 retreated by almost 100 feet between October 1994 and April 1995. South of the bulkhead the island is undeveloped and has experienced long-term erosion rates of -8 to -12 feet per year. The area north of the stabilized shoreline is stable to accretional. An 8,060-foot section of beach was renourished in 1990 with 192,000 cubic yards (cy) of inland sand hauled by truck from the DeBourdieu Colony development. In addition, 800 feet of the seawall was repaired from damage incurred during Hurricane Hugo and an artificial dune was restored. The most recent nourishment was completed in 1998.
Beach profile surveys are conducted in the spring and fall at approximately 400 monitoring stations throughout the State of South Carolina. Various agencies participate in the beach profile collection, including The South Carolina Department of Health and Environmental Control (SCDHEC) Office of Ocean and Coastal Resource Management (OCRM), Coastal Carolina University, and the College of Charleston. The results of the surveys provide a snapshot of the beach face. Over time, these surveys can be compiled to determine if and how the profile of the beach is changing. Below is a map of the stations and a sample of the profiles that can be extracted from the data. The beach profile data compiled by OCRM is provided on the second volume of this CD-ROM set.
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| *South Carolina Department of
Health and Environmental Control Office of Ocean and Coastal Resource Management |
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For more information about South Carolina beach profiles see: South
Carolina's Annual State of the Beaches Report, April 1998,
SCDHEC OCRM, 1362 McMillian Ave. Suite 400, Charleston, SC 29405.
| Beach | Debidue |
| Construction Dates | Late Spring 1990 |
| Completion Date | 5/1990 |
| Volume of Sand (cy) | 191,693 cy Reach 1: 104,341 cy Reach 2: 87,352 cy |
| Unit Area Volume(cy/ft) | Reach 1: 19.3 cy/ft Reach 2: 33.4 cy/ft |
| Source of Sediment | Inland sand hauled by truck from DeBourdieu Colony |
| Grain Size Characteristics Native Sediment/Fill | Native=0.26 mm (avg) Borrow=0.29 mm (avg) |
| Previous Nourishments | 1970s: Beach scraping and dune enhancement; 1990: Repaired 800 ft of seawall destroyed by Hugo; artificial dune restored |
| Length of project (Coverage) | 8,060 ft; Reach 1: 5,145 ft; Reach 2: 2,615 ft |
| % Sacrificial Fill | 40% beyond 5 ft depth (NGVD) |
| Total Cost | $855,000 (estimated) |
| Cost of Components | No Data |
| Cost per Unit ($/cy) | $4.50/cy |
| Funding | Private |
| Significant Storms | October 1994 Nor'easter |
| Storm Results | Failure of ~ 50 ft of seawall |
| Action Taken | Emergency repairs completed by early 1995 |
| Monitoring | Cubit Engineering, Ltd., 1981; Applied Technology & Management, Inc.; Olsen & Associates, Inc., 1986; CSE, 1989 |
| Engineer and Contractor | Coastal Science and Engineering (CSE)/ L.D. Weaver, Inc. (Pamplico) |
| Projected/Actual Lifespan | 5 years/4 - 5 years |
| Historic Erosion Rates | 3.75 cy/ft/yr entire island 9.00 cy/ft/yr on south end ~10- 15 ft/yr. since late 1930's |
| Beach Stabilization Structures | Existing seawall ~4,500 ft long, 14 ft high; installed 1981 by Cubit Engineering, Ltd. |
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