Dredge Disposal, II: Computer-Simulated Growth of the Alcatraz Disposal Site

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This is a view of the bay floor over the dump site (yellow circle) south of Alcatraz Island as it appears today based on the newly acquired multibeam data. The disposal site is now a mound with positive relief above the adjacent bay floor. The vertical exaggeration of the island is 2x and of the submerged features is 10x. The gray mesh is 300 x 300 feet (91 meters).

larger version (51 kb)
This a north-south cross-section through Alcatraz Island the adjacent dump site. About 8.8 million cubic yards (6.7 million cubic meters) has accumulated in the area since 1894.

larger version (110 kb)
This is a computer simulation of the bay floor over the dump site (yellow circle) south of Alcatraz Island when it was partially filled. The vertical exaggeration of the island is 2x and of the submerged features is 10x. The gray mesh is 300 x 300 feet (91 meters).

larger version (100 kb)
This a simplified view of the dump site (yellow circle) south of Alcatraz Island based on surveys that showed a hole in the bay floor 50 meters (165 feet) deep in the area in 1894. This is approximately the natural morphology of the bay floor prior to dredge disposal operations. The vertical exaggeration of the island is 2x and of the submerged features is 10x. The gray mesh is 300 x 300 feet (91 meters).