The full question:
“While boating on the Intracoastal Waterway I have noticed some of the dredge islands in our area have large permanent pipes running from the water’s edge back onto the islands. The pipes are approximately 24 to 30 inches in diameter and are secured in place with wooden pilings. What purpose do these pipes serve?”
And the answer:
The pipes release water from within the U.S. Army Corps of Engineers confined (diked) disposal areas and deposit it back into the Atlantic Intracoastal Waterway or other water bodies, Corps spokesman Henry Heusinkveld said.
“When dredge material is pumped into a diked disposal area, the deposited spoil material consists of approximately 80 percent water and 20 percent sediment. The water must then be slowly released from the disposal area through a structure called a drainage spillway, in order to allow time for the sediment to settle within the diked area rather than the material flowing right back into the AIWW,” Heusinkveld said.
Spillway pipes extend out from the dike walls to prevent the runoff water from disturbing or harming aquatic plants and animal habitats such as wetlands, marsh areas and primary nursery areas, he said.
Date posted: November 17, 2011
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