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Washington State , maintenance dredging conversion of shallower subtidal to deeper subtidal habitats is much more frequent than new construction dredging conversion of intertidal to subtidal habitats , which is rarely allowed . This includes the excavation ( dredging ) of channels , canals , ditches , lakes ; deposition of fill ; construction of docks , fishing and observation piers , wharves , mooring piles , dolphins , boardwalks , platforms , artificial reefs , navigational markers and signs , boat ramps , fences , dams , jetties , groins , dikes , bridges , utility lines , mines , salvage operations , including treasure salvage ; or other dredging or filling activities in or connecting to jurisdictional waters . There is a permanent dredging program of silted areas and an ongoing plan to recover populations of Chirostoma estor . On March 5 , 1904 , the American archeologist Edward H. Thompson , began dredging the Cenote of Sacrifice at the ancient Maya city of Chichen I in Yucan , Mexico . Two of his contracts included roofing work at Earle Naval Weapons Station and dredging part of the Shrewsbury River . Stephen Ramsey , the vice president of GE , said in reference to the EPA 's December 2000 statement that , " a massive dredging program of the type proposed today could be devastating to the ecosystem .