County flood-control workers may be forced to tear down 10 of the 16 debris dams on the South Coast because the National Marine Fisheries Service (NMFS) determined the dams could jeopardize steelhead trout, a federally endangered species. Five of the debris basins will have to be removed in the next 10 years. The remainder will have to come down or be modified after that. County Flood Control Chief Tom Fayram said the determination was made shortly after he submitted a 10-year plan for basin maintenance. Steelhead advocates have long objected that the dams disrupt the riparian environment on which steelhead rely.