Sediment from bridge-pier or other in-stream construction work can cover fish eggs or damage young fish. It can also significantly reduce the ability of some species to forage and severely degrade their habitats. Thus, for projects requiring in-stream construction where protected fish are known to occur, the Tennessee Department of Transportation includes in the project plans a set of dates during which construction is not permitted. Each set corresponds to the spawning season for the particular species being protected. When contractors know these dates ahead of time, they can adjust their work schedules to complete the projects with little or no delay. Limiting construction activities to periods outside the spawning season has helped protect such threatened and endangered species as the boulder darter, the spotfin chub, Barren's topminnow, and the ashy darter.
--Apr 25, 2003