Effects of bridge and culvert construction or replacement were studied on 41 streams in Tennessee. One 100-m stream reach above and two 100-m reaches below were sampled at each bridge or culvert with a 50-m buffer zone separating each reach. Fish communities were sampled bi-annually for two years following single pass depletion techniques using a backpack electrofishing unit. Sediment depth and silt-clay percentages were measured during the spring at the upper end of each 100-m sampling reach.