Typically fishing is better, because fish will bunch up at dams while attempting to migrate upstream. Unfortunately studies show that dams contribute to the decrease of game fish and mussel populations and the increase of pollution tolerant fish populations such as carp. Dams block fish spawning migrations, and the buildup of sediment above the dams degrades spawning habitats for miles upstream.

Each dam is unique and requires an alternatives analysis or feasibility study to see what options are available. Removal is usually the least expensive option that not only makes the river safer, but also contributes to the river's overall environmental health. However removal tends to be controversial, because dams often have historical significance and tend to be better places to fish. Modification or retrofitting of dams may be expensive, but such projects do reduce the hazard at dams and often allow fish passage which improves the watershed's fishery overall. Some modifications remove blockage of the natural movement of sediment downstream. Some dams can be converted into whitewater courses that allow for varying forms of exhilarating recreation and economic development.