Hydroelectric Power
The factors needed to determine the ideal location of a hydroelectric dam include the topography, a canyon that can be dammed, and an area to make a reservoir upstream of the dam. The infrastructure (basic building facilities and installations) required to develop hydroelectric energy is a dam, a hydroelectric power plant at the dam site to make power and the electrical grid for power distribution.
Advantages of Hydroelectric Power
Hydroelectric power generation does not create air, water, or thermal pollution. Once a dam is built the energy production is essentially free (except for maintenance) since the energy contained in water is being moved down hill by gravity.
Dams created for hydropower generation may create areas for recreational use for boating and fishing. Dams may also be used to manage flood control of an area if the dam release system is managed correctly.
Disadvantages of Hydroelectric Power
Placement of a dam changes the dynamics of a river’s flow and may alter the river’s ecosystem both upstream and downstream. Upstream habitats may be lost when a dam reservoir is initially filled. Dams can cause silt build up on the upstream side of a dam. Since the sediment is often trapped behind the dam downstream soils are not replenished. In addition, downstream riverbanks may become eroded when a dam’s floodgate releases water. Migratory fish such as salmon or shad must travel upstream to spawn. In some cases, dams with fish ladders may help these migrations. Dams without fish ladders restrict such fish migrations.
Commercial ships and fishing boats may need to find alternative routes around a dam system. Dam failures and accidents may affect populated areas located downstream of the dam.
