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Electricity
A clean and inexpensive source of nearly 20 percent of the worlds power
Industry
Hydroelectricity can create a focus for industrial development
Flood control
regulated water flows downstream
Reservoirs (1)
Water behind the dam is used for agriculture, industry, and recreation
Reservoirs (2)
habitats for fish and migratory birds
Transportation
Regulated water levels allow for cheap and barge transportation
Self-sufficiency
Hydro-electricity reduces dependence on imported fossil fuels