andating that at least portions of some specifically named U.S. rivers should remain free-flowing in perpetuity (Castillon 193). It is not clear that either president scored an ethical coup or committed an ethical sin.
Among the examples to be cited here, one cannot find a single dam, built for singular or multiple purposes, that was constructed as a weapon, to do harm or to deliver net evil; that is, as far as one can tell, there have never been unethical dams or dam builders. However, that dams have caused social upheavals and environmental disruptions at many U.S. sites and around the world is unarguable.
What are these upheavals? Hanes tabulated the "biotic impacts" and included the following upstream impacts: inundation, leading to "destroyed" terrestrial plants and "displaced" wildlife; new and more concentrated seasonal flooding that removes both topsoil and microorganisms; water quality changes in the pool (different from the previous river) regarding temperature increases, oxygen decreases, and sediment and nutrient entrapment; and denuded shorelines and water level fluctuations leading to the proliferation at the edges of "weedy species" or other less-than-desirable plant outcomes. He also named downstream impacts that include altered streamflow regime and quality and an altered ecology, resulting in lowered species diversity, and altered and sometimes wildly fluctuated water quality with respect to nutrients, temperature, and dissolved oxygen (7-14).
Hopwood listed the negative impacts at Aswan as follows: 1) Clear water from the dam no longer carries fertilizing silt; fertilizer value will have to be replaced; 2) water below the dam tends to flow more swiftly and erodes the bed; 3) fish life both in the reservoir and as far away as the Mediterranean may be affected; and 4) the chemistry of the river water has been affected such that choking growths of a water weed known as the Nile hyacinth have exploded, blocki...