The Environmental Impact of Water Reservoirs Essay

918 Words 4 Pages
[A water reservoir is a human-made lake that is created when a river is dammed to serve one or more purposes, such as to generate hydropower production, provide a water supply for drinking, irrigation, and flood protection] (www.eea.europa.eu). The effects of water reservoirs on the environment have stirred controversy since their introduction. Though water reservoirs can create many sought out improvements for a society it can detrimentally impact natural habitats and spawn a number of environmental complications. The debate on whether water reservoirs are truly beneficial or harmful towards human populations is ongoing as new projects like the Three Gorges in China are concluded. In the following essay I will be giving a critical …show more content…
The ecosystem is changed dramatically, especially in areas that depend on natural flooding. When rivers are imposed on by a dam they naturally have reduced flooding. Though less flooding may be a positive for some social aspects it means a reduction in wildlife that is affected by the dwindling water source. Dams also hold back sediments that are utilized to replenish downstream ecosystems. Many native species may not survive these changes and in turn new species may be adopted into this altered habitat: virtually creating new unnatural ecosystems. Since dams change the ecosystem it almost always will result in a reduction in wildlife diversity, and can in turn mean the loss of many living organisms. To further gauge the impact a reservoir has on wildlife we must see how it obstructs animal’s needs. A dam creates a barrier between the upstream and downstream of a river affecting surrounding creatures. For example, in Sri Lanka the five-dam Mahaweli megascheme cut off an important migration route for the elephants and they have now become pests for the farmers who moved into the area (www.internationlrivers.org). In the case of salmon and trout their breeding patterns become blockaded. Since they are blocked off of their yearly migrations, they suffer a decrease in their reproduction, which subsequently reduces their population.
Reservoirs sedimentation is also a severe issue. Rivers are meant to carry different types of sediment downstream to form riverbanks,

Related Documents