Beauvilliers+-+Don't+Worry?

= Dams, a Study in Smart Sustainability = In 2002 an estimated 30,000-50,000 salmon died in the Klamath River in California. The death of these endangered fish was attributed primarily to the many dams in the river resulting in abnormally low water flow. Dams, particularly those used for hydroelectric power represent one of the oldest and most accepted forms of “green” power. However, in recent years, it has become increasingly clear that the green label of these structures, on any scale, is something to be questioned. Let them be an example of good intentions gone wrong but more importantly, let them remind us that we must think as broadly as possible when considering sustainability. We must keep in mind all the possible effects of our actions. As you will see, the effects of our actions can be innumerable and surprising.

First, some information about dams:
 * There are approximately 845,000 dams worldwide
 * Dams provide approximately 19% of the worlds electricity
 * Construction of the Three Gorges Dam in China, to be the largest dam in the world, will, upon completion, generate as much power annually as 50million tons of coal.
 * Dams obstruct 65% of ocean bound water worldwide

At first glance, dams seem inherently good. They generate electricity without the use of fossil fuels. They can prevent flooding. They can generate bodies of water for drinking, irrigating, and recreation. But unfortunately, this comes at great costs. I say costs plural because the effects of dams are vast. Many people are familiar at this point with the ability of dams to disrupt the lifecycle of fish, but few are familiar with many of the other effects they can have. Among them are the following:


 * Water projects, like damming, harm 91 percent of endangered fish and 22 percent of endangered birds in the United States alone.
 * The large bodies of water generated by dams cause stratification of life in those bodies into aerobic and anaerobic zones, the latter of which generates methane as a byproduct of the biodegradation of dead animal and plant matter. (Methane is a greenhouse gas)
 * Dams block the flow of sediments down river, negatively affecting growth of vegetation downriver and damaging many estuaries which rely on the nutrients carried from upriver.

However, these are just environmental impacts. Dams have social impacts as well. Many dams are located in rivers that travel through multiple nations but even those dams that are not placed in international rivers can have profound social impact.


 * As mentioned, the Three Gorges Dam in China will produce as much power as 50million tons of coal annually. But, to date, construction of the dam has flooded 13 cities, 140 towns, and 1,350 villages (intentionally), displacing 1.3million people.
 * Many dams in international rivers have caused tensions between nations, especially in regions like the Middle-East, where huge populations of people rely on the same water source (such as the Nile).

Closing words: While dams can be extremely useful, we must be wise about where they are placed and when we choose to use them. With the problem of global sustainability, people are often too eager to enact solutions to stand back and think about all the possible repercussions. For every problem there are many solutions and we must be critical in evaluating each to make sure we do more good than harm

McNally, Amy; Magee, Darrin; Wolf, Aaron. “Hydropower and sustainability: Resilience and vulnerability in China’s powersheds.” __Journal of Environmental Management__. (2009): 286-293 This article addresses many of both the environmental and social aspects of dams and their effects on local economies, cultures, and wildlife. It also does a good job exploring the international impacts of dams placed on rivers with international flow.
 * Sources:**
 * Primary:**

Pringle, Catherine; Freeman, Mary; Freeman, Byron. “Regional Effects of Hydrologic Alterations on Riverine Macrobiota in the New World: Tropical–Temperate Comparisons.” __BioScience__. Vol. 50 (2000): 807-823 This article focuses on the environmental impacts of dams, but does an excellent job referencing possible effects that are lesser known. “Klamath River.” Wikipedia. Feb. 7, 2010. . “Hydropower.” Wikipedia. Feb. 7, 2010. .
 * Secondary:**

“Dams, From Hoover to Three Gorges to the Crumbling Ones.” __Discover__. 2009. .
Beauvilliers, Evan