The Building of Dams
The earliest remains of dams that archaeologists have unearthed date back to around 5000 A.D.They were constructed as part of a domestic water supply system for the ancient town of Jawa in Jordan. Over the next few millennia, the building of dams for water retention spread throughout the Mediterranean, the Middle East, Southern Asia, China, and Central America. Later, as technologies increased and industrialization took hold in Europe, dam mechanisms advanced to incorporate watermills. With the advent of the water turbine in 1832 and developments in electrical engineering, the first hydropower plant began running in Wisconsin in 1882 (IRN n. pag.). Over the next few decades, while structural engineering techniques improved, dams multiplied in size, strength, and numbers worldwide.
Today, although the construction of new dams is halting ( albeit with less vigor in underdeveloped countries) (de Villiers 146; Pielou 206), they are still being built around the globe for a multitude of social and economical reasons: flood control, hydroelectric power production, river navigation, irrigation, human consumption, industrial use, emergency water reservation, tourism, and flat-water recreation (e.g., NPDP n. pag.; Trout Unlimited 11). For all the benefits that dams provide, however, there are adverse effects and concerns that arise from manipulating the environment in such an unnatural manner.
Impacts of Dams on the Hydrologic Regime
Dams are ultimately created as a water reservoir. This impounding of water impedes the circulation of a river and subsequently changes the hydrology and ecology of the river system and its contiguous environments.
Behind a dam, the rise in water level submerges the l...
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...s/feis1.htm.
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--. Elwha River Restoration Project, Washington: Sediment Analysis and Modeling of
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--. The Importance of Marine Derived Nutrients for Ecosystem Health and Derived
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There are nine dams in and directly leading to New York State’s Letchworth State Park. These dams have been built for a variety of reasons and affect nearly 400 miles of freshwater rivers in the Genesee River Basin of Western New York (Fish, n.d.).
Wuerthner, George. North Idaho's Lake Country. Helena, MT: American & World Geographic Pub., 1995. Print.
Silenced Rivers: The Ecology and Politics of Large Dams author Patrick McCully (2001) reports that dams store water for river fluctuations as well as for energy and water demands (p. 11).
The one feature common to the Hoover Dam, the Mississippi River and the Three Gorges Dam is that they all try to control nature’s swings, specifically in the form of flooding. Before the Hoover dam was built, the Colorado river “used to flood spectacularly.but after 1900 the Colorado provoked a vehement response” (Pg 177). The response was simple, but large. The U.S. built several large dams, including the Hoover dam, on the Colorado to decrease its flooding and increase power and irrigation. Unfortunately, just as human control of the Colorado’s flooding increased, its organisms and habitats were detrimentally influenced, and the water became more and more salinated.
The negative aspects of Glen Canyon Dam greatly exceed the positive aspects. The dam’s hydroelectric power supply is only three percent of the total power used by the six states that are served by the facility. There is a surplus of power on the Colorado Plateau and with more and more power-plants being created in the western hemisphere, Glen Canyon Dam’s power is not needed (Living Rivers: What about the hydroelectric loss). Although the ‘lake’ contains twenty seven million acre feet of water, one and a half million acre feet of water are lost yearly due to evaporation and seepage into the sandstone banks surrounding the ‘lake’ (Living Rivers: What about the water supply?). The loss of that much “water represents millions, even billions of dollars” (Farmer 183). If the government were to employ more water efficient irrigation practices, as much as five million acre feet of water per year could be saved.
A large issue we have that effects multiple different areas of our communities, are tragedy of the commons, which are actions that are rational but lead to irrational outcome. Government needs to take responsilbities to enforce rules for commons so they can diminish tragedy of the commons. Dams are a tragedy of the commons that only recently were come to the realisation of its more negatives effect they have on our world. Dams used to be seen as only positive, for their productful factors such as hydroelectricity and water supply. In this essay, I will argue that dams are an example of a tragedy of the commons proven by the documentary, Damnation, by the directors Travis Rummel and Ben Knight by describing that dams are highly subtractable
Over the years Glen Canyon Dam has been the spark for hundreds of debates, rallies, and protests. These debates have been going on for almost forty years now. The fact is that the dam created a huge lake when it was built, this is what bothers environmentalists. This lake is called Lake Powell and thousands of people depend on its tourists for income. The lake also filled up a canyon called Glen Canyon, some people say it was the most beautiful place on earth. The anti-dam side of the debate has its basis in the fact that Lake Powell is currently covering Glen Canyon. It was very remote so few people got to witness its splendor. This is probably the reason the dam was built in the first place, ignorance.
Based on the events that lead to the devastating floods in Queensland and the eventual case that was brought against the engineers of the dam, there have been views from both sides of the divide as to whether or not the actions taken by the engineers were actually ethical or otherwise. We have explored this avenue and have found that both sides of the divide have good reasons to justify their actions. Firstly, we shall explore the avenue that the engineers decisions were appropriate and ethical. It can be said that the engineers did employ act utilitarianism in their decisions and actions, hence causing these decisions to be ethically correct. Act utilitarianism is essentially doing the right thing, which would benefit the majority of people, based on the situation that is currently taking place. One of the reasons that explains why the actions taken could be considered as ethically fine, was that if the dam was not opened, there would have been no other way to solve the increasing water levels in the dam. If no action was taken, there could have been seriously devastating effects, like the dam wall eroding due to water spilling over the dam wall, thus weakening the structure, or a loss of water flow control. Professor Hubert Chanson, a professor in hydraulic engineering in the University of Queensland, mentioned that the Wivenhoe Dam was actually designed as an embankment dam, hence it should not be overtopped, that is water should not be allowed to flow over the limits of the dam (Andersen 2011). Despite there being a secondary spillway, however it is recommended that spillway is not put to use, as the use of that spillway would mean that there would be a surge of water leaving the dam, and a loss of control of the water flow, w...
The use of turbines from dams to provide power was a brilliant idea until water levels started running lower than normal. The water waste from humanity is directly contributing to portions of it, aside from drought conditions affected by pollution, widespread fires battled, and more adds to the depletion thereof. When humanity is relying on power provided from dams to handle the demand, they are essentially relying on the assumption that water levels will always be there to provide it. The Hoover Dam provides power to the southwestern portion of the USA that has a large number of people.
In the late 1800’s and early 1900’s, John Muir, a naturalist, and Marsden Manson, an engineer for the city of San Francisco, engaged in a heated debate over the construction of a dam in Hetchy Hetchy Valley. Muir wanted to preserve nature for the future, so he objected to the dam because he felt it would destroy the beauty of the area. On the other hand, Manson believed building a dam would provide water and electricity to the thousands of people who lived in the city of San Francisco, and this would preserve the well being of the human race for the future. Both men had good points and arguments to support their views; however, in the end you have to look out for your own kind. If there is a choice about the well being of the human race or nature, I believe there is only once choice to be made – the future support of the human race.
Pottinger, Lori. "Environmental Impacts of Large Dams: African Examples." International Rivers. N.p., 1 Oct. 1996. Web. 04 May 2014.
The first type of renewable energy is hydroelectric energy or well known as hydropower. In greek word, hydro means water and thus hydroelectric energy refers to electricity generated using flowing water at high velocity. Lutgens and Tarbuck (1992, p. 163) stated that “running water is of great importance to people as we depend upon rivers for energy, travel and irrigation”. Continuous availability of water in universe made water to be the main source of hydroelectric energy. Water has been widely utilized by mankind since the beginning of civilization and wate...
IYER, R.I. (19X9) "Large Dams: The Right Perspective.' Economic and Political Weekly, 14, 107- 116.
Impoundment is the most common type of hydroelectric power plant. In an impoundment facility, a large hydropower system uses a dam to store river water in a reservoir. When water is released from this reservoir it flows through a turbine, spinning it, and then activating a generator which conver...
first to be powered. In 1882, the world’s first hydroelectric power plant began operating in the United States in Appleton, Wisconsin.