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.
--. Elwha River Ecosystem Restoration Implementation Summary Draft EIS (Apr. 1996).
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--. Elwha River Restoration Project, Washington: Sediment Analysis and Modeling of
the River Erosion Alternative, Elwha Technical Series, FN-95-9 (Aug. 1996). n. pag.
Online. Internet. 14 Aug. 2000. Available: http://www.nps.gov/olym/elwha/
reclamation/sediment.htm.
Winter, Brian D. Project Manager of the Environmental Assessment for the Elwha River
Ecosystem Restoration. Personal Communication. 24 July 2000.
--. The Importance of Marine Derived Nutrients for Ecosystem Health and Derived
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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.
The one feature common to the Hoover Dam, The Mississippi river and the three gorges dam is that they all tried 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.
When dams are created, such as the Glen Canyon Dam, their done so in hope to manipulate water flow for our benefit. These benefits, or positives come from a wide rang of categories. Some include hydroelectric power, controlled water supply, flood control, recreational areas for leisure activities such as boating and fishing. However, as we have progressed since the building of the damn in 1963, it seems we have dug up a lot more negatives than positives.
Energy production is the second major reason for the construction of Three Gorges Dam. China’s demand of energy has been increasing rapidly that the Government have to find ways to fulfill the huge demand. The Three Gorges Dam becomes one of the solutions in meeting the needs. According to China Three Gorges Corporation, the dam contains twenty-six turbines, each generating 700MW, thus ...
Yet, there is no such thing as “clean hydro power,” with the exception of very small-scale hydropower dams at the individual or neighborhood level. Hydro powered dams can cause major fluctuations in downstream flows, and even dewater the stream channel, leading to direct death of fish and other species. The main effects of a dam on a river is that it disrupts flows, lowers water quality, blocks the movement of rivers vital nutrients and sediment, destroys fish and wildlife habitat, and eliminates recreational opportunities. Reservoirs slow and broaden rivers, making them warmer, reducing water quality, and harboring destructive nonnative species that scatter throughout the watershed and prey on and compete with native wildlife. The environmental, economic, and social impacts of a dam and reservoir may run the entire length of the river from the highest mountain peaks that feed the headwaters to the river’s outlet at the ocean according to
Our use of science and engineering sets us apart from all other organisms. We are constantly modifying the land, oceans and atmosphere. It is estimated that we have over 2,500 dams in Michigan. Of the 2,500 or so dams in Michigan, only about 114 are utilized for hydropower production. According to the Department of Natural Resources, “Most of the hydropower dams and related facilities are regulated by the Federal Energy Regulatory Commission (FERC), with the exception of a few small projects that do not provide energy to the regional power grid.” In other words, although it’s a different form of energy that is beneficial to the environment of Michigan, the amount of hydropower dams is not enough to make a significant impact. The DNR go on to say the following: “Hydropower dams only provide about 1.5% of the power produced in Michigan because Michigan's rivers are relatively small and flat in comparison to the larger projects in Eastern and Western States. Altogether, the hydropower dams produce only about 400 megawatts of power. The 10 largest hydro dams in Michigan, only 10% of all hydro dams, produce about 47% of the hydropower in the State. Hydropower production is a very small component of Michigan's energy production and is unlikely to grow
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).
Outside of China, the United States is the most-dammed country on the planet. Counting only dams taller than fifty feet high, the U.S. has some 5,000 dams that range from giant hydroelectric dams such as the Grand Coulee in Washington State to flood control dams in the southeast and dams that provide water for irrigation in California. Overall the United States has as many as 2.5 million dams of one sort or another. The design and construction of many of these dams took place between 1930 and 1975. This 45 years period is known as the golden age of dam building, starting with the construction of the Hoover Dam beginning in 1931. By the 1970s the golden age of dam construction began to come to an end with increased concerns of the impacts of dams on their surroundings. To better understand this time period I will look at the construction of Hoover Dam during the 1930’s followed by an examination many of today’s arguments for and against dams [i].
Rivers all over the United States create geological features that fascinate many people, whether it is for work or for play. Rivers also pose a threat to many towns every year as spring rains and snow melt fill these rivers to beyond capacity, causing them to overflow their banks; flooding the surrounding areas. Rivers may cause floods, however, they also provide many benefits to society. One of the most notable is hydroelectric power, which often leads to a river being dammed. A dammed river creates a reliable location for adventure companies to establish whitewater rafting businesses that utilizes the flow of the river through rapids and scenic views to create a thrill for adventure seeking customers.
The federal government has taken action in requiring “each federal agency to review its dam-safety activities and to strengthen its dam safety programs” (Gunn, 2006). Dams are now required to be inspected annually, with a detailed report of the dam every three years (Gunn, 2006). Moreover, “Congress passed several acts authorizing a natural dam-safety program” which works to protect Americans from dam failure, in addition to installing more instrumentation to monitor the dam’s stability (Gunn, 2006). Sherard (1987b) proposes that having bureaucracies design dams is dangerous and should be avoided; Seed and Duncan (1987) added that it should be reviewed by an outside group of engineers to ensure that no possible design flaw has been over looked. The Teton Dam was an inadequate and unacceptably designed for this environment, and any unanticipated conditions and problems with materials, such as low quality, should be taken into account (Sherard, 1987b; Seed and Duncan, 1987). The wet seam was a new discovery and a lesson in the hydrogeologic properties that were a result of the situation created by the Teton Dam (Sherard, 1987b). An additional lesson is that filling the reservoir at the recommended speed, in controlled conditions is essential, so that it is possible to lower the
California is one of the most diverse and beautiful states in America with 223 different animal species and an estimated 6,300 native plants. Right now California is facing one of the most severe droughts ever to be recorded which is threatening not only all of us living in the Golden State but the plant and animals inhabiting it as well. Many say dams and reservoirs might be the answer to our problems. Being almost 35 years since the last dam was built in California, supporters are pushing for a new dam-building era. But, before moving ahead it's important to look to the past to see why California stopped building dams in the first place.
Subtractability is the degree of which the use of the good by one person reduces the good for the others. The use of a dam may be used for water supply in a section but then it reduces the water supply in other areas and causes blockage, which makes dams highly subtractable. This can cause a drought, which would cause farmers crops to not grow, which would mean less quality food for the community to buy, and less money for the farmers. This chain would keep going with negative affects and it shows everything in the environment is intertwined in some way or another. Although, dams would be helping some areas, they are harsh to the areas around them. Another issue caused by subtractability is the killing of fish. By using dams for resources such as electricity is helping some, yet it is blocking water passage and also the organisms that live in the water. Damnation spent a lot of the documentary analysing the dams in Washington’s lower Snake River. They said that many now see it as part of the landscape and are almost immune to it, they do not realise the dams and the issues it’s causing. An article from the Denver post stated that “The movie draws a bead on four 100-foot dams on Washington’s lower Snake River. Clogged with sediment and lacking any passage for native salmon, the dams generate little hydropower” (Blevins, 2015). Restoring habitat for fish needs to occur by the removal of dams, so the river flow can run smooth. It is estimated that “the global ocean has lost more than 90% of large predatory fishers with an 80% decline typically occurring within 15 years in industrialized exploitation” (Dietz, 2003). Building dams may be beneficial for the people who created them, but they have large disadvantages for other in the community and seems selfish to think about one’s advantages, rather than the negative effects it will have on the community as a
The Hoover Dam is one of the biggest dams and power plants in the world. It was built during the Great depression and continues to be a source of energy for the area. Between 1930 and 1936, thousands of people worked on the dam and ninety-six workers died from accidents directly relating to the building of the dam. It was the first human-made structure to exceed the masonry mass to that of the Great Pyramid of Giza.
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...
Many people have already dammed a small stream using sticks and mud by the time they become adults. Humans have used dams since early civilization, because four-thousand years ago they became aware that floods and droughts affected their well-being and so they began to build dams to protect themselves from these effects.1 The basic principles of dams still apply today as they did before; a dam must prevent water from being passed. Since then, people have been continuing to build and perfect these structures, not knowing the full intensity of their side effects. The hindering effects of dams on humans and their environment heavily outweigh the beneficial ones.