Damn Dams? (Rough Draft)

Dams. Webster defines the word Dam as a barrier preventing the flow of water or loose solid materials such as soil or snow (www.merriam-webster.com). To the average person, one most likely believes that dams are a great tool to our society when trying to protect our environment. For example, dams can be a primary source of water for towns, cities, industries, and irrigation for crops. They provide hydroelectricity, which is an alternative source of energy to fossil fuels. They can aid in a town’s list of tourist attractions. Finally, they can control water flow in the event of a flood and in addition can provide areas of drought with water during the dry season. All of which are great reasons to construct dams. However, the average person might not know that dams prevent the natural flow of sediment through a river causing the downstream area to become narrower and more channelized, that some animal species depend on the flooding season in order to carry out various life cycles, that they prevent various fish from spawning, and create stagnant water areas that provide mosquitoes, snails, and flies to breed which lead to malaria. Lastly a geophysicist named Dr. Benjamin Fong Chao of NASA believes that he found evidence that large dams have caused a change in earth's rotation, due to the transfer of water mass from oceans to reservoirs. Chao stated that with the increased construction of dams, the Earth's daily rotation has apparently sped up by eight-millionths of a second since the 1950s (www.arch.mcgill.ca/prof/sijpkes/arch374/winter2001/dbiggs/enviro.html). In the following paragraphs, I hope to inform you of the types of dams that have been carelessly constructed without any consideration to the environment as well as solutions that take into account the needs of both our society and the environment in order to build the best possible dam.

The largest dam that exists in the world today lies in the Hubei Province of Southeast China in the middle of the Yangzi River. It is known as the Three Gorges Dam and it is in the midst of one of the greatest environmental controversies of recent years. CNN’s Bruce Kennedy reports that the Three Gorges Dam is listed as one and a half miles wide and over two football fields high that will create a reservoir several of hundreds feet deep and almost 400 miles long. It is reported that engineers judge the dam will enable 10,000-ton ocean-going freighters to navigate openly into China’s interior for six months of each year, opening a province growing with agricultural and man-made goods. Additionally, the Three Gorges Dam will produce enough hydropower turbines that are expected to generate large quantities of electricity to the extent of 18 nuclear power plants (www.cnn.com). However, with a dam this size, environmental issues are sure to follow. Along the Yangzi River, there are a lack of water treatment plants which are a major concern to environmentalist because the vast size of the dam will create higher concentrations of hazardous pollutants in the water due to slowing flow of water. Additionally, the large size of the Yangzi River causes large amounts of silt to be backed up above the dam which experts believe will build up and prevent the traveling of large ships upstream. If this is the case, it will negate one of the large reasons for actually constructing the dam. Most importantly, the government of China is estimating a relocation of 1.2 million people that includes 300,000 farmers. Farmers are being relocated from some of the most fertile grounds China has to offer to regions that aren’t capable of producing such crops. The Chinese government response to critics is that the dam will produce one ninth of the world’s electric production and that is a great alternative compared to the burning of 50 million tons of coal each year by the country (http://www.cnn.com/). They believe the pros outweigh the cons… but do they? I believe that the Chinese were wrong in building such a large scale dam, even with the great benefits it posses. Instead, a series of dams should have been placed all along the Yangzi River and compromises could have been reached between the government and the possible people who had to relocate.

In order for society to benefit and the environment to go hardly unharmed, certain criteria will have to be met. To date, efforts to battle the impacts on the ecosystem from large scale dams have endured little success because of the lack of attention being paid by governments, engineers, and society. In order for large scale dams to become less detrimental to the environment, people are going to have to start planning ahead while keeping a “green mind” as the major priority. Nonetheless, it is important to note that case studies have showed the impacts of reservoir creation around ecosystems have had little environmental success (World Commission on Dams). This then calls for smaller dams that are still capable of producing hydroelectricity. Instead of constructing dams in the middle of large flowing volumes of water, control the water early from the source at the water’s tributaries. Also, in order to let the native fish of the area travel to and from spawning sites, create fish passages for the migratory fish. Such passages would be better equipped for smaller dams. Flooding will have to be methodically released with a compromise between locals and the surrounding wildlife and ecosystems downstream. In order for this to occur, a good information base has to be mixed with early co-operation between design engineering team, ecologists, the surrounding cities, the government, and monitoring scientist (http://www.dams.org).

Growing awareness by governments and legislation are becoming more and more popular due to noticeable changes in the environment and local ecosystems. Parts of rivers, basins, and streams are now being protected from such destruction. Furthermore, governments are taking the time and money to help aid ecosystems through a “compensatory” approach (World Commission on Dams). While some areas around large dams will be affected, other areas will prosper by the efforts of conservation to rejuvenate and protect threatened and endangered species elsewhere. Such processes are now taking place in industrialized countries, but particularly the United States (www.dams.org).

In conclusion, there will never be a cut and dry answer as to how beneficial dams can actually be, but with a team of intelligent and caring people, compromises can be made between the public and the environment to ensure a better world for all.