Olympic medals 2020
Awards for the Tokyo Olympics will be made from elements of old electronic gadgets
Humanity has always sought to curb nature and subjugate its unlimited power. Dam construction is one of the attempts that people made for the first time thousands of years ago.
Centuries have passed and today dams are an integral part of the energy complex of almost every developed country in the world. Until recently, hydroelectric power plants were considered the most environmentally friendly way to generate electricity. Indeed, compared to coal-fired power plants, they do much less harm to the environment.
Monticello Dam in the USA, photo WEB
However, they can not be called absolutely safe. The construction of any dam is carried out while trying to balance the economic benefits and environmental safety, but as practice shows, this can not always be achieved.
The construction of the dam is associated with the flooding of adjacent territories, resulting in the loss of arable land and other areas of historical, archaeological and geological value. So, for example, in the US was completely flooded the most beautiful canyon, which was the habitat of hundreds of various animals species. In Tennessee, a unique historical monument - an ancient settlement of the Cherokee Indians - disappeared beneath the water. Moreover, in Egypt, the emergence of an artificial reservoir caused the epidemic of schistosomiasis.
The dam on the river Tennessee, photo WEB
The dam is an insurmountable obstacle to the passage of fish, which adversely affects their populations. In addition, even a short-term stagnation of water affects the life of all river inhabitants and animals living near rivers. Do not forget that along with the local increase in the level of surface water, the groundwater level also rises, which contribute to the erosion of the coasts and lead to landslides.
These problems rarely worry the inhabitants of megacities, consuming electricity from hydroelectric power stations, but there are other factors. Thus, accidents on dams in recent years have claimed hundreds of thousands of lives and caused damage, measured in millions of dollars. For example, in 1959 the dam collapsed in France. The whole city was flooded, and the damage amounted to about 70 million dollars. The cause of the disaster were errors in the design and unjustified savings on materials.
Breakthrough of the Dalnerechensky Dam, photo WEB
But it happens that the monumental structures built with a huge margin of safety are also unable to curb the elements. Thus, in the Italian Alps, the breakthrough of the dam in 1968 was caused by abnormal rains. The result is 2,500 dead. Modern buildings, too, can not always restrain the wrath of nature.
For example, in 2010, torrential rains caused a breakthrough in the dam in China, due to which one suffered ... 29 million people! And the disaster that happened last year in California is still fresh in memory of 200 thousand people who have left their homes in fear to save their lives.
Dam in China during heavy rain, photo WEB
In order to point out to humanity the potential and real harm of dams, in the spring of 1997 the American eco-society "International Network of Rivers" gathered a forum against the construction of large dams, held under the slogan "For rivers, water and life!". The meeting was attended by delegations from 20 countries, including the Russian Federation, the United States and China, who supported the initiative to approve a special eco-holiday.
Since then, the International Day against Dams (International Day of Action for Rivers) is celebrated every March 14 in various parts of the world. By this date, activists are preparing thematic events, seeking to attract public attention to existing problems, but little action has been taken so far. In some countries, the possibility of approving laws prohibiting the construction of large dams is being considered, in others obsolete structures are being dismantled, but no more.
In all of Europe only one river is free of dams - Pechora, photo WEB
Today there are thousands of dams on the planet. The highest (304 meters) is located in Tajikistan and is part of the Nurek hydropower plant. The second highest is on the Mekong River in China. Many dams, such as the Hoover Dam in the US, seem to attract tourists with its power and the beauty of the reservoir ... But this beauty is dangerous. To date, no major rivers left free from the source to the open water. In all of Europe, only one river is free of dams - Pechora. In total from almost 200 large rivers in the world unregulated there is only one third left.
Victoria Romanova, Russia, Moscow