Ecological Protection

Man can survive without electricity, but not without water. The reservoir may change the climate of surrounding areas. The temperature of summer and winter may drop and rise by about 2 ℃ respectively. This change is more favourable to the growth of tung trees, orange trees ,chestnut trees,mulberry trees,etc, which need a warmer climate to live through the winter. Most of the rare and endangered species of plants are distributed in the areas above EL300 meters, far above the maximum flood level,and only very few rare and endangered animals inhabit the areas to be inundated. A study shows that the construction of the TGP will have no adverse effect on the living conditions of Chinese dolphin,Yangtze alligator,giant sela mander, etc .As we all know,the Gezhouba Dam caused a problem for Chinese sturgeon .They used to swim all the way upstream to spawn and then back to their traditional habitat,but the Gezhouba Dam blocks their way.This problem was successfully solved when the sturgeons began spawning naturally in the neighbourhood of the Dam with artificial breeding.The alleviation of flooding along the river's middle and lower reaches may make it easier to eliminate oncomelania and snail fever. The reservoir will regulate water storage and discharge for the need of navigation .Thus downstream flow will be increased during the dry season, but without causing any change in the underground water level.Therefore the swamp process of the valley will not be aggravated. According to the design,the reservoir is expected to store water in October,which will result in reduced downstream flows.But in years of ordinary water flow ,the river's flow is still higher than necessary to control salt content in Shanghai district.During the period of low water when sea water makes its most serious increase,the increase in regulated flows by the dam will have the obvious effect of diluting salt water and reducing salt content.it is estimated that after the completion of the Three Gorges Project,the desalination process of the soil in the river's estuary and surrounding coastal areas will continue and the water body will be more nutritious.

The construction of the TGP will not bring Chongqing under the threat of flood and sediment deposition.According to scientific experiments ,even the highest flood level occuring at a recurrence intervals of 1,000 years will not exceed EL 200 metes of the elevation of Chongqing's Chaotianmen Harbour,while the elevations of the urban districts are all above EL 200 meters.On the contrary,the port conditions will be improved without considering the construction of check dams on the main course upstream Chongqing even in 100 years.Being a river-type reservoir with an altitude difference of 120 meters and low sediment content(only 1/30 that of Yellow River), and on account of the operation policy of "Storing the clear and discharging the turbid",namely "Still water for navigation and torrential water for sediment discharge(which is operated mechanically),it can keep 92% of its regulating storage capacity in 100 years.Along the 1300-kilometer-long reservoir,there exist 22 potential site of landslide,with a total volume of 0.38 billion m3.Even if all of them slided into the reservoir ,they would only take up 0.9% of the total storage capacity. The Dam will be built on granite bedrocks which extend 110 km along and 70 km across the River. Furthermore it is designed against earthquakes of magnitude 7,which will protect the Dam from damage of any natural earthquakes or quakes induced by the reservoir,which, it is estimated ,will not exceed magnitude 6.As a result,the Project will act as the guardian for the protection and improvement of ecological environment of the Yangtze Valley.