On Water Environmental Influence From The Comprehensive Reclamation Of Weihe River At Xianyang Section

Considering certain existing problems in the Weihe River drainage area, a short-period programme has been lunched by the Water Conservancy Committee of Shanxi Province as a general plan for recent years(till 2010). Aiming to restore the ecological environment and to restore the river bed, the Comprehensive Reclamation of the XianYang Section is one part of the general plan. The whole programme will include1)the restoration of the river bed; the construction of a rubber embankment to form a touring dam; afforestation and beautification of the beach land after the construction of the dam. The effort will help to form an artificial ecological system instead of the older natural ecological system so that garbage dumping, weeds, as well as sewage will be eradicated from the river basin, and the entire landscape on the Weihe River will be greatly improved in the end. In the meantime, the programme will have certain effects on the whole environment in many aspects, such as regional aquatic environment, ecological environment, flood prevention, diversity of pieces, co-ordination of ecological environment, botanical and zoological resources, soil erosion, land exploitation and landscape aesthetics, etc.According to the criterion and indexes proposed in the study made on the feasibility of middle reaches flood prevention on the Shanxi section of Weihe River, now the XianYang section is well under construction. The northern embankment is worked out for the worst possible flood in 100 years with a discharge rate of 9170 cubic meters per second, while the southern part is for 50 years and the rate of discharge is 8160 cubic meters per second. All this has been based on a careful study of the river basin and the flood season operation procedure by concerned institutes, meanwhile, the present water level has been rechecked and the water level after the construction has also been worked out.As an essential factor in actual operation, water resource feasibility for construction water restoration will be assessed from several aspects, including water volume, quality, sand and soil accountability as well as economical feasibility, etc, so that the water resource proposed in the contract will be properly argued and proved. Further more, concerning the likely oxidization of static waters and a consequent decline in water quality, assessment will be accordingly made on its renew ability and compensation efficiency, and certain principles...