Environmental problems and countermeasures of South-to-North Water Transfer Project

At present, the Huang-Huai-Hai Plain has formed a relatively complete drainage system and accumulated rich experience in preventing soil salinization. The East Route Project of South-to-North Water Transfer Project still belongs to the nature of water supplement, and it will not cause secondary salinization of soil in the northern irrigation area under normal circumstances.

2. The schistosomiasis area moved northward.

According to the field experiment of Oncomelania hupensis living and breeding in the natural environment north of latitude 3315' and the practice of South-to-North Water Transfer Project in Jiangsu Province, it is proved that due to climatic reasons, large-scale water transfer will not expand the schistosomiasis epidemic area north of latitude 38.

3. Immigration environment issues

Since Danjiangkou Reservoir has flooded 200,000 mu of cultivated land and 220,000 immigrants (survey 1990), if all the immigrants are resettled locally, the environmental pressure in the reservoir area will increase. In addition to local resettlement of some immigrants, comprehensive measures can be taken to resettle immigrants in new irrigation areas to properly solve the problem.

4. Influence on hydrological situation in the middle and lower reaches of Hanjiang River

Water transfer130-14 billion cubic meters, accounting for13 of the runoff of Danjiangkou dam site, accounting for 22% of the runoff of Hanjiang River basin, which may cause changes in the hydrological situation in the middle and lower reaches of Hanjiang River. After taking comprehensive compensation measures, the adverse effects can basically be eliminated.

5, the impact on the middle and lower reaches of shipping

Water transfer1.30-1.400 million cubic meters, the water level of the river will drop by 0.6 to 1.0 meters, which will have a certain impact on shipping and water transfer along the river and can be eliminated after the construction of cascade hubs.

6. Influence on bed-building movement of downstream river.

Water transfer130-1400 million cubic meters (the diversion scale is 500 cubic meters per second) will reduce the number of days when 800- 1000 cubic meters per second appears in the middle and lower reaches of the Hanjiang River by about 20 days, and 1000-3,000 cubic meters per second by about100 days.