南水北调

　　中国的水资源，地区分布不均匀。总的来说南方多，北方少；东部多，西部少。随着人口的增加和经济的发展，北方缺水的情况日益严重，解决这一问题的办法之一就是跨流域调水，即南水北调。

　　南水北调工程包括东、中、西三条线路。

　　东线：从长江下游提水，沿京杭运河北送，可为华北平原东部补水。渠长1,150千米，每年引水量300亿立方米。东线不需要开挖新干渠，可利用已建成的江都、淮安抽水站设施和京杭运河，并且沿途有许多湖泊可作为调节水库。

　　中线：从长江中游及其主要支流汉江引水到华北平原西部。全长1,000多千米，每年引水量300亿立方米，其优点是引水量大，还可利用落差兴建水力发电站。

　　西线：从长江上游引水到黄河上游，主要为黄河上中游及西北地区补水。西线调水都在高山峡谷地区进行，海拔高，施工材料缺乏，交通不便，投资巨大。

　　三条线路可以互相配合，根据国家各阶段经济发展的需要和财力的情况分期开发。近期实施东、中线方案，西线是远景设想。

　　Water resources in China are unevenly distributed. Generally speaking, the south is rich in water while the north is short of this commodity; the same applies to east and west. With the increase of population and rapid economic development, the problem of water shortage in the north is getting ever more serious. One solution is to divert water from one drainage area to another, namely, from south to north.

　　There are three routes. The eastern line will carry water from the lower reaches of the Yangtze River northward along the Grand Canal to the North China Plain. It is about 1,150 km, and can divert 30 billion m³ water annually. There is no need to dig new channels along the eastern line. The facilities of the established Jiangdu and Huaian pumping stations and the Beijing-Hangzhou Canal can be used, and along the way there are many lakes that can be used as reservoirs.

　　The middle line will bring water from the middle of the Yangtze River and its main tributary, the Han River, to the western side of the North China Plain. It is over 1,000 km long and could divert 30 billion m³ of water annually. It can not only divert a large volume of water but also use the drop in altitude for hydropower.

　　The western line will divert water from the upper Yangtze River to the upper Yellow River to supply water for the upper and middle reaches of the latter and the northwestern regions. The western line will have to pass through mountains and gorges at high altitudes. Because of the lack of construction materials and inconvenient transportation, large investment is needed.

　　The three lines can be developed in stages according to need and the existing financial situation. For the moment, work is concentrated on the eastern and middle routes.