南水北调引汉总干渠工程布置

General layout of middle route S-to-N water transferring canal

南水北调中线总干渠始于汉江丹江口水库库边的陶岔闸，经南阳盆地、黄淮平原及黄海平原西部，沿线送水并达北京和天津。５０年代中期便开始进行总干渠的踏勘选线、规划设计，已有较成熟的工程布置方案。总干渠工程由渠道及渠系建筑物组成。渠线（全长１２４０公里）。渠首陶岔闸后水位１４７．２米（黄海标高）北京玉渊潭（水位４９．５米），总落差约９８米，可实现全线自流；渠系建筑物８２０余座，类型繁多，主要为河道与渠道的交叉工程。由于历史原因，自总干渠分水的天津干渠．以选定白洋淀以北新开渠为推荐方案。

The main canal of the middle route S-to-N water transferring project originates at Taocha sluice bringing water from Danjiangkou reservoir on Hanjiang river,traverses the Nanyang basin,Yellow river and Huaihe rivet plain and finally terminates in Beijing-Tianjin region.As an outcome of a long-term investigation-planning-design since 1950's,a relatively well justified layout plan is presented.The total length of the main callal is 1 240 km and the total drop about 98 m(with a water level at Taocha sluice 147.2 m above msl of YelloW sea and that at Yuyuantan in Beijing 49.5 m).Under this condition the main canal will convey and distribute water all by gravity.There are more than 820 structures of various types in canal system. Most structures are at intersection of canals and rivers.Due to historic considerations a new stretch of canal is recommended to be built north of Baiyangdian for diverting water to Tianjin.