Who can help me answer the advantages and disadvantages of the east, middle and west lines of the South-to-North Water Transfer Project?

Advantages of the eastern route: using the Beijing-Hangzhou Canal to deliver water, the construction is difficult and the investment is small.

Disadvantages: step-by-step pumping consumes a lot of energy, is easy to be polluted and has poor water quality.

Mid-line advantage: the terrain is high in the south and low in the north, which can divert water by itself, with good water quality and large benefit area, alleviating the water shortage in Beijing and Tianjin.

Disadvantages: the main diversion canal has a long line, a large amount of work, large inundation loss, many immigrants and difficult construction.

Advantages of the western line: large scale and wide benefits, providing sufficient water resources for the development of the western region and improving the ecological environment in the middle and upper reaches of the Yellow River.

Disadvantages: a large number of tunnels need to be dug, and the construction is difficult.