Is South-to-North Water Diversion or Water Saving a Measure to Solve Water Shortage in North China? Why?

Saving water can't completely solve the problem. The shortage of water resources in North China is caused by overuse of groundwater, too large cities, too large population and too little rain and snow. Relying on the South-to-North Water Transfer Project can alleviate the water shortage problem, but it will be short after a long time, because some places in the south have also encountered drought and water shortage in recent years, and they are all using Yangtze River water. Therefore, on the one hand, North China should control the population expansion of big cities, and on the other hand, it should carry out seawater desalination technology in cities near the sea. Only multi-faceted efforts can solve the water shortage problem in North China. This is my simple idea, just as a joke!