Artificial rivers to help with rising water levels?

I know some people may call this stupid, possibly insane or impractical, but I feel I need to ask. what if people dug large rivers from the coasts of the continents inland, say, towards more dry areas like deserts or wastelands. It might also help in reducing desertification by allowing plants to grow near an artificial source of water. Again this may sound stupid to you, but it's the only idea I can think of other than just using nonpolluting technologies.