Question

what is mean by channelling the flood water?

Answer 1

Flood control channels are large and empty basins which let water flow in and out (except during flooding) or dry channels that run below the street levels of some larger cities, so that if and when a flood occurs, the water will run into these channels, and eventually drain into a
river or other body of water...
hope it will help U

Answer 2

Flood water channels are large and empty basins which let water flow in and out (except during flooding) or dry channels that run below the street levels of some larger cities, so that if and when a flood occurs, the water will run into these channels, and eventually drain into a river or other body of water.