Question

Why should dams and canals consider with areas less rainfall

Answer 1

near dams and canals there is more humidity so that they are the areas of less rainfall

Answer 2

Dams and canals are useful source of water for the domestic,irrigation purpose and  industrial process.

They are important source of hydroelectricity,river navigation,recreation destination for fishing and boating and they help during floods and famine.

People can rely on dams for whole year for drinking water and for various other things