Explain how overpumping leads to water scarcity in coastal areas.

Over pumping refers to pumping fresh water and reducing the level of an underground layer of water. In coastal areas, the lower underground layer of water is infiltrated with salt water, eventually increasing the salinity of the underground layer of water to the point that it is not drinkable. The scarcity of water in the coastal areas because the water in the coastal areas is not drinkable.