Question

Why there is shortage of water even through almost three forth of earth is covered with water?

Answer 1

Because there is only 3% fresh water available on the earth. 2% is present in ice brg
And 1% in lake ,pond, wells and etc.
That why there is scarcity.

Answer 2

There is shortage of water even though three fourth of the earth's surface is covered by water because all the water is not suitable for drinking as it is saline and not purified. Although we say 75 percent there is very little water which is fit for drinking which is available in the form of rivers, ponds, lakes, glaciers, etc and can be taken out from ground by wells, tube-wells and hand-pumps.