Examples of countries with a good water supply:
Great Britain, Germany, Austria, parts of Brazil, Parts of Canada.

Examples of countries with a bad water supply:
Ethiopia, Somalia, India.

The main problems with a poor water supply:
The land is too dry for agricultural use.
People have to walk a long way to collect water that isn't even clean.
There are problems disposing of human waste.
It stops countries developing; water is so important.