Over 70% of the Earth’s surface is covered with water, most of which is salty water of the seas and oceans. Fresh water that is required by land-based animals and plants in order to survive is only a small proportion of the world’s water, less than 3%. It can been seen that of the relatively small amount of fresh water present on the Earth’s surface, over 3/4 is frozen. Most of this forms a massive ice sheets of Antarctica and Greenland.
Distribution of water with respect to the location and density of population has always been the problem. Most of the world’s population(60%) lives in Asia which only receives 36% of the water which finds it’s way into the world’s rivers and lakes. 15% of the world’s freshwater flows down the River Amazon in South America, but less than 0.5% of the world’s population has access to this water. Two billion people around the world lack water that is safe to drink. Only one of the three of the world’s households is directly connected to a water supply.