why water has bcom a economic commodity

As we know that water is a natural resource. 75% of the earth surface is covered with water. However, out of this only 3% is drinking water. With the growing population the need of water has increased considerably in relation to its availability. Moreover, due to climatic changes around the world, various water bodies such as rivers, lakes, etc. are drying up. In addition to this, the industrialisation and the urbanisation  has led to the water pollution. As a result, the quality of the water has deteriorated and thereby, the availability of water that is fit for drinking purposes has reduced even more. It can be said that today availability of water falls short of its growing demand. Thus, it is due to its growing scarcity in relation to the demand (in alternative uses) that water is becoming an economic commodity.