Water is the basic need for the all the living things in different ways including the ecosystem in which we are all part of. The importance of water is well known. Water is our most precious natural resources. Its uses are innumerable and its importance cannot be underestimated. Its role ranges from domestic uses, agricultural and industry to religious, recreation, landscape decoration and even therapy. Water is basic to life. Due to the growing population over the decades, millions of people worldwide suffer from the lack of water especially in the urban areas where population concentration is very high. Because of this the demand of water is very high with overuse of ground water resulted in a drop in water table levels and have made the cost of water is high. It is found that rain harvesting, the collection of rain water from surfaces upon which it falls, is a long standing practice of many countries still use as a means for dealing with water problems of today. Rain is harvested in many ways and it is vital supplementary source of water. Diphu is the hilly town, the district headquarter of Karbi Anglong district, Assam, in the north eastern state part of India. The largest administrative district with over population of 61000. Located at an altitude of 186 m (610 ft) has suffered acute water problems, the mismanagement of the town committee, lack of proper knowledge on ground water potential areas has led the people suffered silently , pay a huge sum of money to buy a tank of water. This paper tries to attempt to understand the water scarcity problem’s as well the reason and the rainwater harvesting method practice by the local people. Keywords: water, scarcity, rain harvesting, population increase;