Rainwater Harvesting in Kathmandu Valley

The table 1 shows the minimum water requirements for different household activities in an urban area.However, due to the intermit water supply and limited water availability the distribution of water is notuniform in most places. Some places receives plenty water where as others do not receive any water at all.The above table shows that most of the water in an urban area is spent in cleaning and washing, where asonly three litres is needed for an individual for a day. There are many places in Kathmandu Valley wherethere is not that much supply of water also. On the contrary, industrial sectors consume much more water.Even though, the supply is very limited, many household in Kathmandu Valley usually a toilet flush of 12-15 liters capacity, which normally uses fresh water from the municipal supply or groundwater, extracted with centrifugal pump. If the harvested rainwater can supply this much water, around 70-80 liters of fresh water can be saved per day in a house of five family members. Also cost of electricity to run pump can besaved. If the water collected is clean, it can be used for other household purposes besides flushing toiletand water supplied from municipal supply can be used for drinking purposes only.The fact is that the State has been unable to provide even the minimum drinking water to its residents inmost part of Kathmandu Valley; on the other hand the lifestyle of people is changing affecting their waterconsumption habit. The water demand of an individual household is increasing while water supplied isdecreasing. In parallel, the population is on increase and the question remains as to when the residents of Kathmandu Valley will have sufficient drinking water? If not what are the alternatives?