Sustainable water harvesting in India: A case study

This paper describes the results of a case study of one of the largest traditional water harvesting system in India. This tank is situated in Jaigarh, an old Fort in Jaipur. It is well engineered traditional water harvesting structure, with a capacity of 27,000 m3 of water suitable for drinking. The catchment area of water harvesting extends to about 4 km2 around the fort. In all, there are five tanks inside the fort. The largest and main tank is 48.1 m long, 42.06 m wide and 12.1 m deep and is covered. The roof of the tank rests on large arches supported by 81 pillars constructed inside the tank. The roof not only keeps the water clean but also checks evaporation. The study reveals that, for areas with an annual rainfall of 500 mm, a collection efficiency of 50% over a catchment area thirty times the tank size and an annual evaporation loss of 2 m, each tank will store water to a depth of 10 m. This traditional method can be used today when there is a great shortage of potable water.