Wells had been dug in the cities of the Indus – Sarasvati Valley by the third millennium B.C., while the “Great Bath” was probably a water storage tank.
Irrigation systems on the other hand spread over large open areas and had a complicated network of pipes and channels for collecting and distributing water. The melting snows and glaciers are the only source of water.
Trans Himalayan Region Water from melting snow and ice is the only source of water here. The people made intelligent use of their limited resources and made agriculture possible in this dry and barren land.
The water would flow from field to field and surplus water would drain back to the khud.
The kohli or water tender distributed and managed the water.
The natural slope of the land was taken advantage of to bring water from the river Ganga to the tank by a nullah.
The water first passed through two deep earthen tanks, where the silt settled down, and escaped through the upper end of the settling tank.
Rainwater is the only copious and clean source of water, but its distribution is neither uniform nor assured in all parts.
India receives about 400 million hectare metres (mham) of rain per year over an area of 329 mha.
A tank excavated at Sringaverapura near Allahabad, Uttar Pradesh, dates back to the 1st century B. Rama began his 14 year exile from here and could well have drunk water from this tank.