In ancient times people throughout the length and breadth of India learned that it was best not to depend solely on the rivers and lakes, which would dry up when the monsoon rains were over.
Iepriekšējās paaudzes saprata, ka nav droši būt pilnībā atkarīgiem no ūdens, kas uzkrājas upēs un ezeros, jo, beidzoties musonu sezonai, tie mēdz izsīkt.