WATER CONTROL. “In the course of maintaining a mound, a colony will move about 250 kg dry weight of soil each year to the mound surface from deeper soil horizons. This corresponds to roughly eighty liters of water that must be invested annually to maintain the mound (mound growth will require more). Meanwhile, a generous estimate of the colony’s reserves of liquid water amounts to about fifty liters at any one time.”
https://link.springer.com/article/10.1007/s12304-016-9256-5