Ukubalwa kwevolumu yamanzi ethangini elingakapheleli
Sibawa utjengise ubukhulu ngamamilimitha
D - ububanzi besitja
H - izinga lamanzi
L - ubude besitja
Ihlelo lizokubala umthamo wamanzi ethangini eliyisilinda, umthamo opheleleko nomahhala wesitja, kanye neendawo eziphezulu.