Intambo yaphansi, eyaziwa nangokuthi intambo yokuvikela umbani, ibhekisela entanjeni esetshenziselwa ukungenisa amanzi emhlabathini. Lapho imishini kagesi ivuza, i-current ingena emhlabathini ngocingo oluphansi, izinto zikagesi ezinamandla amakhulu zidinga ukunakwa okukhethekile.
Umsebenzi wayo ukungenisa ngokushesha amanzi emhlabathini ngocingo oluphansi lapho okokusebenza kwakho kukagesi kuvuza noma ukushajwa kwe-induction, ukuze igobolondo lempahla lingasakhokhiswa, okuqinisekisa ukuphepha kwabasebenzi kanye nezisetshenziswa.