Ungqimba lokuzinza lwamanzi (ungqimba oluqinile lukasimende oluzinzile), olwaziwa nangokuthi ungqimba olungangeni manzi noma ungqimba olungangeni manzi, luyingxenye ebaluleke kakhulu yobunjiniyela bomgwaqo. Itholakala phakathi kwesendlalelo sokugcwalisa i-subgrade kanye nesendlalelo se-pavement, inhloso eyinhloko ukuvimbela ukufuduka phezulu kwamanzi angaphansi komhlaba kanye nomswakama, ukuqinisekisa ukuzinza kokugcwaliswa kwe-subgrade kanye namandla okuthwala okufanayo kwe-pavement. Izinto eziyinhloko ezisetshenziswayo ubumba, isihlabathi, udaka, usimende, i-steel slag nokunye. Lezi zinto zingasetshenziswa zodwa noma zihlanganiswe komunye nomunye ngokusho kwezici zabo ukuze kuzuzwe ukumelana kwamanzi okuhle nokuhlanganisa. Izindlela zokwakha ngokuyinhloko indlela yokuhlanganisa irabha, indlela yokugandaya nendlela yokufutha. Lezi zindlela zokwakha zinezici zazo, okufanele zikhethwe ngokuvumelana nesimo esithile sephrojekthi. Ungqimba lokuzinza kwamanzi luyisixhumanisi esibalulekile sokuqinisekisa ukuzinza nokusebenza komgwaqo. Nakuba kuwuhlaka lwesakhiwo olunganakwa kakhulu ngabantu, indima yalo kanye nomthelela walo kubalulekile.