Isithinteli sokubuyela umva sisetyenziswa ikakhulu kunikezelo lwamanzi ukusuka kwiyunithi yedolophu ukuya kwiyunithi yogutyulo jikelele logutyulo lunciphisa ngokungqongqo uxinzelelo lwemibhobho ukuze ukuhamba kwamanzi kube yindlela enye kuphela.Umsebenzi wayo kukuthintela ukubuya kwe-backflow ye-pipeline medium okanye nayiphi na imeko ye-siphon flow back, ukwenzela ukuba ugweme ukungcoliswa kwe-backflow.