A third sighted the newborn after coming down the drain on Monday, Garrith Jamieson, head of Durban Rescue Care, said in a statement obtained from CNN.
Rescue services used a chisel and a hammer to break into the drain, said Jamieson. The whole operation lasted almost four hours.
After being located and untangled, the child was transported to the Inkosi Albert Luthuli hospital for urgent care.
Dramatic video from the scene showed the moment when the child was brought to safety.
The child, who was found intact with his umbilical cord, was believed to have an age of one to three days.
Sibanisethu (Our Ray of Light) and Gabriella were called by residents, according to the statement.
"It is truly a miracle that this child was saved: the doctors gave this child a certificate of good health, and she will be transferred to another hospital," said Dr. Sibongiseni Dhlomo, regional health official.