Water ran through 58 properties in Glen Eden on Friday, submerging cars and flooding homes.
The council on Sunday set up an emergency management centre after several residents pleaded for help.
Emergency response manager Clive Manley says the council sent out contractors immediately but it took longer to figure out which residents needed help.
He said a block of 17 flats was badly hit, though the majority of properties inspected had sustained only minor damage.
One family has been temporarily relocated while the damage is fixed and several others have left to stay with friends.
Mr Manley told Morning Report it is always possible to improve the way they deal with situations.
Contractors have been working on the broken storm water pipe, which should be fixed by Wednesday.