Following torrential rain on Thursday afternoon, a row of seven terraced houses in the Ballycolman estate were damaged again.
Residents said they felt ignored and frustrated that NI Water had not resolved the recurring problem.
Emma Relf’s home was flooded at the start of July and again on Thursday.
“All the downstairs floors, any mats, carpet, lino, wooden floor, the front door is warping, the wooden doors are warping,” she said.
“Us people that have got insured haven’t even got our claims through from the first time.”
A spokesperson for NI Water said that they sympathised with the residents of the Ballycolman estate but said that the sealed sewer system worked to its fullest capacity during the exceptional rain event on Thursday.