The Lagan Valley MLA said: “This mistake will hit householders very hard. They will have to pay 15% more than they previously expected. How come NI Water and the Executive did not spot this massive mistake earlier?
“So much for a fair system! This error shows that people are right to be suspicious about the Executive and are right to be cynical about their ability to deliver for Northern Ireland.
“The reasons for this dreadful error will not wash with local people. There are a number of important questions that NI Water and the Executive must answer regarding this sorry saga.
“I am sure that the Executive will soon be drowning in a sea of excuses over this awful mistake.
“Why does it seem that local people will never get a fair deal out of this Executive on water?”