Tauranga City Council is assuring residents their discoloured drinking water is safe to drink, but some homeowners have resorted to buying bottled water because they dislike the way it tastes.

The council received about 20 complaints about discoloured water yesterday, with one resident saying the water had tasted of chemicals for a number of days and another that the water appeared "yuck and brown".

However, the council's communications officer Marcel Currin assured residents the water was safe to drink.

Council water service team leader Peter Bahrs said the discoloured water supply in Greerton and parts of the Avenues was caused when unauthorised contractors flushed at least four hydrants in Tauriko at once without informing the council.

That led to natural minerals that build up over time in the water supply pipes being flushed into the system feeding Greerton and the Avenues by sudden bursts of pressure, he said.

"Typically these are iron and manganese which are present in the source water and which settle on the wall of the pipes over time," Mr Bahrs said.

Such minerals were usually collected in a controlled manner during the annual mains flushing programme.

Council had received about 20 formal complaints by mid-afternoon, but Mr Bahrs said by that time the water supply was essentially back to normal.

Gate Pa mother of three Wikitoria Nuku, 35, said she and her family reverted to bottled water a week ago after growing concerned about their water supply.

Ms Nuku said their water had been discoloured for four weeks but became worse about a week ago and smelt strongly of chlorine.

"Our tap water is visibly brown, it's foggy and tastes funny, and also reeks of chlorine. Despite council's reassurance that the water is still safe to drink, I'm not convinced."

Ms Nuku said all her children were big tap water drinkers. Two of her children had complained of stomach aches and, while she suspected the water, the cause of the illness was unclear.

"I'd like council to take some more action, not just send out a press release."

Ms Nuku said she emailed council yesterday to complain but was awaiting a reply.

Mr Bahrs urged customers to inform the council if they were still affected. Householders were also advised to run an outside tap for a few minutes before running an internal cold water tap to flush the internal system before using hot water.

The use of fire hydrants was limited to fire service professionals or contractors who obtained prior approval and hold appropriate licences, he said.

Mr Currin said the council was reluctant to name the contractor because the council had not yet talked to them about what happened. "That's the next step. Today was about trying to establish where the problem was coming from."

Additional reporting Sandra Conchie

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