Aluminium in water prompts 'do not drink' warning in Waiouru

Residents in the central North Island town of Waiouru are being told not to drink their tap water after aluminium was found in a sample.

An emergency alert went out on Thursday night with a precautionary "do not drink" notice.

Civil Defence Manawatū Whanganui said boiling the water would not make it drinkable.

Tap water should not be used for drinking, making ice or food, brushing teeth or preparing baby formula.

Ruapehu District mayor Weston Kirton is warning residents and travellers passing through not to drink the water.

He said it was a disappointing situation.

"There will be water available, it might be bottled water or buying water might be the go.

"We ... apologise to the passing traffic and the local residents for this inconvenience."

Ruapehu District Council said there was a water tanker at Z Energy and at the Primary School, and people should bring their own containers.

Civil Defence said 5-litre water bottles have been sent to the Defence Force base for people to collect.

It said it expected lots of people to be travelling through Waiouru on Friday.

"There's a graduation ceremony at the army base, people going to and from Fieldays, and Waiouru is on SH1."

The do not drink notice was expected to be in place until Saturday morning.

The Defence Force said a power outage at a water treatment plant was the likely culprit for aluminium being found in the water supply.

The town in the centre of the North Island is the site of an army base.

The Defence Force supplies water to both the military camp and the surrounding township through an agreement with Ruapehu District Council.

A Defence Force spokesperson said a sample from the treatment plant showed aluminium concentrations at about four times the drinking water limit.

Levels in the reservoirs and pipes were expected to be much lower, but still above allowable level.

A power outage outage appeared to have affected plant controls for a water treatment additive, the Defence Force said.

The plant has been shut and is being flushed out.

People should not drink the water in the meantime.

NZDF said the health risk from consuming water with aluminium above the allowable limit for a short period was low.

"If you have specific health concerns, consult your doctor or Healthline 0800 611 116.

"People with severely compromised immune systems, infants, pregnant women, and some elderly may be at increased risk. These people should seek advice about drinking water from their health care providers.

"While efforts are being made to notify all affected people, please pass this information on to your neighbours, colleagues and visitors to the site.

Waiouru Primary School said in a post on social media it had been advised of the "potential issue" relating to the water supply.

Following discussions with the Ministry of Education and the board, the school would close all drinking fountains on Friday, remind students not to drink tap water and provide hand sanitiser in classrooms, it said.

"Please make sure your child brings a named water bottle to school tomorrow", the school said.

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