Boil Water Update – Where Are We Now?

The Grey District Council is working hard to investigate the cause of the April 8 water contamination, and says altered chlorine levels are keeping people safe.

The boil water notice for greater Greymouth was lifted last Friday.

Mayor Tania Gibson thanked people for their patience throughout that time

The council had professional, qualified staff working across it. The council’s draft Long Term Plan, which goes out for submissions later this week, would also look at some of these issues, Mrs Gibson said.

Work is continuing into possible causes of contamination.

Council group manager operations Kurtis Perrin-Smith said they were currently investigating every pipe break back to the start of April, and every repair.

They were also looking at leaks, as this was another possible way for contamination to get.

They were also looking at the treatment process itself. Staff do not believe this to be the case, but want to cover all bases. The fourth possible source is catchment contamination.

“It is possible we many never quite understand the point of contamination, but council has worked closely with (water regulator) Taumata Arowai to ensure we have got good barriers in place to protect against any future events.”

Currently, the council is dosing the drinking water at 2.4mg per litre (2.4 parts per million). Prior to this event, it was 2.0.

The new level meets the minimum requirements from the regulator. This direction from the regulator is permanent at this point.

The council has been unable to determine if the e-coli came from humans, or animals.

Mr Perrin-Smith said they needed a 1 litre sample to determine this. However, e-coli was only detected once during routine testing, at a very low level.

He expects to know more from the ongoing investigation by mid-winter.