04 Jul 2007

Heavy rain and a rising river are to blame for residents in four Otago townships being urged today to boil all water for drinking and cooking. 

Dunedin City Council advised today that the Waikouaiti water treatment plant was "struggling to treat water to acceptable levels".

About 1600 residents in Waikouaiti, Karitane, Merton and Seacliff, north of Dunedin, were advised to boil all water until further notice. 

Council water and waste services team leader Gerard McCombie said today filtration technology at the treatment plant "struggles a bit" when the Waikouaiti River rose and became dirty.

"We've had a bit of rainfall in the catchments over the last couple of days and we just haven't been able to comply with the clarity rule for New Zealand drinking water standards," McCombie told NZPA. "So periodically we have to issue boil-water notices."

McCombie said the council planned to upgrade the Waikouiti plant and install new equipment late in 2008. "Hopefully the consumers will only have to put up with boil-water notices for another 18 months or so." 

Since the Waikouaiti plant was commissioned in the 1990s, drinking water standards had tightened considerably, making performance targets more difficult to achieve, McCombie said. "When we don't meet those targets we issue notices as a precautionary measure."

Council officers were made aware of the latest problem yesterday afternoon.