Council’s chief says public safety was never threatened ... but reporting procedures must be examined

A review into how the public and local politicians were kept in the dark about a herbicide scare that closed two Hunua Ranges dams feeding Auckland's water supply has begun.

Auckland Council chief executive Stephen Town yesterday backed the actions of Watercare Services to ensure public safety was never at risk after traces of the herbicide metsulfuron-methyl were detected in the dams' water.

"I am confident that proper safety procedures were in place and were followed by the parties concerned," he said.

But Mr Town acknowledged concerns that the public and councillors were not informed about the incident, saying he would undertake a review of the council's reporting procedures by the end of the year.


Councillor Mike Lee wondered if there was something in the water causing a culture of secrecy, and councillor Cathy Casey said it was unbelievable that councillors were not told before, or during, a debate last week on switching to 1080 for pest control in the Hunua Ranges.

In an email to councillors and local board members, Mr Town said he was conscious of a new approach to pest management in the Hunua Ranges and was committed to carrying this out in an open and transparent manner.

The email contained a timeline of the incident, which showed council parks staff were told of the incident on May 15, but the council was not formally notified until June 11.

The Cosseys and Wairoa dams were closed on May 12 after traces of the herbicide applied to nearby forestry blocks were found in their water.

Tale of the taint
May 12: Herbicide sprayed over forestry blocks
May 14: 12mm rainfall in Cosseys and Wairoa dams
May 15: Positive results for herbicide recorded at dams
June 11: Watercare notifies council of contamination
June 23: Watercare and council staff review incident
July 21: No detectable levels of herbicide recorded in dams
Aug 25-Sept 25: Dams returned to service