Hamilton City Council offices. File photo. Photo: Hamilton City Council
The Hamilton City Council has been fined $76,500 for discharging over a million litres of wastewater, including sewage, into a stream.
The contamination of a tributary of the Te Awa O Katapaki Stream in Flagstaff carried on for nine days in October 2020.
The council estimated that 1.27 million litres of wastewater was discharged into the stream over the nine-day period -approximately half the volume of an Olympic size swimming pool.
The point of discharge was less than 2km from the Waikato River.
Hamilton City Council regional compliance manager Patrick Lynch said it was an "unfortunate case".
"Hamilton City Council maintains a very large wastewater network for the more than 160,000 residents and numerous businesses of Hamilton.
"By and large, they do that very well from a regulatory and environmental perspective. However, in this instance, they have dropped the ball, resulting in avoidable discharges of large volumes of contaminant into a tributary of the Te Awa O Katapaki Stream in Flagstaff."
The Hamilton District Court heard that council staff knew about the contamination for several days before the discharge was stopped.
"Our investigation revealed that staff within Hamilton City Council were aware of the contaminated stream on 6 October 2020. They also knew it was likely the contamination had been occurring for some time," Lynch said.
The council blamed a series of communication failures for earlier action not being taken.
"Despite having that knowledge, through a series of communication failures within the city council, the discharge was not stopped until 12 October."
"This is a very clear reminder to any company, or council, that manages large volumes of contaminant as part of their business. They must have fit for purpose infrastructure, manage that infrastructure well and ensure they take immediate steps to mitigate any discharges that occur into the environment," Lynch said.
The source of the contamination was found to have been an overflow from the wastewater system into the stormwater system, which then discharged into the stream, he said.
A review of council data found loss of wastewater into the environment had occurred as early as 4 October.
