A construction company fined $25,500 for stormwater contamination of the Clutha River at Wanaka has claimed the main cause of the alleged discharge was "systemic design issues''.
The Otago Regional Council took Northlake Investments Ltd and Civil Construction Ltd to court over the alleged discharge of silts and sediments on to land and into the river, between Lake Wanaka and Albert Town, from the nearby Northlake subdivision in 2017.
Civil Construction pleaded guilty to the charge and was convicted and fined in the Queenstown District Court yesterday.
Matthew Booth, the company's defence lawyer, alleged it was "Northlake, rather than CCL'' which was responsible for the stormwater system design, "then creating potential'' for discharge.
He said the amount of discharge was "fairly modest'' and although this was not a mitigating factor, it was also not an "aggravating'' factor.
The case before the Queenstown District Court related to discharges that allegedly took place on August 17 and 18.
ORC staff reported they found an overland flow of silt and sediment entering the river on August 17, causing a discolouration for more than 500m.
Further inspections the next day found the alleged discharge was continuing, but at a reduced flow.
Civil Construction reported measures were then taken to avoid any repetition, including increasing retention pond capacity, creating more drainage channels and removing built-up sediment.
ORC prosecutor Nathan Laws said Civil Construction's defence suggested the primary cause of the alleged discharge was "systemic'', but he argued the company's culpability was as the "implementer, not the designer of this system''.
"The defence seems to suggest it's the design of this system that led to the offence.''
Judge Brian Dwyer said the construction firm's offending was not deliberate, but refused its application for discharge without conviction, ordering it to pay the fine and additional court costs totalling almost $785.
He said it was a "substantial discharge'' that was caused in part by "substandard site management''.
Northlake entered a not guilty plea on August 8 last year and also appeared before the court yesterday.
The company's hearing was adjourned until April 29.
