A minor pollution spill on the Frankton Track went undetected last week after contractors mistook the cause as a blocked stormwater manhole and rotting tree matter.
Queenstown Lakes District Council infrastructure services general manager Mark Kunath said when the contractors first investigated a report of odour on January 18, they found a blocked stormwater manhole, which was cleared.
However, several days later two further calls were received from the public and contractors returned to locate a minor spill on Friday.
The cause was a blocked wastewater manhole which had earlier leaked into the stormwater system.
