A spill of about 400-600 litres of diesel into the South Dunedin stormwater network has prompted the council to appeal to the public to help them find the source.
The spill, which happened at Andersons Bay, has sparked a pollution response plan to mitigate its environmental impact, the council says.
Otago Regional Council manager of compliance Tami Sargeant said the spill was a serious breach.
“We’re looking at a significant amount of diesel that has been discharged into the stormwater network, and our investigations team are very keen to identify the source and determine what’s happened here.
“Given the volume of the diesel, we think it’s highly likely someone in the community will know how it got into the stormwater system," she said, adding that the adverse effects on the environment from such a spill can be "quite severe".
Sargeant said the pollution response team was using sorbent booms to stop the spread of diesel into Otago Harbour.
“The booms have been placed at the stormwater outfall into the Otago Harbour to soak up as much of the diesel contamination as possible and stop it from flowing further into the harbour.
“There remains an amount of diesel contamination in the stormwater network which will make its way to the harbour via the outfall pipe over the coming days.
“The time it takes for the diesel contamination to flush from the network depends on how much rain we get, but the booms will remain in place until the diesel has ceased discharging.”
Sargeant asked the public to pass along any information about the spill.
“We’d like to hear from anyone who may have seen or heard anything in the last 10-14 days that could potentially assist our investigation.”
People can get in touch anonymously with the investigations team via firstname.lastname@example.org or on 0800 800 033.