The oil, which appears to be black oil, currently affects an area of shoreline of less than 50m and there is a light sheen on the water.
Residents of Matapihi are "irate" about continuing oil spills in Tauranga Harbour and the impact they are having on the environment, a regional councillor says.
"And I'm sure the rest of the residents in Tauranga Moana are as well," Matemoana McDonald, who represents the Mauao Māori Constituency, said yesterday.
McDonald said she had received a lot of complaints, mostly on social media, from members of the Matapihi community following the oil spill on Sunday.
Council staff collected 25 bags of oily organic debris from the shoreline at Matapihi following the spill.
McDonald said so far she had not been able to give residents a finite explanation as to the source of it and that did not help matters. It left things in limbo, she said.
A Bay of Plenty Regional Council spokeswoman said yesterday that there was no further update on the oil spill or its source and the investigation was ongoing.
A caller to the council's pollution prevention hotline reported it about 4pm on Sunday.
The spill, which appeared to be black oil, was south of the Matapihi rail bridge and covered an area of shoreline less than 50m in length.
Council workers cleaning up the oil spill from the shoreline at Matapihi on Sunday night. Photo / George Novak
A slight sheen was also visible on the water.
Council staff worked quickly on Sunday night with the hour and a half of light they had and returned the next morning to complete the job.
The council said on Monday that it had found no further spread of the oil.
McDonald said the spills were becoming more prevalent.
"It is a concern."
She said she had also had complaints this week from residents in other areas of Tauranga.
"People are alert to oil spills now and kind of kick in to that panic mode as soon as the notice comes out."
McDonald said it was important for councils to ensure that rules and regulations regarding oil spills were adhered to, to prevent spills happening.
"But I'm not fully convinced we're at that place yet."
McDonald urged the public to remain vigilant and urgently report any oil they see or smell in the harbour.
Regional councillor Matemoana McDonald, who represents the Mauao Māori Constituency. Photo / Supplied
Toi Ohomai Institute of Technology associate professor in resource management Dr Ian McLean congratulated the regional council for its prompt response to the spill.
"The thing about these small oil spills is that they never go away, there's always going to be another one. So the key is not to pretend that they're not going to exist, but to have a ready response team, properly resourced to get out there and deal with it."
Dr McLean said any oil in the harbour was a bad thing.
However, when he looked at photos of the clean-up effort, he also saw something else – an accumulation of wood and forest material on the beach, likely carried down rivers and into the harbour during recent storms.
"It's not forestry slash as in Tolaga Bay recently, it's just forest material, and it's accumulating in all the eddy points and smothering the beaches."
McLean said the bigger problem affecting the entire harbour was sedimentation runoff (including that forest material) and agrichemicals (polluting pesticides and herbicides) flowing into waterways.
"Our harbours are very sick and the primary problems are sedimentation and the hidden things, the things you can't see.
"You can't clear them up and yet they are doing serious damage on a much bigger scale than a small oil spill like this one."
Toi Ohomai Institute of Technology associate professor in resource management, Dr Ian McLean. Photo / File
McLean said while some of the washed-up forest material might come from native forests and is ultimately part of a natural process, a lot of it is not natural and is killing estuaries and wildlife.
"At least by having the oil on that stuff, it actually will have absorbed a lot of the oil, which makes it a lot easier for the council to pick it up, plus it means the council are actually cleaning up the beaches from other problems."
Emma-Leigh Hodge, Tauranga Green Party organiser, said she had been following the reports of the oil spill at Matapihi.
She commended the council staff on their "prompt and thorough response".
"I'll certainly be following news about how the oil came to be in the harbour with interest."
Reports can be made to the pollution hotline on 0800 884 883.
