Almost 60 oil spills have seen almost 3000 litres of oil spilt into Tauranga Harbour since 2008 - not including oil from the wrecked Rena or the recent Mobil pipe leak - a figure described by an iwi leader as gobsmacking.
There have been 57 spills dealt with by Bay of Plenty Regional Council or Maritime New Zealand in this time frame, three of which have been prosecuted and one under investigation.
Te Runanga o Ngai Te Rangi manager of the resource management unit, Reon Tuanau, said the number of spills was "gobsmacking".
Mr Tuanau said Ngai Te Rangi was involved in monitoring the harbour and helped clean up larger spills.
"It's a major concern for us. We're slowly trying to push the regional council and the companies to do better with their work sites. The Port of Tauranga has made significant changes to the way they operate.
"I think we've made progress."
Bay of Plenty Regional Council marine pollution prevention officer Adrian Heays said costs were recovered from serious spillers Liloa and Mobil, and other identified spillers.
Mr Heays said when a major spill occurred from a vessel, a marine oil transfer site or an offshore facility, costs were recovered from a fund made up by levies from the oil industry.
This fund was also used when all reasonable efforts to recover costs from a major spiller were unsuccessful or no spiller was identified. For the smaller spills where no spiller was identified, the council bore the cost.
Mr Heays said when a spiller was identified, enforcement action was taken on a case-by-case basis.
"Because of the traffic within Tauranga Harbour, Maritime New Zealand rates the risk of an oil spill in this area as high. Because of previous events we have a high awareness among key stakeholders such as iwi, the port company, contractors, marine industrial sites such as marinas and the public in general."
Senior environmental scientist of marine ecology Stephen Park said the council had monitoring programmes in place within Tauranga Harbour that showed the wider harbour was in a reasonably healthy condition. This monitoring showed the level of oil contaminants within Tauranga Harbour was generally well below the levels at which marine life might be adversely affected.
Transport Minister and Tauranga MP Simon Bridges said 57 spills was a large number but many of those were small spills and often non-commercial.
"Given our status in the Bay of Plenty as a port and as a place where people love their harbour and see it as part of their birth right, I expect to some extent to see these things happening.
"That said, we want to minimise them as best we can."
Mr Bridges said he had taken a lot of feedback since becoming MP in 2008 about spills.
"And, like other locals, I lived through the Rena and remember the first days it happened, going down to the beach and getting the oil on my shoes."
Mr Bridges said he was working on a review of the country's oil response, which included a proposal to increase the "levels of capability to deal with oil spills".
He encouraged locals to take part in the consultation for the Review of Oil Pollution Levy 2015/2016, which Maritime New Zealand was running. The options being consulted on included more booms, dispersants, and other equipment and vessels for prompt response.
New Zealand First MP Clayton Mitchell said he had requested copies of a report on the Mobil spill from the regional council.
Mr Mitchell said oil flow metres were not mentioned at all in the report he had been given, and he believed they should be so in the case of a spill, it was obvious how much had spilled.
Mr Mitchell's opinion was the harbour was "completely under resourced" for future oil spills and the right equipment was not on standby.
Chrissy Jefferson from Oropi Native Bird Care Trust said any form of oil spill was a concern not only for the environmental issues but for the bird life.
Mrs Jefferson has helped oiled wildlife after the Rena and Mobil incidents and said she had not had any birds brought to her from other spills.