Ngāi Te Rangi chief executive Paora Stanley told the Herald the threatened blockade is a response to frustration over his six months of unsuccessful meetings with the port this year, trying to get agreement for a long-term project to monitor and remediate the harbour.
Stanley said the trust is administered by the port, hard to navigate and that "the harbour's going to take a lot more than $990,000 I can assure you". He understood the trust's main function was to provide scholarships.
"If we could access that $990,000 for remedial work the application would be there on Monday."
The iwi's aim of a 35-year monitoring and remediation project would need at least $7m, and Ngāi Te Rangi would vote on Wednesday to kicking it off with $1.1m of its own money, he said.
The port wasn't being asked for money, just agreement to the project. Together the parties could apply for Government funding, Stanley said.
Nor did the iwi want the port closed or its work restricted.
"The real issue for us is the environment. The Māori economy in Tauranga is about $2 billion - about half of that is tied up in horticulture. We have a vested interest in getting our products overseas. But we are not going to sacrifice the environment for money."
The Port of Tauranga is the country's biggest and its main export gateway.
Port chief executive Leonard Sampson said the port had "no debate" with the iwi over the need to monitor and care for the harbour. It had paid for monitoring before and "we are committed to working with iwi".
"If that was all that's being asked for, we are 100 per cent in agreement. We want the same outcome for the harbour."
Stanley said plans for on-water action were "advanced". The port, police and harbourmaster had been told they would get 48 hours' notice of the blockade, which was to draw attention to concern about "the level of degradation" of the harbour and outlying shellfish beds since the port's last dredging.
"It (giving notice) destroys our surprise but more importantly, it sustains the safety issue. The port will work around with 48 hours notice.
"But if that doesn't work, it will get to the stage we won't notify them."
The port contends "numerous" ecological and hydrodynamic marine studies have been undertaken since dredging for a major capital project in 2015. They had deemed "insignificant" the environmental impacts on the harbour and surrounding marine environments. But Stanley said snapshots shortly after 2015 don't show longer-term effects or how widely the impacts spread.
He said concern about the degradation is "not just Māori". Many non-Māori harbour users would be seen at the protest.
The port has applied for resource consent for a 385m container wharf extension and 1.5m cubic metres of associated dredging. This compares to 15m cubic metres consented under a capital dredging project in 2013 for channel deepening to provide entry for bigger container and log ships. Around 6m cubic metres of this consent was undertaken in 2015.
Stanley said the comparison was "a play on words".
The extension has been planned since 2018. The port has signalled it will run out of capacity by 2025 without it as freight volumes balloon. A hearing of the application was due to start in the Environment Court last week but was adjourned until an unknown date, likely next year, due to Covid-19 infections among some submitters. The project is now running $20m over its $68.5m budget. It was declined for the Government's shovel-ready and Covid-19 fast-track infrastructure project programmes in 2020 and 2021 respectively.
Stanley questioned why the dredging can not be done in stages instead of creating "a bloody big hole". That way monitoring and if necessary remediation could be carried out after each stage.
The port's Sampson said a single dredging operation would have less impact.
