Four councils are looking to formalise their relationship in preparation for Treaty negotiations between the Crown and Ngati Whatua which will have a strong impact on the Kaipara Harbour.

The Kaipara Harbour and its catchments are currently part of a Ngati Whatua Treaty settlement. While most of the iwi's historical claims have been settled, the remaining claims and redress over Kaipara Moana are yet to be finalised.

The Kaipara Harbour currently makes up about a third of Northland's total land mass and is one of the largest harbours in the world. It covers 947 square kilometres at high tide, with 409 square kilometres exposed as mudflats and sandflats at low tide. Northland Regional Council, Auckland Council, Kaipara District Council and Whangarei District Council - who all share regulatory responsibility over the harbour and its catchment - have established a draft Memorandum of Understanding (MOU) between them to prepare for any development in negotiations between Ngati Whatua and the Crown.

"We've worked together on the harbour for over three years and this is about being prepared for settlement, said Northland regional councillor Graeme Ramsey.


"It's good governance, we know we have to pay more attention to the harbour and working with Ngati Whatua is a key part of that."

At this stage Ngati Whatua have signed a framework agreement with the Crown which outlines key elements to be negotiated.

The framework documents the intention for the development of a co-governance body consisting of the four relevant councils, hapu and iwi.

Mr Ramsey said Ngati Whatua and the four councils had been working towards improving the health of the Kaipara Harbour through the Integrated Kaipara Harbour Management Group.

A Treaty settlement would strengthen the work they are doing, he said.

"Sedimentation is a big problem, all you have to do is take a look at some parts of the harbour. There are new aquatic pests ... The health of the Kaipara Harbour is not good."

The MOU has not yet been signed by the council but Mr Ramsey said it was likely the Northland Regional Council would sign it. The MOU would include establishing a Kaipara Moana Negotiations Working Party comprising at least one elected representative from each council.