Jessie McVeagh, of the environmental group Te Mauri o Te Wai, said the aim was to draw national attention to the state of the harbour.
"Our harbour is being polluted from lots of sources, but also from human waste. We've come to Waitangi because it is a Treaty issue – under Article 2 all the treasures, the taonga, were to be honoured. Water is one of those things and getting kai moana without the offence of human waste is another."
McVeagh said she was also petitioning central government to provide more financial support to small communities that couldn't afford proper wastewater systems on their own.
Dallas Williams, who represents the hapū of Omanaia, said effluent in the harbour – even if it had been treated – was not okay or culturally acceptable.
Sewage was not the only cause of pollution but it was the current focus for the practical reason that a number of resource consents, starting with the Opononi-Omapere wastewater plant, were coming up for renewal soon.
The Far North District Council says it's not correct to say it's doing nothing about the sewage issues, and plenty of work is being carried out on the four treatment plants discharging into the harbour.