A scathing review of the committee charged with cleaning up Manukau's ailing harbour has forced Auckland Council to overhaul the "failing" forum.

Photo: RNZ / Jessie Chiang

The report, commissioned in 2018, found the Manukau Harbour Forum was "failing to achieve its vision" and would not do so without "significant change and additional resourcing".

Meanwhile, documents published by the council reveal the worsening state of the country's second-largest harbour.

Auckland Council's infrastructure and environmental services director Barry Potter on Friday said Manukau Harbour's overall ecological health grade had decreased from a D in 2016 to an E in 2018.

Overall, its water quality remained "poor", with nutrient readings "markedly above threshold levels" despite improvements at some sites.

The Manukau Harbour Forum was set up in 2010 in response to concern about the worsening condition of the waterway.

Its vision, which calls the harbour a "significant cultural, ecological, social and economic taonga", is a programme of "integrated harbour management" to make sure the waterway has a "rich and diverse marine and terrestrial environment that is able to be enjoyed by all".

But Dr Nigel Bradly's report uncovered a number of reasons why the forum was failing to deliver, including inadequate resourcing, a lack of understanding of the harbour's health and the absence of long-term planning.

Bradly made a raft of recommendations, such as hiring a paid project manager, completing a report to understand the state of the harbour and creating a long-term plan.

Potter said some recommendations had been completed following the report's release, while others were underway or yet to begin.

Recruitment of a project manager had commenced, as had steps to include two Auckland councillors on the forum.

Other recommendations, including a state of the harbour report, would take longer to complete.

Potter said the forum, made up of local board members, was created with a vision to "implement strategies that will improve the environmental quality of the harbour".

Health grades within Manukau Harbour varied greatly, he said.

Some sites in the wider harbour ranked as "extremely good" and "moderate", while others, such as Māngere Inlet and Pahurehure, were deemed "unhealthy".

On Friday, Mayor Phil Goff, who has consistently trumpeted Auckland Council's water quality improvements under his mayoralty, said a number of the Bradly report's recommendations required more "work and options analysis", which staff would complete over the coming months.

Under Goff, Auckland Council introduced a targeted rate to clean up the region's beaches.

In November 2018, the mayor said he was "really quite proud" about the "ongoing improvement in water quality".

"It was really good to see four beaches on the Manukau Harbour, that have been closed for upwards of 20 years, reopened to the public because we've got better ways of measuring pollution and we've been dealing with the causes of the pollution," he said at the time, pointing to Armour Bay, Taumanu East, Clarks Beach and Weymouth Beach.

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