The Wellington City councillor who mooted dumping one million litres of sludge a day into the Cook Strait to cut costs now says it's not an option he can support.

The proposal went down like a cup of cold sick with the majority of city councillors, while Forest & Bird and the surfing community has labelled it a "step backwards".

Trucks are doing the work of a pipe that broke in January by transferring sludge between Moa Point treatment plant and the landfill at Carey's Gully until the pipeline can be repaired.

This operation costs a whopping $680,000 per week, or almost $3 million per month.


Three Waters portfolio leader councillor Sean Rush proposed dumping the sludge into the Cook Strait using a pipeline which currently discharges treated water.

His suggestion came as the city council faces a $70m fiscal shortfall for the 2020/21 year with its revenue streams drying up in Covid-19.

Rush told the Herald some of the preliminary advice he based the suggestion off had since been corrected.

He said it was now clear the emergency provision in the resource consent would unlikely be met, a repair was more imminent than first thought, and beaches would have to close due to potential public health issues.

"The context and the consequences have changed considerably.... at this point in time there's certainly no case to be made for using the outfall."

Rush stood by his decision to raise the question about the cost of the trucking operation.

Greater Wellington Regional Council environment general manager Alistair Cross said the current consent only allowed the disposal of sludge in the Cook Strait for genuine emergency works.

"It's likely that a discharge into the strait would require a new resource consent and require a public notification period and is therefore not a short process."


Cross said the regional council, as the environmental regulator, was working closely with the city council and Wellington Water to resolve the issue.

Wellington City councillor Sean Rush suggested dumping sludge in the Cook Strait to cut costs. Photo / Mark Mitchell
Wellington City councillor Sean Rush suggested dumping sludge in the Cook Strait to cut costs. Photo / Mark Mitchell

A publicly notified consent application has to be open for submissions for 20 working days and can go to a hearing if people want to present their arguments in person.

In that case, the hearing panel would make a decision on the application within an additional 15 working days.

Furthermore, a recent update from Wellington Water on the pipe repair suggested a fix would likely be in place before a new resource consent could be secured.

Special permission has been granted for six international experts to travel to New Zealand and are expected to arrive in the middle of this month.

They will then self-isolate for 14 days before installing liners manufactured in Germany, meaning the repair could be completed as early as mid-May.

Moa Point treatment plant started operating in 1998. Photo / Mark Mitchell
Moa Point treatment plant started operating in 1998. Photo / Mark Mitchell

Forest & Bird conservation spokesman Tom Kay said he would be concerned for wildlife like whales and a hoki fishery in the Cook Strait if the move went ahead.

He said it would be a step backwards.

"We've got a lot of councils around the country working really hard to reduce the impact of their wastewater discharges on streams, rivers and the coast.

"Now is not the time to roll back on all the environmental progress we've made as a city and as a country over the past few decades."

Moa Point treatment plant began operating in 1998.

Prior to the sludge pipeline, wastewater was discharged via a shoreline outfall at Tarakena Bay. The effluent was screened but not treated.

Wellington Boardriders Club founding member James Whitaker said dumping sludge in the Cook Strait would be a "huge failure" on the council's behalf.

"Every couple of minutes there's a truck going past with a whole lot of sludge in it, and that kind of ruins the ambience down there on the waterfront, but we'd much rather know that sludge is going to the landfill instead of going directly into the sea, which would be disgusting."

Whitaker said the water around Lyall Bay and surrounding areas has improved dramatically over recent years and become a pleasant place the city is proud of.

"Dumping the sludge in the Cook Strait would be a huge setback."

Moa Point Rd resident Andrea Cootes previously told the Herald the smell from the sludge trucking operation was revolting.

"It smells like someone's done a poo. I cried and thought if this is how it's going to be, I'll go and stay somewhere else, it's been that bad."

But she said she would also rather put up with the stench than see the sludge poured into the ocean. The Government's official Covid-19 advisory website