Christchurch Mayor Phil Mauger’s proposal to divert partially treated wastewater to the ocean as a way to ease the city’s worsening treatment plant stench is still far from being ready for approval.

Environment Canterbury Chair Deon Swiggs said the concept remained at an early stage.

“A detailed plan has not yet been developed by City Council staff,” he said.

“As expected, there is considerable work required to develop the concept into something that can be assessed and implemented.”

The proposal involves diverting tens of millions of litres of partially treated and chlorinated wastewater through Christchurch’s existing ocean outfall pipe each day as a temporary measure to reduce pressure on the Bromley wastewater treatment plant and help ease the smell affecting large parts of the city.

Environment Canterbury staff met with Christchurch City Council on Wednesday to discuss the idea, but Swiggs said more work was needed before it could be properly evaluated.

“We will continue to work closely with and support Christchurch City Council, in partnership with mana whenua, to ensure they prepare a fully developed proposal that is satisfactory to all parties and the meets requirements for a resource consent.”

Environment Canterbury issued an abatement notice after widespread complaints about the smell from the Bromley facility.

Swiggs said the regional council recognised the impact the odour was having on residents.

“We know many areas across Christchurch are currently being affected by unpleasant smells coming from the Christchurch Wastewater Treatment Plant in Bromley,” he said.

“As the environmental regulator, it’s our responsibility to ensure impacts like this are understood and addressed, and we acknowledge the real strain the stench is placing on people’s daily lives.”

Christchurch City Council has until 16 March to provide Environment Canterbury with a plan outlining both short and long term odour mitigation measures, along with achievable timeframes.

Swiggs said Environment Canterbury would continue working with the council and the National Public Health Service as efforts continue to resolve the issue for affected communities.