Christchurch’s long running wastewater crisis has sparked a sharp exchange between two local MPs over a controversial proposal aimed at easing the city’s ongoing stench problem.

During a discussion on the issue with chrislynchmedia.com, Banks Peninsula MP Tracey McLellan and Ilam MP Hamish Campbell clashed over Christchurch Mayor Phil Mauger’s idea to discharge partially treated wastewater into the ocean as a temporary measure.

The proposal would see a portion of treated wastewater bypass some of the settling ponds at the Christchurch Wastewater Treatment Plant before being discharged through the existing ocean outfall pipe.

McLellan said she was not prepared to support the proposal until expert advice confirmed it was safe.

“I don’t know enough about this particular issue,” McLellan said. “I saw the media during the week and I thought gosh my first instinct was this doesn’t sound quite right.”

She said while residents should not have to continue living with the smell, any solution must be based on evidence.

“The people of the east actually the people all over Christchurch shouldn’t be having to put up with this stench years and years later,” she said. “But we have to be really really careful that we don’t create another problem trying to solve this problem.”

McLellan said she would wait for expert advice before deciding whether to support the proposal. “I will just like everybody else be waiting with baited breath to see what the actual experts say about this issue,” she said. “It may be a fantastic idea we don’t know yet so let’s just hold on.”

Campbell backed the mayor’s proposal and accused some MPs of opposing action. “I think it’s very well and good for some of the local Labour MPs to be against doing anything,” Campbell said. “I think this is a method that actually will help people out in the east.

“It’s about bypassing some of the ponds,” he said. “It means the stuff going through the pipe will actually have gone through the treatment plant.”

He said additional chlorine would also be used before the water was discharged offshore. “There will be some extra chlorine added to make sure there’s no bugs that then get released,” Campbell said.

“The majority of the wastewater going through the plant will still go to the settling ponds,” he said. “This is only a small percentage that will then get shipped out to sea which is about three kilometres.”

McLellan rejected the suggestion she opposed action on the issue. “That’s quite an outrageous comment,” she said. “We’re the ones that are living here. My office is right in the middle of where the smell happens all the time. I smell it every day.”

“I’ll support anything that has good evidence behind it,” McLellan said. “When the officials come back and the experts say that this is a good idea we’ll be the first people to support it. But until that happens I’m not interested in creating another problem by solving one other.”

Campbell said construction of the long term solution at the wastewater treatment plant was already underway. “There are diggers on the ground already to make sure that this happens,” he said. “Anything to help the construction of the activated sludge reactor should be encouraged.”

The new facility is expected to take up to two years to complete.