'Raw sewage' left to flow across farmland and into Kaipara Harbour

Grant McCallum's photo showing raw sewage overflowing. Photo / Supplied

A Kaipara Harbour farmer says raw sewage was left to flow into local waterways for up to two weeks.

Grant McCallum, speaking with Jamie Mackay on Newstalk ZB programme The Country, said the overflowing sewage was discovered by a Wellsford farmer who leases the land.

McCallum said Auckland Council sent up one-tonne diggers to deal with the broken and blocked pipes but the machines were too small.

Listen to Jamie Mackay's interview with Grant McCallum below:

Five days later the sewage was still flowing, so the farmer contacted Rodney Local Board member Colin Smith to ask him to get involved.

Smith said there had been problems with the sewerage infrastructure in the area before.

"The sewerage line in the area's been broken for a long time...it's buggered."

He said it took far too long for the problem to be fixed.

"The thing is it could've been done in eight hours and it took weeks."

A broken wastewater pipe that caused raw sewage to flow onto farmland. Photo / Supplied

Eventually a 30-tonne digger was brought in to solve the problem.

McCallum said it took about two weeks for Auckland Council to stop the overflowing sewage.

He described the process as a "comedy of errors".

He said it wasn't the first time this had happened and the local sewerage infrastructure was "past it".

McCallum said he wanted to know if anyone would be held criminally liable.

"How do councils get away with it when farmers don't?"

A spokeswoman for Auckland Council's Watercare has apologised for the way the sewage overflow was handled.

"We agree with the farmer that this wastewater overflow was handled poorly and would like to apologise to him for the impact it had on his farm.

"We are extremely disappointed with our contractor Downer who did not meet our performance expectations on this occasion.

"We can assure the farmer that the incident has prompted an internal review to reduce the likelihood of it happening again."