Frequent users of an Auckland creek say they could still be swimming with floating faeces and untreated raw sewage if it wasn't for a local kayaker who discovered a major rupture of a wastewater pipe.

Russell Cavanagh lives on the Te Atatu Peninsula and regularly uses Henderson Creek.

He discovered the leak late last month and said it was disgusting.

"It smelt just...purely like an open sewer," he said.

"I could see floating turds, I could see floating sanitary napkins, I could see fish eating the turds - even some birds were eating the turds.

"There's no nice way of putting it, it was just straight up raw sewage."

There is no raw sewage leaking into the river now, but it has left a mark.

Dozens of sanitary pads are still stuck onto the banks, turned muddy and brown.

Mr Cavanagh reported the leak to Watercare the day after he found it.

But he has no idea how long the pipe had been broken.

"I just have to stick to the facts, I could see the raw sewage pouring into the creek on the 25th [of October]," he said.

"Earlier, I had gone kayaking and come out of the water with a brown stain on the kayak and seen brown trails of whatever that smelt like sewage on the water.

"But I really didn't know if it was a sediment or if it was a one-off event."

Photo: RNZ / Supplied

Chris Ballantyne, who has lived on the Te Atatu Peninsula for the past 20 years, says if it was not for Mr Cavanagh, hundreds of people would have still been using the creek.

"You could come down to the Taipari Strand (section of the Henderson Creek) here any weekend and see dogs in the water, people waterskiing, kayaks, people sailing, kids swimming - the river is alive," he said.

"Everyone was completely unaware of what was a major pipe rupture and for us that's the major breakdown."

In a statement, Watercare said it was able to channel most of the wastewater flow into another pipe.

But it recently discovered more sewage being discharged into the creek.

Photo: RNZ / Supplied

Watercare said that was repaired last Saturday.

It apologised to users of the creek.

Mr Ballantyne said the community wanted to work with Watercare to keep the waterways clean, but the organisation had to be more upfront.

"Sometimes I fear there's some PR spin that comes out and we just want to understand what the situation is," he said.

"We understand there's been decades of under-investment in infrastructure, we've got a growing population."

"But we want to know what's happening, what the plan is, when it's going to be delivered, whether there's a risk to our community and what we can do as a community to help."

The warning signs at the creek say people should stay out of the water until the end of December, or until the signs are removed.

Mr Ballantyne said locals were forming a River Care group to try and tackle the sewage overflow problem.