A video circulating on social media showing raw sewage flowing from the Shannon Wastewater Treatment Plant into a nearby stream is a complete distortion of the facts, says Horowhenua District Council.

But the person who shot the video says it speaks for itself and he's not changing his stance on the issue.

The video commentary states there is raw effluent including toilet paper along with brown-coloured water flowing from Otauru Stream and then piped into the Mangaore Stream, which feeds the Manawatu River.

Council says there is no way toilet paper could get through the 40-plus days in a treatment holding pond to then be pumped into the stream.


The water is a dark colour because of algae, council says.

Council currently has resource consent to pump 3000 cubic metres of treated sewage into the stream daily until the new wastewater treatment system costing more than $3m is completed which will see 80 per cent of the treated wastewater spread onto farm paddocks in the future. That is also an issue for local iwi who say the land chosen is not suitable.

Councillor Ross Campbell said on Friday evening he received a number of calls from residents concerned at what they saw flowing into the stream where children were swimming.

He said he went down and saw fresh "raw sewage" being pumped straight into the stream.

"It was disgusting. ... it was straight from the inlet to the pump. They were sluicing the muck out. ... [the community] were promised absolutely nothing would go into the water."

Mr Campbell said he asked a Downers employee to turn off the pump as it was illegal and in breach of the resource consent.

Returning the next day he said the pump was working again with raw sewage and toilet paper again pouring from the pipe.

"The pond had decreased in depth by about 25 per cent ... I looked at the pumps and there was pitch black water coming through. My word it was coming straight into the stream. The sewage was emptying straight out as it was coming in."

Contacting the Horizons Regional Council hotline an inspector was sent out who stated the council was working within the consent, said Mr Campbell.

He said he saw it with his own eyes and the illegal practise needed to stop, he said.

"It's a joke really. This is absolutely shocking ... the stench was horrible. This was straight sewage, no treatment, no nothing. It's putting everyone at risk who uses the stream."

Horowhenua District Council chief executive David Clapperton said the "facts had been distorted".

"We realise this video does look disturbing, but the footage and commentary claiming that raw sewage is entering the Mangaore Stream, with fresh toilet paper floating on top, is a complete distortion of facts."

"This video does not make sense and exists to create misguidance. It appears that the toilet paper seen in the video is a result of third-party action that neither council nor its contractors are aware of or have any control over."

Shannon's wastewater enters the plant and then goes through a series of treatments and screening for 40 days before it is pumped into the stream.

"So, how can fresh toilet paper end up in the stream after floating for over 40 days in a pond covering 2.6 hectares, travelling through a fine mechanical screen, and with an aerator, baffles, and constructed wetland?" Mr Clapperton said.

Horizons is investigating to ensure council is meeting conditions of the consent granted.

Meanwhile, Mr Clapperton said had the $3m project been allowed to proceed without protests and other interferences by some misinformed individuals and groups, council could have already stopped 100 per cent discharge to the stream.

"This can only be achieved if the council is supported in its genuine endeavours. The more bottlenecks that are put in the way to undermine and obstruct the progress of this project, the less likely that the desired outcomes to clean-up the river can be achieved."

Council's group manager Infrastructure Services, Gallo Saidy said discolouration of the water shown in the video was natural occurring algae.

"Wastewater treatment processes require a range of natural organisms to work effectively. Some organisms do not survive in untreated wastewater, whereas others are needed to actually provide the treatment," he said.

Algae are simple organisms that can range in colour from blue-green, green, brown and red. They are often found in wastewater treatment ponds.

"The presence of algae does not indicate the presence of raw sewage, and in fact green algae indicates a healthy treatment pond that is working as expected. This is primarily as algae introduce oxygen through photosynthesis to help treat wastewater. An increase in the dissolved oxygen levels in the treated effluent discharge is important for water life."

Meanwhile, councillor Michael Feyen backs Mr Campbell's claims and says council's take on the issue was misleading and full of half-truths.

"HDC is a top drawer polluter. This is not the first time accurate film footage has been taken of wilful contamination of the Manawatu River ... I took extensive film footage 14 months ago and was ridiculed at the time. The whole manner in which this issue has been handled is a disgrace and lacks integrity in many forms."