Gas levels at fire-damaged Christchurch sewage treatment plant worse in area not covered by council payment

The rotten smell from the fire-damaged Christchurch sewage treatment plant could start to dissipate in just two months as council staff plan to pay out grants to affected residents further afield.

Christchurch City Council’s Bromley factory was ravaged by a devastating fire in November 2021, creating a stench that has plagued residents for months.

Christchurch City Council has unveiled new data on hydrogen sulphide levels at three continuous air monitoring sites – one at Bromley School, one on Marine Pde northeast of the ponds and one on Rudds Rd in west of the ponds.

Council staff also held a virtual meeting on Wednesday evening to update the community on their progress at the treatment plant and gave residents the opportunity to ask questions about the lingering smell.

READ MORE:
* Christchurch’s treated wastewater quality deteriorates as winter bites
* Sulphurous gases detected at damaged Christchurch sewage treatment plant
* ‘Horrible, foul and toxic smell’ from Christchurch sewage treatment plant worsens

Hydrogen sulfide – one of the gases causing the stench – can be smelled by most people at just 0.03 parts per million (ppm) and could start to cause health effects like headaches and nausea.

The data showed that in the three weeks from June 17 to July 7, hydrogen sulphide levels never exceeded 0.03ppm at the Bromley School test site.

Marine Parade residents Simon Bartholomew and Jane Horne.

JOHN KIRK-ANDERSON/Stuff

Marine Parade residents Simon Bartholomew and Jane Horne.

The same couldn’t be said for Rudds Rd in the nearby town of Linwood, where levels exceeded 0.03ppm for at least seven days during the same period, peaking at just under 0.05ppm.

But the highest levels were at the Marine Pde test site, which is outside the limits to receive the council’s $200 payment for affected households.

Marine Pde had hydrogen sulfide levels above 0.03ppm for at least nine days since June 17, with levels peaking at nearly 0.11ppm on July 4 – more than three times the ‘threshold of concern’ of the council.

The council said the spike was caused by “a moderate south-westerly wind which blew persistently in that direction during the day”.

Simon Bartholomew and Jane Horne, who live on Marine Pde, said most of their neighbors have become accustomed to the smell.

Bartholomew said he sometimes woke up at 3 or 4 a.m. when the stench was “shocking”.

Horne said it was definitely a “poo smell — along with something else.”

Hydrogen sulphide levels over the past three weeks at Christchurch City Council's Marine Parade monitoring site.

Christchurch City Council / Supplied

Hydrogen sulphide levels over the past three weeks at Christchurch City Council’s Marine Parade monitoring site.

“I’m quite safe now, [but] there are definitely days when it’s much worse,” she said.

“Some days here are really bad – you don’t want to put your laundry out.”

Horne helped an elderly neighbor with reduced mobility on nearby Estuary Rd, who was forced to tolerate pong all the time.

“She can’t take it…She says she has headaches because of it, she can’t go out.”

She and other vulnerable members of the community couldn’t easily get to meetings, Horne said, and often didn’t have access to the internet to get updates on the situation.

“She’s incredibly frustrated, she feels completely forgotten.”

Residents living inside this area will be eligible for financial assistance from Christchurch City Council to help them deal with the stench from the sewage treatment plant.

Google Maps/provided

Residents living inside this area will be eligible for financial assistance from Christchurch City Council to help them deal with the stench from the sewage treatment plant.

Bartholomew thought the ideal solution was to expand the area for those entitled to compensation and get rid of the $200 payment – ​​instead paying different amounts based on need.

“We are not too affected apart from the smell, [so] we prefer the money to go to people who are…even if it’s mental health.

Horne said paying compensation in increments over time could also help.

“[If you get] $200 now to do your laundry and wash your curtains, next month it will be the same.

KAI SCHWOERER/STUFF

Damaged by fire in November 2021, the Christchurch sewage treatment plant in Bromley has since been producing a stench that has plagued nearby residents.

At the community meeting, Christchurch City Council chief infrastructure officer Jane Davis acknowledged living near the factory since the fire “has been quite an appalling experience”, but the end was in sight.

“We’re almost there in terms of getting rid of the really nasty smell.”

While the council found hydrogen sulfide at high levels, health advisers argued it was highly unlikely to cause any long-term health effects, she said.

“Although there are certainly people who are suffering… [Health NZ are] not seeing major health problems in the community.

They encouraged anyone with health problems to see their doctor.

Most of the smell now came from the oxidation pools rather than the fire-damaged bacteria filters.

Progress in cleaning fire-damaged trickle filters at Christchurch City Council's Bromley Wastewater Treatment Plant from 13 July.

Christchurch City Council / Supplied

Progress in cleaning fire-damaged trickle filters at Christchurch City Council’s Bromley Wastewater Treatment Plant from 13 July.

Three Waters manager Helen Beaumont said the loss of the bacteria filters had been “catastrophic”.

But many infrastructure works had now been completed and would improve the quality of the sewage before it was discharged into the ponds, eventually eliminating the smell of hydrogen sulphide.

Over the next eight weeks, the poor quality water would be flushed out and the smell should improve, Beaumont said.

Community Partnerships Manager Gary Watson said about 66% of eligible households applied for the $200 grant and were accepted.

The board had also paid out 215 out-of-area grants.

Given the results of the air sampling, staff were investigating the possibility of expanding the area eligible for grants, he said, which could include New Brighton and South Brighton.

The Department of Education has also provided air purifiers to all local schools, and the council will provide grants to seven schools and 19 early learning centres.

Check Also

Reusable polymer can remove dyes from wastewater

Researchers from North Carolina State University have demonstrated that a synthetic polymer can remove certain …