Christchurch Wastewater Treatment Plant update

Thursday 5 February 

The latest

The team will work all through the long weekend to keep the plant running effectively and keep any odour to a minimum. Today, we can report that the health of the ponds is still showing signs of improvement – we're reviewing the preliminary algae report, dosing the ponds with hydrogen peroxide, and fast-tracking the installation of a new aerator for Pond 2B for early next week. We'll keep a close eye on the weather, and how much odour is being generated, as we get it up and running.

In the background, we're also working to get our community odour monitoring dashboard online. We're also seeing improvement in the level of hydrogen sulphide.

Odour mitigation plan

We've just approved our step-by-step plan to mitigate the odour and you can read it here.

Communication over Waitangi weekend

With decent weather in the forecast for the long weekend, we're cautiously optimistic the situation at the plant will continue to improve. You'll hear from us on Saturday afternoon with a regular update, unless there's a sudden change of status at the plant, in which case we'll be in touch as soon as we can.

Sludge reactor progress

We've confirmed the timeline for construction of the new activated sludge reactor – the earthworks have already started. Once it's up and running, the new reactor will fix the odour issues. You can see our plans on the timeline at the bottom of this page.

Latest hydrogen sulphide monitoring 

We’ve increased hydrogen sulphide monitoring to twice weekly. See the latest result below.

The biological health of the ponds is fragile. Significant spikes of odour are being detected at community monitoring sites. Our teams are doing everything they can to address the current situation.

An update to our odour status map

You can always see the latest status, including when it was last updated, on our website. 

Health, wellbeing and support services 

We’re sorry for the impact this continues to have on you and your whānau. Please be assured we are doing everything we can to support the system’s recovery and reduce odour where possible.

Here's the latest advice from Dr Imogen Evans, Public Health Medical Specialist for the National Public Health Service:

"Exposure to hydrogen sulphide stench arising from the Christchurch Wastewater Treatment Plant can cause nausea, headaches, eye and throat irritation, skin irritation, sleep disturbance, and worsening asthma symptoms at relatively low concentrations. 
 
"If people exposed to the stench don't experience physical health effects, continued exposure to unpleasant or nasty, noxious stench can still have an adverse effect on people's mental wellbeing. 
 
"While exposure to hydrogen sulphide is unpleasant and may result in health effects, it doesn’t accumulate in the body. Any health effects would be expected to resolve when the odours are brought back to normal levels, and long-term health effects are highly unlikely. 
 
"People experiencing health issues as a result of the stench coming from the treatment plant should seek health advice from their GP, doctor, Hauora or healthcare provider, or call Healthline free on 0800 611 116, anytime 24/7 for advice as soon as possible. In an emergency call 111."

There are also free services across Ōtautahi Christchurch available to support and enhance overall health and wellbeing. These include:

Health Improvement Practitioners (HIPs)

HIPs are qualified mental health professionals based in General Practices (GPs). They offer free, 15–30 minute sessions focused on practical strategies to support mental and physical wellbeing. There is no limit to the number of sessions you can access.

You can book directly through your GP.

Pae Ora ki Waitaha Support

Pae Ora ki Waitaha is a free healthy lifestyles service developed with Māori and Pasifika providers.

More information is available on their website. 

Healthline

Healthline is a free over-the-phone health service available 24 hours a day, seven days a week. If you or someone in your family is unwell, you can call Healthline and speak to experienced nurses and paramedics for health advice and information about what to do next.  

Call 0800 611 116.

Stay updated

We want everyone to be able to stay updated on what's happening at the Christchurch Wastewater Treatment Plant, and we regularly post new information on ccc.govt.nz/wastewaterfire 

You're welcome to send this update to your networks. If you know someone in the community who doesn’t have email or internet access, please print this newsletter off and pass it to them.

If you know of anyone who would like to receive this e-newsletter they can subscribe online. 

If you have any questions, or would like further information on the project, please call us on 03 941 8999 or 0800 800 169 or email wastewater@ccc.govt.nz  

Thanks for your patience and understanding. We’ll be in touch again soon.