Christchurch Wastewater Treatment Plant update

Thursday 12 February 

We're developing a pond management plan 

A pond management specialist is on site with our team today and tomorrow to help develop a new, comprehensive pond management plan. This plan will focus on tracking key indicators – such as algae levels, dissolved oxygen, and other early‑warning signs – as well as making some recommendations so we can act sooner when conditions begin to deteriorate.

The aim is simple – reduce the chance of odour by identifying issues earlier, responding faster, and keeping the community better informed.

We want to reassure you that we’ve already been extensively monitoring these key pond indicators. The new pond management plan builds on this work by strengthening our approach – setting clearer trigger points for when conditions start to shift and outlining earlier, more decisive actions we can take.

Pond system slowly stabilising 

Conditions at the ponds continue to trend in the right direction, with both algae levels and dissolved oxygen slowly increasing. These are positive signs that the system is stabilising, but health indicators in ponds 1, 2A and 2B are still lower than ideal and we continue to monitor them closely. 

There is no change to the pond status map today. We’ll continue to monitor the improvements closely and update the community as conditions evolve.

Latest hydrogen sulphide monitoring 

The latest hydrogen sulphide graph shows that H₂S remains present at detectable levels. Our teams will continue to monitor readings closely and provide updates as trends develop.

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.