Ponds 2a and 2b nearing 'orange' benchmarks

Now that the new activated sludge system is allowing better-quality wastewater to enter the ponds, the health of the ponds is slowly recovering.

We're seeing some encouraging improvement from ponds 2a and 2b, but unfortunately they're not yet meeting the benchmarks we've set for dissolved oxygen and biological oxygen demand (BOD5).

Pond health has to hit both benchmarks before we turn the pond 'orange'.

We’re also monitoring a range of other indicators that help us understand the health of the ponds. These include suspended solids, pH levels, sludge levels, nitrogen and phosphorous levels, enterococci and fecal coliforms.

Now that more, better-quality wastewater is flowing into the ponds, we expect to see the ponds starting to change to 'orange' next week.

The ponds are recovering slowly and although it's now likely some odours will remain for most of September, these will progressively reduce as the pond health improves. Warmer weather and increased sunlight hours will also help the ponds improve faster.

We know this is not the news people want to hear, but we're doing everything we can to improve the biology of the ponds as quickly as possible. 

It will also take another couple of months for the biological health of the ponds to return to a level of resilience where they’re capable of handling increased organic loads if there’s a temporary failure somewhere in the treatment plant process.

We intend to only turn a pond 'green' when there are higher levels of dissolved oxygen present and its biological health reaches this level of resilience.

Community support package closes

The Wastewater Treatment Plant Fire Community Support Package wrapped up this week, with the application period for out-of-zone residents closing on Wednesday 31 August at 5pm.

We experienced a late rush of out-of-zone applications up until the deadline. We're still working through these applications, so will provide a final total number of households who received the support payments in next week's e-newsletter.

We want to say a big 'thank you' to the four community providers – Bromley Community Centre, He Waka Tapu, Ngā Hau E Whā and The Loft – who helped distribute the funds to the community since the support package was launched in May.

There are still support avenues available if your health and well-being are still being affected by the odours. Click the green button below for more information. 

Updated air quality testing results

We’ve uploaded last week's data for the six continuous air monitors that have been set up near the Christchurch Wastewater Treatment plant.

The monitors are to detect the levels of hydrogen sulphide in the Shortland Street, Maces Road, Estuary Road South, Rudds Road areas, as well as at Bromley and South Brighton Schools.

Note the readings online are only up until Friday 26 August – we'll publish graphs showing this week's increased levels of hydrogen sulphide early next week once the data from all of the sites has been collated.

You can read the data for all six locations, and an explanation about how to read the information by clicking the link below. You can also find past readings for each site.

Stay updated

We want everyone to be able to stay updated on our response and recovery from the treatment plant fire, and we regularly post new information and reports on ccc.govt.nz/wastewaterfire 

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 in advance for your patience and understanding as we continue to work on minimising the unpleasant smells after the fire. We’ll be in touch again soon.