ORC Modifying Its Shotover Testing Regime

Scoop

a day ago

Otago Regional Council is modifying its testing programme at the Queenstown Lakes District Council owned and operated Shotover Wastewater Treatment Plant near Queenstown with water testing and plant site visits moving from weekly to monthly.
This decision balances the need to ensure a robust monitoring programme which provides assurance to the people of Queenstown and downstream from the discharge, with the need to ensure prudent financial management, where appropriate monitoring and oversight is already in place.
There will still be weekly water testing of the Kawarau River downstream of the treatment plant site and monthly on-site visits and auditing of the plant.
Test results will continue to be made public, says ORC's General Manager Environmental Delivery, Joanna Gilroy.
'Monitoring of compliance on site with the Enforcement Order and consents remains a high priority for ORC.'
'We have confidence in the combination of the sampling required under the Enforcement Order, our continued weekly sampling of the Kawarau at our Chard Road monitoring site plus our continued monthly full site sampling and audits at the plant.'
'This monitoring regime will maintain the high standard expected,' she says.
All the results from the independent lab will continue to be made public and ORC will maintain on-site visits once a month and respond to any complaints, Ms Gilroy says.
Staff will continue to audit sample results and information supplied to Council to ensure compliance.
Monthly sampling, or sampling after any incident, will continue from the established sites; below.
Upstream entirely of the Shotover WWTP and ponds (before the SH6 bridge)
Final discharge post-UV treatment
Discharge to the river (at the last realistic and safe point)
Approximately 200 metres downstream
Upstream of Kawarau River
Downstream of Kawarau River (past Shotover river)
ORC will also continue to monitor the Kawarau River at Chard Road site once a week.
'These sites have been chosen so that any impacts on the Shotover and Kawarau can be monitored. Samples will be taken by ORC staff in line with previous sampling processes and the results will still be analysed at an independent laboratory,' she says.
Once results have been returned to ORC from the lab and checked by staff, they will continue to be uploaded to ORC's Shotover web site.
Ms Gilroy notes the results may not be uploaded on the web site until 10 or more days after the sample is taken, due to lab processing times and the need to consider whether the results may be required to be used as evidence in the future.
Any results and data shown will not give any indication of compliance status, any environmental effect or any potential compliance action, she says.
Background
What monitoring has ORC been doing of the site since before April 2025?
ORC has been regularly undertaking testing to monitor compliance with consented limits and conditions. This occurred at a standard series of locations to enable trend data to be collected. Testing included investigation of E. coli – Escherichia coli, TBOD – Total Biochemical Oxygen Demand, TN – Total Nitrogen, and TSS – Total Suspended Solids.
The samples were analysed based on consents parameters, and, where appropriate, other parameters used to detect wastewater. Sampling is completed by ORC staff in line with sampling procedures and analysed in an independent lab.
From 7 April 2025 a new set of standardised sampling locations were set up to specifically monitor the discharge on site.
These sites will be sampled weekly until 18 August, and will then move to monthly, along with a monthly site inspection.
What monitoring is happening at the Shotover site from August ?
After 18 August, ORC will be doing monthly testing on site to monitor compliance with consented limits and conditions and the Enforcement Order rather than weekly. This will happen at the standard series of locations to enable trend data to continue to be collected. Testing will include investigation of E. coli – Escherichia coli, TBOD – Total Biochemical Oxygen Demand, TN – Total Nitrogen, and TSS – Total Suspended Solids.
Will ORC continue the current monitoring of the site under the Enforcement Order ?
Yes. Under the Enforcement Order, QLDC is required to undertake monitoring on site. ORC will audit this monitoring and the results regularly to ensure that they are compliant and to check for any impacts on waterways. These results will continue to be supplied on this webpage.
ORC will continue to monitor the Kawarau River at Chard Road State of the Environment Monitoring site once a week to ensure the community has access to frequent monitoring results and to continue to provide information to downstream water users.
What information did ORC base its decision on to change the monitoring approach?
With the Enforcement Order in place, as well as the monitoring required under the resource consent, QLDC are now required to undertake a wide range of monitoring and supply these results to ORC.
ORC staff have reviewed what QLDC are required to do under their Enforcement Order; what the results of ORC's monitoring programme to date have shown and balanced this against the continued need to provide information and confidence to the public.
With this in the mind the monitoring for the site has changed to monthly compliance sampling on site and the continuation of weekly monitoring of the Kawarau River at Chard Road will continue.
Will the monitoring approach change again?
Potentially. The approach to monitoring will be reconsidered once any decision is reached on the consent, or if there are impacts on the environment or when upgrades are made at the site.