We're aware of ongoing odour concerns in parts of Middleton and are actively working to reduce them.
Our investigations indicate that the existing odour treatment system at Birmingham Drive may no longer be large enough for current operating conditions.
While we develop a long-term solution, we've implemented a range of measures to improve odour control and are continuing to investigate further options.
What we've found
We've carried out a detailed investigation to better understand the source of odours in the area.
- Inspected wastewater pipelines along Birmingham Drive and Hands Road using CCTV and jet cleaning equipment.
- Investigated nearby businesses to identify any activities that may contribute to odour issues.
- Reviewed pump station operations, including wastewater volumes and pump cycle times.
- These investigations did not identify any conditions or activities that would cause increased odour, and the pump stations were found to be operating as expected.
- Our investigations do indicate that the existing odour treatment system at Birmingham Drive is likely undersized for current operating conditions.
What we've done so far
We've completed several improvements aimed at reducing odour levels in the area, including:
- Installed a temporary odour treatment unit at the Birmingham Drive site.
- Added four additional cubic metres of odour control material to improve treatment performance.
- Installed custom-made carbon filters on the temporary treatment unit vents to provide an additional layer of odour removal.
- Adjusted the temporary unit's exhaust system to direct treated air away from nearby pedestrian areas.
- Sealed a vented manhole on Birmingham Drive to help reduce odour release.
- Installed odour monitoring equipment.
Short-term improvements
We're continuing to investigate additional measures that could further reduce odours, including:
- Chemical dosing with magnesium hydroxide within the wastewater network to reduce odour generation.
- Installing a temporary advanced-treatment odour unit using a two-stage trickle filter system.
- Replacing odour treatment media at the Wigram Road odour treatment facility to improve odour control further upstream in the network.
Long-term solution
A permanent upgrade to the odour treatment system is being prioritised as part of future wastewater infrastructure planning. This work will include:
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Engaging specialist consultants to develop an improved odour treatment solution.
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Developing a renewal and upgrade plan for the existing odour control infrastructure.
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Installing a replacement or upgraded odour treatment system.
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This project will be considered through planning for the Council's Long Term Plan 2027-37 programme.
