Western Wastewater Treatment Plant
At the Western Treatment Plant, sewage travels through a series of screens, tanks, bioreactors, clarifiers and ultraviolet treatments before being discharged as liquid into Cook Strait in the vicinity of the Karori Stream Mouth.
The Western Treatment Plant was granted new consents on 28 July 2010. These consents will continue for 25 years (expire 28 July 2035).
In general, the consents allow Wellington City Council to:
- discharge of treated and partially treated effluent through an existing outfall,
- to discharge mixed disinfected, treated and milli-screened wastewater during and/or immediately after heavy rainfall,
- the discharge of contaminants to the air,
- and permission to occupy the coastal marine area with an outfall structure.
Resource consents
WGN060283 [35675] Discharge of Partially Treated WW to Fresh Water (Western WWTP)
WGN020236 [22098] Land Occupation by Outfall Structure (Western WWTP)
WGN060283 [25227] Discharge of Treated WW to Fresh Water (Western WWTP)
WGN060283 [25230] Contaminants Discharge to Air (Western WWTP)
WGN060283 [35255] Discharge of Treated WW to Coastal Marine Area (Western WWTP)
WGN060283 [35674] Discharge of Partially Treated WW to Coastal Marine Area (Western WWTP)
WGN160340 [34178] [34179] Pipeline Maintenance Land Use (Western WWTP)
Resource consent reports
Annual Reports:
Western Wastewater Treatment Plant Annual Resource Consents Report 2020/2021
Western Wastewater Treatment Plant Annual Resource Consents Report 2019/2020
Western Wastewater Treatment Plant Annual Resource Consents Report 2021/2022
Western Wastewater Treatment Plant 2022/ 23 Annual Resource Consents Report
Western Wastewater Treatment Plant, GWRC Compliance Monitoring Report 2022 - 2023
Plant performance
Current Status: Non-Compliant
Period: June 2024
Commentary:
The plant remains non-compliant for biochemical oxygen demand* 90-day geomean limit and daily BOD results remained above the geomean limit in June. Current sampling results show a trend towards compliance. Additional analysis and process adjustments continue to resolve this issue.
Discharges:
No discharges in June.
Odour complaints
No odour complaints in June.
Items of significance:
Outfall Repair:
Repair work to the main outfall pipe resumed on 15 May, following the agreement with the landowners for access.
Repair work is progressing well and is expected to be completed before the end of July.
This work is required to be completed by 4 August 2024 under an abatement notice issued by Greater Wellington Regional Council.