Seaview Wastewater Treatment Plant
The Seaview Wastewater Treatment Plant serves a population of about 160,000 in Upper Hutt, Lower Hutt and Wainuiomata. The wastewater is treated or cleaned through a series of screens, tanks, bioreactors, clarifiers and ultraviolet treatments before being discharged into the open sea near near Pencarrow Head/ Te Raeakiaki where it is quickly diluted.
For more information on how wastewater is treated, go to the treatment process.
One of the nine resource consents permitting the operation of the plant, consent ‘WGN120142 [33408] Discharge Treated Wastewater to Stream ' expired in 2018. Prior to the expiry of this consent, Hutt City Council applied to Greater Wellington Regional Council (GWRC) for a new consent to temporarily discharge treated wastewater to the Waiwhetū Stream. While the reconsenting is underway, we continue to operate under the existing consent.
In general, the consents allow Hutt City Council to:
- discharge treated and partially treated effluent through an existing outfall,
- discharge mixed disinfected, treated and milli-screened wastewater during and/or immediately after heavy rainfall,
- discharge mixed disinfected, treated and milli-screened wastewater during maintenance,
- discharge of contaminants to the air,
- and to occupy the stream and coastal marine area with an outfall structure.
Join the Seaview mailing list
If you want to receive notifications and updates about the plant, please email customer.notifications@wellingtonwater.co.nz
Seaview Wastewater Treatment Plant monthly newsletter
For more information about plant activity and projects please go here
Odour treatment
Work is continuing to improve the capture of odours beyond the plant boundary.
Find out more about what’s planned and underway on the project page https://www.wellingtonwater.co.nz/projects/seaviewwwtp
The latest updates are available here
Investigation Reports
Seaview Wastewater Treatment Plant - Odour Investigation - June 2023
Seaview Wastewater Treatment Plant -Biofilter Flow Assessment -March 2024
Making a complaint
If you have a complaint about Wellington Water directly, please call 04 912 4470 or email customer@wellingtonwater.co.nz to access our free complaints process.
After hours, please contact the Hutt City Council Call Centre on 04 570 6666 / 0800 488 824.
Greater Wellington Regional Council is the regulatory agency for reporting airborne discharges 0800 496 734.
Complaints to the Seaview Wastewater Treatment plant can be sent to the following contact details:
First point of contact: Veolia Duty Manager - Call 0800 928 371.
Veolia's Duty Manager contact number operates 24/7 as such complaints can be directly forwarded to them especially if the complaint is urgent and/or happened after office hours.
When a complaint is received, the following information will be recorded:
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Name
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Contact details of the customer
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Nature of the complaint
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Date and time
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Location
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Complaints shall be actioned within 24 hours upon receipt and the records being written to the plant's operational incident log. Odour and/or wastewater discharge complaints will be forwarded to the regional council.
Monthly reporting summary
Plant performance
Current status: Non-compliant
Commentary:
The plant remains non-compliant for faecal coliforms (90-day geomean, 80th percentile limit). Improvements have been observed in the biological process with the plant’s daily effluent results currently within the consent requirements.
Discharges:
There were two consented discharges of fully treated effluent to the Waiwhetu Stream on 1 May & 22 May due to high rainfall within the catchment area.
Formal Warnings & Please Explain letter issued:
Two formal warnings were issued by GWRC for the undisinfected discharges that occurred in January and March of this year.
GWRC also issued a please explain letter in relation to the non-compliant effluent quality being released from the plant. A response was provided within the required timeframe.
Odour complaints:
The plant received 2 odour complaints in May.
Items of significance:
Odour Treatment Project
The project management plan has been finalised and have identified the five priority work packages to be undertaken under this project. One of the high priority package will be undertaking the biofilter “plenum” structure replacement and improvement in cell isolation. The physical works related to this work package will start in winter.
Community Updates
A regular monthly newsletter for the Seaview WWTP is being provided to the interested parties which contains the plant’s operational performance and projects updates.
What has been completed:
The project webpage has been updated with current information to improve the user experience and better inform the public.
A report assessing the effectiveness of the biofilter media replacement has been uploaded into the Seaview WWTP webpage.
The wastewater screening room and dryer building have undergone 3D scan which will be used for ventilation design and screening room ducting replacement.
The external ducting condition assessment has been completed revealing only minor leaks rather than need for full ducting replacement.
The biofilter plenum replacement design has been completed and is undergoing peer review.
What is currently in progress:
The odour scouting programme continues.
A public tour of the plant is planned for 22 June, an invitation has been sent to interested parties and will also be shared on social media.
Biofilter plenum design is currently undergoing peer review.
Resource consents
Resource consent reports
Te Whatu Ora - Health New Zealand statement on the use of the treatment plant deodoriser
Summary
Potential health concerns associated with exposure to quaternary ammonium compounds are most likely associated with direct contact with undiluted product i.e. the staff preparing the solution. Staff exposure risk is managed by following the correct health and safety procedures. Quaternary ammonium compounds are often part of household cleaning and disinfection products and so exposure to the public is relatively common. Given the level of dilution of the product used in the cannon, and the distance between the placement of the cannon and potential locations for public exposure (typically this type of cannon dispersal method has an estimated droplet range of 50-100 metres) that effectively dilutes the strength further, we would not expect this to represent a health risk for the general public.
Te Whatu Ora - Health NZ
April 2023