Council manages six reticulated schemes in the Grey District for the collection, treatment and disposal of sewage (wastewater). They are:
- Wider Greymouth area (Greymouth, Cobden, Blaketown, Boddytown)
- Karoro, South Beach, Paroa
- Runanga/Dunollie
- Moana
- Blackball
- Iveagh Bay (Te Kinga)
Privately owned septic tanks are used in townships without reticulated schemes.
Each sewerage treatment plant is funded by a targeted rate charged to ratepayers able to connect to that scheme. The targeted rate funds the maintenance and development of wastewater storage, pipes, pumps, and treatment plant and processes.
Council's approach to managing wastewater is detailed in the Annual Plan and Long Term Plan.