Kohukohu Wastewater Treatment Plant, Kaikohe-Hokianga Community, Northland

The Kohukohu wastewater treatment plant is located on Motukiore Road in the Kaikohe-Hokianga Community, within the Far North District of Northland, New Zealand. It serves a small population of 700 residents, reflecting its role in a rural coastal community. As a secondary treatment facility, the plant meets the standard required under New Zealand's Resource Management Act, which governs wastewater discharges to protect water quality. For a plant of this scale, secondary treatment is typical and ensures effective removal of organic matter and solids before discharge. The plant's treated effluent is discharged into the local environment, which ultimately drains to the Tasman Sea via the Hokianga Harbour. This harbour is an ecologically significant estuary that supports diverse aquatic life, including migratory fish species and native bird populations. The plant's coastal location necessitates careful management to minimize impacts on the sensitive marine ecosystem.

The Kohukohu plant discharges into the Hokianga Harbour, a large drowned river valley on the west coast of Northland. The harbour flows into the Tasman Sea, providing critical habitat for fish, shellfish, and shorebirds. The surrounding catchment includes native forest and farmland, and the estuary supports important ecological functions such as nutrient cycling and sediment trapping.