Untreated sewage spilled into the Manawatu River and back through manholes in a low-lying Palmerston North street yesterday afternoon.
The city council suspects a power surge caused an outage at the Totara Rd wastewater treatment plant and is investigating.
Water and waste services manager Rob Green said untreated waste was discharged into the river for about five minutes, and up through manholes in Escort Grove.
Council staff unblocked the pipelines and cleaned up the area affected.
Green said a series of back up systems failed to work as well as they should have to prevent the overflow.
Horizons Regional Council has been informed about the discharge to the river.
The damaged circuit board is being fixed, and the plant was running properly by 5pm.
A full review is underway to determine exactly what went wrong.
Residents will receive an apology and reassurance that health and safety protocols were followed.
- Manawatu Standard
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