Twizel Water Plant Failure Leaves Residents Dry and Highlights Infrastructure Vulnerabilities

A sudden failure of UV intensity sensors at the Twizel water treatment plant left the town dry on Tuesday, highlighting the lack of a treated water reservoir.

By: AXL Media

Published: Apr 11, 2026, 4:58 AM EDT

Source: RNZ Pacific

Sudden Shutdown and Community Response

The outage began around 6:00 pm on Tuesday, with dozens of residents taking to the "Twizel Community" Facebook page to report low pressure or a complete loss of water. Jacqui De Buyzer, vice-chairperson of the Twizel Community Care Trust, stepped in to coordinate information after after-hours council lines became overwhelmed by callers.

The council dispatched a response team, with members traveling from as far as Fairlie over an hour away to address the fault. By 7:30 pm, the issues were largely rectified, though the process of recommissioning the network took additional time to ensure the removal of air pockets that could cause pipe bursts.

Technical Cause: UV Sensor Failure

Mackenzie District Council's general manager of operations, Neil Jorgenson, explained that the shutdown was an automated safety response. The plant utilizes three parallel "trains" of UV units to disinfect water, all of which are monitored by intensity sensors.

The Fault: New sensors were installed on Tuesday as part of a routine replacement the first since the UV units were originally commissioned.