Water notice lifted in Lower Waihao

Residents on the Lower Waihao (including Waikakahi East) rural water scheme can now return to consuming water directly from the tap, with Council today lifting their “do not consume” water notice.

Scheme users (approximately 600) have been without potable water since early August, following a significant rain event in late July when nitrate levels were detected above the maximum acceptable value (MAV) of 50mg/l NO3. The current nitrate concentration is 38mg/l NO3.

In response to that situation, Council immediately installed water tanks in Glenavy and Morven and an additional water tap at Victoria Park, ensuring all residents had access to safe drinking water, compliant with the New Zealand Drinking Water Standards. In addition, Council committed to introducing a denitrification process, expected to be complete by mid-2023 – adding to their existing plans to establish a new treatment plant in the area.

However, following months of observation, monitoring and ongoing tests, recent results have now shown the water to be consistently within the acceptable MAV limits, meeting the drinking water standards and proving safe to consume.

Council’s Asset Group Manager Dan Mitchell says despite the reduced nitrate levels, the existing water tanks will remain in place for the next few months – ensuring all residents continue to have access to safe drinking water in the event of another surge or spike in nitrates.

“It’s an important measure to ensure the tanks remain in place until final decisions are made around the operational arrangements and the commissioning of any solution,” Mitchell said.

A community information session will be held at the Glenavy Hall on Wednesday 7 December at 6.30pm, with Mitchell encouraging all residents on the scheme to get along and learn more about the future options available.

“There’s a few options on the table and that’s something we need a steer on from the community. This will be a great opportunity to have any questions answered, discuss ongoing options around denitrification and talk through the supporting science in an attempt to reach a preferred solution,” he said.

“Given that denitrification will have significant capital and operational costs, and the fact current advice is that the MAV remains at 50mg/l, the community will need to make a decision on the level of nitrate removal and how far Council need to go with this.”