Dams are spilling as normal

The Auckland region’s public water processor and supplier is advising that its dams and plant are coping with the huge deluge of rainfall over the past week.

Watercare said on February 13 that heavy rain had been falling regularly in the Hunua Ranges over recent days and it was ‘‘reassuring residents that the dams are operating normally’’.

Total dam storage levels were at 95.7 per cent, ‘‘and the dams are spilling in the normal fashion’’, it said.

However, Watercare water operations manager Priyan Perera said local Hunua residents living downstream from the dams ‘‘should still keep an eye on the weather’’.

‘‘We’re experiencing very heavy rain at the moment, so if you live near a waterway such as the Wairoa River [in south-east Auckland], it’s always a good idea to monitor water levels and take appropriate safety measures.

‘‘But I want to emphasise that the Hunua dams are not used for the generation of hydro-electric dams and operate in quite a different way,’’ Perera said.

‘‘Rain falling in the catchment is stored in the reservoir created by the dam structure, rather than discharged directly to a stream or river.

‘‘There are no ‘release gates’ installed in Auckland’s water supply dams.’’

Tuesday’s advisory came after the Tasman Tempest slowed the Ardmore Water Treatment Plant’s ability to process clean water in March last year.

The plant’s water has been sourced from four storage dams in the Hunua Ranges.

It was treating 50 per cent less water than usual in the wake of those storms that battered the region.

Dam water flowing into the plant post-storms in March 2017 contained a lot of silt due to slips and erosion, making it more difficult to treat.

Watercare monitored dams 24 hours a day and updates are posted daily on its website, www.watercare.co.nz.