Huntly's tap water has been running brown since 2015. Photo / Danielle Zollickhofer
After a three-year wait for a specialised machine, Waikato District Council has started flushing Huntly’s water pipes this week, with residents hoping the wait for clear water is over.
In the past 10 years, the council recorded more than 600 official complaints about Huntly’s water, mostly because the tap water regularly runs brown, has a metallic taste and discolours washing, leaving residents worried about bathing in it, let alone drinking it.
One resident said that since March this year the water had been “the brownest” she had seen it.
The council said the discolouration was caused by iron and manganese deposits in old pipes but the water was “safe to drink”.
In the hope of rectifying the issue, the council requested a specialised machine, called a no-des unit (Neutral Output Discharge Elimination System), in 2022.
The unit, owned by a private company called Detection Services, is New Zealand’s only one and arrived in the country in October last year.
This week, the council said it had now been able to use the unit to flush and remove mineral deposits from the water pipes.
The council’s waters manager Keith Martin said the water for Huntly residents was taken from the Waikato River and the intake was “below the Mangawara stream in Taupiri”.
This stream had high levels of manganese, which was a naturally occurring mineral.
Martin said dissolved minerals built up in the pipes, and eventually dropped and were swept by the water flow, causing the water discolouration.
“Even though the water is still safe to drink, we know that the water colour is off-putting for people.”
This was why the arrival of the unit was great news.
“The unit connects hydrant-to-hydrant, uses reverse flow to scrub the sediment build-up off the pipes and then filters it out.
“The process filters out debris with minimal water loss and will target key areas in Huntly to improve water quality across the network,” Martin said.
However, some residents are concerned whether the unit will fix the issue.
Huntly resident Joanne Kelly, said for her, the issue had yet to improve with brown water still running through her tap this week.
“There’s just no trust there because my water is still brown, and nothing has changed.”
Huntly-born resident Awhina, who did not want to give her last name, told the Herald she was the fifth generation of her family to live in the district.
In the last decade, she started noticing brown water that looked like “mushroom soup without the cream” in her taps and a smell she described as similar to chlorine.
Due to this, she uses bottled and filtered water to drink, but continued to see brown water when running a bath, and she noticed the unusual smell “almost every day”.
When asked how she felt about the flushing having started this week, Awhina said she was unsure.
“It’d be interesting to see what [the unit] actually does, I think it’s more than just minerals.
“But if it does work, that’ll be awesome.”
Martin said in addition to the flushing, the council had been undertaking “a programme of work” to improve the water supply in Huntly, including upgrading water lines and flushing pipes regularly.
This had resulted in fewer brown water incidents, the council said.
While the no-des unit is in use, Huntly’s water supply wouldn’t be affected, the council said but there may be traffic disruptions.
Signs and traffic management were in place.
Work was planned to be completed by the end of the week.
The specialised unit has been used by a number of councils around New Zealand and Australia.
Waikato District Council plans to upgrade the water treatment plant in the future to deal better with manganese deposits.
Malisha Kumar is a multimedia journalist based in Hamilton. She joined the Waikato Herald in 2023 after working for Radio 1XX in Whakatāne.