Dargaville became desperately short of water last week due to significant main breaks in the raw water line, such as this one on Kaihu Woods Rd. Video / Supplied
Kaipara District Council is still investigating what caused multiple leaks in its Dargaville raw water pipeline, cutting water to the majority of residential streets last week.
Councillors have called the emergency “completely foreseeable” given the age of the infrastructure and an “existential threat to the viability of Dargaville”.
The incident started last Wednesday, May 25, when council staff noticed the raw water flow was starting to reduce. The raw water is piped to the treatment plant then stored in a 500cu m reservoir.
The team started checking the 26km raw water line and found a leak but, when they isolated the line, it may have caused a pressure surge, Marris said.
The leak was fixed and the water treatment plant was back in production by 7.30pm on Wednesday.
But on Thursday morning, staff noticed the water level in the reservoir was still dropping and they enacted an emergency response, including getting tankers to cart treated water from Ruawai, Maungatūroto and Whangārei into the reservoir.
The council started messaging the public on social media on Thursday afternoon, asking people to conserve water.
Crews from local firm Harrisons, and Auckland and Whangārei-based Downers worked around the clock to fix the breaks, which could not be repaired until 2am on Saturday.
The incident which cut water to parts of Dargaville could threaten the viability of the rural town, councillors say. Photo / NZME
However, it took a further 16 hours to purge the 26km pipeline of air until water could start flowing properly again, he said.
Marris said the council had to turn off its booster pumps, which pumps water to about 70 properties sitting higher than the reservoir. They were without water from Friday until 5pm Sunday.
As well as using social media and the council website, the response team communicated with properties and residents who really needed water, such as a dialysis patient and the meatworks, he said.
While schools and Dargaville Hospital used their own water tanks, tankers were also sent to the hospital to ensure it didn’t run dry, he said.
Water was fully restored on Sunday evening, but some customers may have noticed discolouration, Marris said.
This was from the turbidity of the water tankers putting treated water into the reservoir, but it was continually tested and “100% safe to drink”, he said.
The raw water pipeline was installed in 1958 and was expected to have a 70 to 80-year life, so it is not due for replacing until 2028 to 2038, Marris said.
An assessment 15 years ago also estimated the pipe still had another 30 years of life.
In the last 12 months, there have been no signs of leaks nor complaints from the public about leaks, he said.
The pipe itself would cost $20 million to replace, and renewals are being budgeted through the council’s long-term Local Waters Done Well plan, Marris said.
Outspoken councillor Pera Paniora says the incident was predictable given Dargaville's ageing infrastructure. Photo / NZME
Te Moananui o Kaipara Māori Ward councillor Pera Paniora said the water outage was disappointing.
“It’s completely foreseeable given that we know that we have failing infrastructure, which was pretty much set up with the inception of Dargaville town being built.”
She asked how the council could identify other pipes in Dargaville that were a “ticking time bomb” and in need of replacement.
Marris disagreed there were any “ticking time bombs” in Dargaville but said a programme of work is in place.
Denise Piper is a news reporter for the Northern Advocate, focusing on health and business. She has more than 20 years in journalism and is passionate about covering stories that make a difference.
