We've come to known Wellington's water woes as wastewater spewing into the harbour, broken sludge pipes, and geysers erupting in streets, but little did we know the biggest scandal was still lurking beneath the surface.
The findings of an independent review released this month reveal water in the region hasn't been fluoridated properly for six years.
This failure is far worse than any of the broken pipes the city has experienced to date.
Because while none of these woes have made people sick from contaminated drinking water, ineffective fluoridation does have health consequences.
Doctors fear the extent of the fluoride failure could cause an upswing in tooth decay in children, which is likely to affect those who are already struggling the most.
Dental health is consistently among the top three reasons Porirua children under the age of 5 are admitted to hospital for conditions which could have been avoided with earlier access to primary healthcare.
Māori and Pacific children in Porirua have much higher rates of tooth decay at age 5 than European/Pākehā children.
Dental care is free for children up until the age of 18 in New Zealand. I remember going to the dentist at university for the first time in years, after delaying doing so because I was nervous about how much the bill would be.
As soon as the dentist looked in my mouth she asked whether I had grown up with fluoride in the water, which I had.
It remains a clear memory for me because I was amazed by how obvious the effects of fluoridation were.
I am saddened that other kids growing up in Wellington are not receiving the same benefit that I did.
Parents had a right to know their children were not drinking water with adequate levels of fluoride in it so they could compensate for it.
The investigation into the failure was launched after Wellington Water staff turned off fluoridation facilities at two treatment plants last year and didn't tell senior leadership, the board or shareholder councils.
The report found the water company lost sight of the importance of fluoridation, partly due to weak regulatory settings.
Regulation has focused on the safety of drinking water and only ensured it was never over-dosed with fluoride.
It astounds me that so many people were concerned about putting too much fluoride in the water, but gave little thought as to why it needed to be added in the first place.
Oral health benefits to one side, it is even more baffling to me how no one thought about the risk associated with these decisions given fluoridation can be such a controversial issue.
It only gets worse.
Wellington Water employees at an operational level not raising concerns is one thing, Regional Public Health (RPH) behaving the same way is another.
It turns out RPH also knew about this since 2016, but did not sound the alarm.
This is an organisation that was created to "promote good health, prevent disease, and improve the quality of life for our population".
As the regulator, RPH too was following rules that focused on ensuring water was never over-dosed with fluoride.
But surely someone working at a public health organisation would spare a thought for the oral health benefits too? Apparently not.
Ironically, RPH no longer exists under the Government's new health reforms and neither will Wellington Water when Three Waters reforms come into force.
In the meantime, everyone at Wellington Water is keeping their jobs after taking "collective accountability" for the failure and publicly apologising.
In different circumstances, there might have been calls for the chair of the Wellington Water board to resign.
Current chairwoman Lynda Carroll is a relatively fresh face who only took over the role in November.
The fluoride failure raises a dilemma at a governance level both for the board and councils.
They assumed water was being fluoridated when it wasn't, so they will be questioning what else they need to poke holes in, while also ensuring their actions don't become an intrusive overreach.
The board has accepted all of the review's recommendations and is moving to implement them, including having a "relentless focus" on fluoridation.
They are working to reinstate fluoridation by September.
This focus is a welcome change from some attitudes revealed in internal emails at Wellington Water, where escalating the fluoride failure to senior leadership languished on a staff member's "to-do-list" for weeks.
After sifting through the findings of the independent review, subsequent interviews, and correspondence, I still can't believe this happened.
It really is a colossal failure in a league of its own.
• Senior Wellington journalist Georgina Campbell's fortnightly column looks closely at issues in the capital.