An independent inquiry is under way into why fluoride was turned off at two treatment plants without residents being told. Photo / 123rf
An independent inquiry is under way into why fluoride was turned off at two treatment plants without residents being told. Photo / 123rf
Wellington Water has called in divers to assess the damage to fluoride facilities in a reservoir the size of two Olympic swimming pools.
The company is under pressure after fluoride was turned off at two water treatment plants supplying Upper Hutt, Porirua, and Wellington City without anyone being told.
An independent inquiry began after incorrect information that fluoride had been turned off in February this year, when it had actually ceased at Te Marua plant last May and at Gear Island in November.
Before that Wellington Water had been "nursing" the ageing and unreliable infrastructure by being conservative with fluoride dosing.
While the inquiry plays out, Wellington Water is moving "at pace" to return fluoridation to residents.
Chief executive Colin Crampton told the Herald that divers did an assessment of a baffle curtain at Te Marua plant last month.
A baffle curtain works by slowing the flow of water, allowing the fluoride powder time to settle and filter. This prevents the powder clumping and gives operators control of the mixing ratio.
Two divers went into the treated water reservoir at the plant where the baffle curtain is, Crampton said.
The reservoir holds 5 million litres of water, which is the equivalent of two Olympic-sized swimming pools.
The divers were supported by a full crew including two other standby divers, Crampton said.
"The divers carried out a visual survey of the damaged baffle curtain, confirmed the size of the curtain, and took camera footage to assist engineers in their condition assessment."
Wellington Water chief executive Colin Crampton. Photo / Mark Tantrum
Crampton said the plan was to repair the damaged sections of the curtain and have them refitted by the end of this month.
The entire operation of the facility then needed to be checked to ensure it could be put back into operation safely, he said.
"This process can take time, but it's important that we do it right. We'll have a better idea of when we can get the fluoride facility at Te Marua back in operation in the coming weeks."
While this is under way, Wellington Water will also procure a replacement curtain to provide a medium-term solution.
Over at Gear Island, the fluoride system will be replaced with a new one that can be housed in a shipping container to get things back up and running as soon as possible.
That's because the existing concrete ceiling at Gear Island has deteriorated so much that workers cannot safely access the fluoride room.
There are also storage compliance issues related to the positioning of the fluoridation tanks, which are beyond their use-by-date.
Crampton said the new system would be plumbed into the plant and bypass the existing fluoride facility.
"Due to global supply issues, we can't provide a firm timeframe at this stage of when this new system will be in place. Once we know more, we will provide the public with timeframes."
Yesterday Wellington Water released the terms of reference for the independent inquiry, which will look at the failure of management to inform the board, councils, and the public of its decision to cease fluoridation in a timely manner.
The scope also provided the opportunity to probe broader systemic matters considered relevant to the review.
The reviewer, Doug Martin from MartinJenkins, has been authorised to obtain documentation as well as conduct interviews with relevant staff and stakeholders.
The inquiry's final report is due by May 31 and the findings will be made public.
Deputy Prime Minister and Wellington Central MP Grant Robertson has labelled the situation "ridiculous" and has said Wellington Water has a lot of explaining to do.
The New Zealand Dental Association has said it's "greatly alarmed" by the decision to switch off community water fluoridation, which will affect communities already impacted by oral health inequalities.
Crampton said Wellington Water was committed to restoring fluoride at Te Marua and Gear Island water treatment plants as soon as possible.
