The water debate continues

Saturday January 04, 2020 Written by Published in Opinion
Ani O'Neill, Christina Maclennan, Missy Vakapora, Andy Kirkwood, Renall Vogel, Robert Wigmore, Io Vakapora were among Te Vai Ora members who staged a protest against government turning on the taps of the new filtered water intakes, early in December. 19120201 Ani O'Neill, Christina Maclennan, Missy Vakapora, Andy Kirkwood, Renall Vogel, Robert Wigmore, Io Vakapora were among Te Vai Ora members who staged a protest against government turning on the taps of the new filtered water intakes, early in December. 19120201

 

Several weeks ago, the Cook Islands water authority, To Tatou Vai, announced it was conducting a six-month trial of Poly-Aluminium Chloride (PACl) as a flocculation agent. 

Flocculation is a process of settling out particulate matter, for example dirt, from the water. Given that PACl is a chemical that produces a potentially toxic sludge as a byproduct of the flocculation process, this trial needed to be properly assessed for environmental impacts before it was approved.

 

The purpose of an Environmental Impact Assessment (EIA) is to ensure that decision makers consider the environmental impacts when deciding whether or not to proceed with a project.  It also ensures alternative options are given adequate consideration.

A simple Google search will find scientific papers that question the impacts of PACl on freshwater ecology, and suggest that its potential impact should be assessed for each specific location where it may be used.

As this has not been done in Rarotonga, how do we know that chemicals are not finding their way into our streams, having a negative impact on our freshwater ecology, including koura vai (prawns), tuna (eels), and freshwater fish. 

Another purpose of an EIA is to look at alternatives that may have a lesser negative impact. Therefore, from an environmental perspective, the logical thing to do to reduce dirt getting into the water is to first trial alternatives which provide a lower level of risk to our freshwater ecology. 

Te Vai Ora Maori community group have suggested one such alternative to flocculating chemicals.  Their idea is simple, and involves diverting the dirty water that we sometimes get after heavy rain until it is clear again. That way, only water relatively free of sediment would end up in the storage tanks. There should be sufficient water storage at each intake, with the new massive storage tanks recently installed, to allow for a sufficient supply for the few days until the water runs clean again.

It would seem to be a more logical, and less controversial, approach to trial this method for six months rather than starting off with a trial on the use of chemicals that so many people do not want.This sort of alternative would have been considered if a comprehensive independent EIA (not the less-effective type of EIA currently practiced in Rarotonga) was commissioned at the beginning of the full water upgrade project, rather than piecemeal EIAs for some stages, and no EIA at all for other stages of the project, such as chemical treatment of our water. 

Another question that could be answered as a part of an EIA is, “what is the current chemical analysis of our natural water?”

Have any studies been done to see what minerals occur naturally in our water? Are some of these actually beneficial to our health, and will they be removed by the PACl? 

If the government would ensure that adequate and independent Environmental Impact Assessments were conducted for all major proposals such as this, it would go a long way to restoring the confidence of the public that the appropriate decisions are being made for environmentally sustainable development of the Cook Islands.

- Te Ipukarea Society

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