We’ve heard much about contamination of water supplies over the last few weeks. So what exactly do we mean when we say contaminated? To me, a contaminated water supply is when the barriers in place are overcome (i.e. the treatment doesn’t remove the contaminant).
If you look in the Drinking Water Standards for New Zealand, there are literally hundreds of potential contaminants from bacteria and protozoa to pesticides and herbicides to all kinds of chemicals and toxins. Some of these are harmful to humans, some make the water look, taste or smell bad and some will stain your laundry.
The reality is we can make any water safe to drink.
Sometimes it’s expensive and sometimes the number of processes we have to use are extensive but we can treat it. We can even purify seawater and make it fit to drink. The contaminated source in Havelock North is only contaminated because there is no treatment in place. The truth about that source is that it is still an excellent source of water and is relatively clean. This means that the treatment required would be cost effective and relatively easy.
Would it involve chemicals? Probably it would and the final treatment would undoubtedly involve chlorine if the choice was left to any reasonable water supply engineer. If you don’t like the taste of chlorine, put a carbon filter before your tap. This will remove all the chlorine very effectively but will still mean that the water delivered to your house is safe to drink.
If we get upset over every contaminant in the source water, we’d never drink water again. The Waikato River, for example, has elevated levels of naturally occurring arsenic. Should we be concerned? No, because the treatment processes remove the arsenic extremely effectively - there is absolutely no arsenic in our drinking water.
If you add up all the water takes from the River Thames in London, it’s seven times the river flow. What this means is that the water has been taken out of the Thames, then treated, used, treated again and put back in the Thames seven times. Or put another way, it has been through seven sets of kidneys.
Can we afford this treatment of all our supplies? With the funding models we have now, the answer is an emphatic no. But we should look at other water suppliers around the world and see what they’ve done. Our water supply services are in a very similar state to the water supplies in Scotland in the 1970s. Scotland has one water supplier now after a series of amalgamations starting at a council level and through larger and larger entities until everyone worked out that a single supplier was the answer. This has led to the Scots having a consistently safe water quality across the whole of Scotland no matter how small the community. We don’t have to go through 40 years of pain and agony to figure this out – we could go straight to the solution.
The problem is that this needs leadership at a national level not at a local or regional level.
To have a national SOE for water is a good thing in my opinion. However the other side of Scotland’s model is a strong regulator. Here we have the Ministry of Health for the Drinking Water Standards, the Regional Councils for the environmental compliance, the Ministry for the Environment, Department of Conservation, MBIE, and the list goes on and on. It’s too confusing to be a workable model. The one thing we don’t have really is an economic regulator – odd?
Scotland has a single overarching independent regulator that has a number of parts including an environmental regulator, an economic regulator and a drinking water quality regulator.
My hope for the enquiry into the Havelock North event is that it looks forward and asks some of these hard questions. But if it only asks only one question, let it be, ‘Should the safety of our drinking water supplies be left in the hands of politicians who are elected every three years?’ This is not a call for reform of our electoral process but a call for independence of our water supplies from political interference.
This thought leadership article by Iain Rabbitts, a water and wastewater manager in our water resources team, is intended to provide you with insights and relevant information on the Havelock North water crisis. Our thought leadership articles on topical and specialist issues are designed to present the key points in an easy to digest and interesting manner.
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