Drinking Water Quality in June 2018

May 2018 was full of knowledge sharing in Australia and New Zealand:

  • The Australian Water Association held OzWater’18 Conference in Brisbane.
  • The LGNZ Water Summit 2018 was in Wellington at the end of the month.

Here are some of the interesting parts of each meeting. (We will share more next month as well.)

Sending E. coli samples to the lab is the only way, right?
What are emerging contaminants and why do we care?
What is the New Zealand Government going to do post-Havelock North?

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Sending samples to the labSending E. coli samples to the lab is the only way, right?

Not any more.
The most exciting bit about the trade show part of Ozwater was the plethora of technologies that are now available for analysing drinking water quality.

Historically, the only data we have typically collected on a regular basis was:

  • Retrospective – for example, pH and conductivity only monitored by grab sample, at the sampling frequency of E. coli testing
  • Not timely – E. coli and Total Coliforms results 24 hours later
  • Double-handled by a sampler and lab staff (increasing risk of errors)
  • Not in the field – samples sent to labs introduces delays between sample and results, also introduces opportunities for contamination.
  • Concentrated on the output of the treatment plant – minimal sampling in the extended network because of extra cost.

Sure, there were plenty of other tests we could run and analysers we could install, but they haven’t been cheap, and the sampling frequency so low, the data didn’t help us much.

What if instead, we had affordable access to this:

  • On-site, affordable microbiological testing
  • Mobile units for microbiological testing and other parameters such as FAC or EC, pH (so can increase sampling to the extended network cheaply)
  • Rapid results for microbiological testing, and continuous online monitoring for other parameters.
  • New Zealand Ministry of Health and US EPA approved for use
  • User-friendly interface and automated analysis of data (taking all the guesswork out of the numbers)

Then we could start seeing trends and seasonal variations more clearly. Most importantly, we would know about significant changes quickly, so we can respond!

There were no “perfect systems” who could do all of these in one box yet, BUT depending on what you already have in place, these technologies could get you pretty close. Some of the suppliers who had interesting technologies were:

To be clear – I have no affiliation with any of the suppliers. Also, the market is moving so quickly, if you are reading this even 6 months after publishing, it’s probably out of date. I’m only discussing this so at the next budget/contract review for your laboratory, you know there are many options out there and it is worth investing a little bit of time to research it.


Emerging_ContaminantsEmerging Contaminants

In New Zealand, there has (rightly) been much focus on dealing with bacteria and protozoa, since the findings of the Havelock North Inquiry. Introduction of basic treatment across the country will need large-scale investment.

But if the industry is going to invest in infrastructure, it’s best to future-proof it. (Provided it doesn’t cost too much or distract from dealing with the microbiological contaminants.)

So what should we consider to prepare for the future?

Universities and large utilities are investigating “emerging contaminants”, to identify the contaminants having long-term chronic effects. Some of these contaminants are new and some were previously not identified.

Why is this important? Well, we all drink water, every day. That means that even trace amounts can accumulate and have significant impacts on our health over time. So while acute sickness like what happens with campylobacter outbreaks don’t occur, that doesn’t mean there aren’t chronic impacts.

Emerging contaminants include:

  • Microplastics
  • Engineered Nanoparticles
  • Resistant bacteria
  • Hormones like 17β-estradio
  • PFAS (Perfluorooctanoic Acid – PFOA, Perfluorooctane sulfonic acid – PFOS)

Ok, so PFAS are no longer “emerging” contaminants, they’re a known issue. But multiple papers discussed it and isn’t on the list of contaminants in the NZ Drinking Water Standards at the moment. So for New Zealand, it is an emerging contaminant of sorts.

The Ministry of Health has accepted the Australian drinking-water quality values for PFOS and PFOA as interim guidance levels – as neither New Zealand, nor the World Health Organisation currently have set maximum acceptable values for these chemicals in drinking water. These interim guidance levels will be reviewed as part of a wider review of Drinking-Water Standards, being undertaken as one of the actions arising from the Inquiry into the Havelock North Water Contamination Event.

What are the health consequences?

We don’t know all the health consequences, hence the investigations. But some of the known issues include:

  • Antimicrobial resistance is expected to cause deaths in water supplies. The US Centre for Disease Control and Prevention has identified the resistant Clostridium difficile as an urgent threat level for drinking water.
  • While microplastics have some toxic effects they also can be vehicles for bacteria and viruses, allowing the pathogens an easier route into the victim.
  • Engineered nanoparticles are a multi-billion-dollar industry aiming research at developing particles with different properties, including some designed to pass through healthy cell walls and membranes, that pathogens can’t usually penetrate.
  • PFAS are known carcinogens and with a very long half-life, once they are in a groundwater source, extensive treatment is the only option.

Are they in the catchments in New Zealand?

While groundwater sources with old water, and surface water sources with pristine catchments, protect against microbiological contaminants, they don’t guarantee clean water from tiny contaminants with such long half-lives.

Another issue is that as the population increases and the industrial and agricultural demands on resources increase, there are many more chances of these contaminants entering the sources. We must face the reality that the “clean green” status of the environment here will not remain without significant effort in catchment management, but also, treatment of risks further downstream.

For example, the biggest source of microplastics is not the plastic bags from supermarkets. It’s clothing. Every time you wash most modern fabrics, microplastics leach out as minute fibres. Wastewater treatment plants don’t remove most of them. And aquifers appear to have limited effectiveness in containing them. How confident are we there aren’t microplastics in the drinking water now?

How do you future-proof infrastructure investment?

The treatment processes for these emerging contaminants is very different from conventional treatment for microbiological pathogens. Largely because the inactivation/kill methods of disinfection have minimal impact. The contaminants need to be removed or degraded instead. Flocculation and sedimentation appear to have minimal effect – Granulated Activated Carbon (GAC) and Reverse Osmosis (RO) show the best removal results.

These technologies aren’t a very cost-effective solution for small water suppliers currently.

But, the cost of technology, both upfront capital expenditure, and ongoing operating expenditure, is falling all the time. And suppliers now house the off-the-shelf technology in 20- or 40-foot containers. So the proportion of the total cost for the installation of the civil and building works is growing.

The simplest way to future-proof?

  • Make sure there is room for a filtration or GAC unit later. And the capability for connecting in, bypassing the existing treatment and other configuration issues for retrofitting equipment.
  • Control the catchment where you can to minimize the contaminants getting in there in the first place. Though this is increasingly becoming unrealistic as the only measure, because the number of contaminant types is constantly increasing, and we don’t even know all the sources or routes of ingress.


The microbiological contaminants we are discussing in the chlorine/UV/filtration debate are the tip of the iceberg. And the rest of the berg isn’t exactly made of the same stuff. We need to be thinking about what other countries are saying is already here.

Let’s think about future-proofing our water supply systems by allowing for easier expansion of treatment trains later.

New Zealand government response-post-havelock-north

What is the New Zealand Government going to do post-Havelock North?

Since the incident in August 2016, there have been numerous reports and inquiries, with many recommendations. At the end of May 2018, Local Government New Zealand (LGNZ) and Water New Zealand (WaterNZ) held a summit to explore many of the key issues raised in these reports. Here is the full programme of talks and presenters.

But what should be the top priority for Central Government?


We think it is very important to get the regulations and funding model right, and that this should be the top priority.


Imagine you are the Asset Manager for a small to a medium-sized council.

You know to be sure you are providing safe water, the system needs a new treatment step. You put together a business case for why the Council needs to put extra funding into capital and ongoing operational expenditure.

In Council Chambers the conversation would (legitimately) go along these lines:

“Did we meet the regulators’ requirements last year?”
“Yes, we were compliant”
“What’s changed?”
“ummm… Nothing”
“If the standards and requirements haven’t changed, why should we take money out of other services for this?”

There aren’t many Councils who will prioritise an “optional” water quality investment over improved roads and community facilities. Different funding mechanisms are needed regardless, but they are needed even more if the regulation isn’t changed significantly.

LGNZ came to a similar position before the summit: Water quality framework needs improvement

Our Founder – Carly Price – was a regulator in NSW, Australia for 7 years, and she thinks too much responsibility is put on the individual asset owners in the current system. Saying “they can always do more than the standards require” does not help the asset managers get resources and funding from competing services. The overall change in the industry needs to be driven by the regulatory requirements and the Central Government.

But what changes should happen?

There are many different models of regulation and funding. Every developed country has a different model. In federations there are often multiple models within the one country – for example, there are at least 6 different models in Australia alone. It’s time to look closely at the good and the bad bits of different models and make one that fits the New Zealand context.

The Minister of Local Government agreed with there are lots of options to consider in her speech. She is expecting Ministers to report back to Cabinet later this year on high-level options. Hopefully, the options will provide improvements so water suppliers can get the funding and resourcing they need to deliver safe water to all of us.

So what is the Government going to do post-Havelock North?

We will have to wait and see.

Let’s hope they don’t let a crisis like Havelock North pass by without making significant improvements to the system – as a country we owe that to the victims.


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