How can water spread disease?

ESR scientist Dr Chris Nokes describes why it is important that we manage our water resource so that disease-causing organisms are eliminated from our drinking and recreational water. In New Zealand, we take it for granted that our water is not going to make us sick.

Transcript

DR CHRIS NOKES There are several pathogens that are disease-causing organisms that can be transferred or carried by water. These days, we don't hear much of them in New Zealand, because since the – I guess – the early 1900s, the water supplies have been chlorinated, and that made a big difference to levels of cholera, typhoid sort of diseases that were potentially fatal and carried by water. It is the same throughout the developed world, whereas third world countries have problems with both poor treatment of wastewater, or discharges of wastewater next to, or in, locations that are going to affect drinking water directly after it. So there is a very close link between the potential for disease and faecal matter – that is human waste – and those disease-causing organisms being picked up quickly through drinking water systems.

If there weren't people monitoring the water and providing advice or tools to people who need to treat water, or manage water in general – that is managing catchments as well as water treatment plants – there would be poorer water quality coming through our taps. As a result, levels of water-borne disease would be higher in the community. It is something that New Zealanders tend to take for granted, and first world countries in general, because the real problems with water-borne disease have been essentially eliminated, except for the occasional outbreak because something goes radically wrong. Everybody assumes that water is a free resource that anybody can get hold of, and they don't have to pay for it, and it’s not going to cause them any health problems. But the fact of the matter is there is always disease-causing organisms in the environment that water treatment suppliers and operators are having to eliminate from our drinking water 24 hours a day, 365 days a year. And you know, people, they just don't appreciate the sort of barriers that are being put up between them and disease.

Acknowledgements Anwar Huq Jonathan McIntosh Watercare Services Ltd