The NSW town of Bundanoon has won international headlines for its vote to ban sales of bottled water, perhaps because the story — small community standing up to big industry — has overtones of David and Goliath, a tale with enduring appeal.

There’s much to be said in favour of grass-root movements that draw communities together and empower them to take action over issues of local or even global concern.

But, at the risk of throwing a wet blanket over Bundanoon, it may be timely to revisit the law of unintended consequences — especially in view of the NSW Premier’s enthusiasm for implementing similar bans elsewhere.

This law states that any purposeful action will produce some unintended consequences. According to Wikipedia, a classic example is a bypass — a road built to relieve traffic congestion on a congested road — that attracts new development and with it more traffic, resulting in two congested streets instead of one.

We’re not fans of bottled water or its environmental toll, but it’s not difficult to imagine that banning its sale might have the unintended consequence of boosting soft drink sales. Not everyone will want to drink from water fountains or go to the trouble of carting around recyclable bottles for filling.

If this is the result, then it would be a worry, given that soft drink consumption is implicated in poor oral health, as well as overweight and obesity, particularly among children and teenagers.

It is noteworthy that many interventions aimed at preventing unhealthy weight gain put a priority on cutting soft drink consumption. This article reviewing the link between soft drinks and weight gain, published in the Medical Journal of Australia in 2006, cited evidence that:

  • 78% of all 12–17 year olds had consumed soft drink in the previous week.
  • Around half of all teenagers and a surprising 26% of 2-3 year olds had consumed soft drink during the previous 24 hours.
  • The intake of soft drinks in Australia has grown rapidly in the past 30 years from around 47.3 L per person per year in 1969 to 113 L per person (children and adults) in 1999.
  • Australia is one of the world’s top 10 countries for soft drink consumption, which represents a market of around $1.6 billion per year.

Given the enthusiastic reception for Bundanoon’s stance, with other towns now considering similar moves it might be useful to have some careful evaluation of the ban’s impact.

Or at least we should be considering measures that dampen sales of soft drinks as well as of bottled water.

Otherwise, Bundanoon may have inadvertently contributed a new twist to an old tale. It may become known as the little town that helped a Goliath grow.

*Melissa Sweet is a freelance heath journalist; Professor Kerin O’Dea, a leading expert on public health nutrition, is director of the Sansom Institute at the University of South Australia.