A few months back John Key visited a port that seemed to defy all logic. It had a number of wharves, dispatch docks and cranes but there was no water.

It was one of the biggest inland ports in the world in China. The only water on offer though came in a bottle and on the label we were told it came from one of New Zealand's deepest aquifers where it had flowed for over 1,800 years and was purified by volcanic rock.

To the initiated it tasted pretty much like good old Kiwi tap water but it raised that old bogey that's confronted John Key ever since he slipped into his leather executive chair on the Beehive's ninth floor: Who owns the water?

Key was adamant, as he's always been, no-one owns the water. If they started charging for it then a lot of people would end up paying.

He'd certainly get no argument from beer drinkers on that one. The amber liquid's made up of 95 percent water and if there was a charge for it, the cost of guzzling through the 65 litres we down every year, would be prohibitive.

But the PM would get an argument from many of us who think that the increasing number of Chinese companies who've taken a liking to our H2O can fill their bottles free of charge.

His argument is that if a charge was put on water a power company like Meridian for example, which drives its turbines through its hydro schemes, would end up passing the cost on to the consumer.

But the argument's spurious. The water through the turbine remains in this country for everyone's use, the water bottled and sent abroad, lines the pockets of those lucky enough to have been given a resource consent to access it. And it's a growing industry with more than seventy bottling plants currently operating in this country.

One company, with a sole Chinese shareholder, says it'll fill 32,000 bottles of water an hour and will operate 24 hours a day, seven days a week.

Another Chinese controlled company has seen its plans scuppered to extract 1.4 billion litres of artesian bore water every year under a 30-year resource consent which was granted without public consultation. A public outcry saw the Ashburton District Council pulling the plug on that plan.

The Government should think again, water being bottled for export should at least attract some sort of royalty. Just like oil or gold, it's a commodity.