THE Benjamin Franklin quote on Summit Global Water Management's website says it all: "When the well's dry, we know the worth of water."

US directors of Summit Global management know Melbourne's and Adelaide's wells are running dry.

They have first-hand experience of what happened to the price of water when California's urban thirst for water drained rural communities.

Global Summit's strategy states: "Combined with the vigorous demand and climate-related market drivers that are now becoming globally and undeniably apparent, hydrocommerce presents a very compelling investment theme for the predictable future."

Summit directors and managers are out to make a buck for their investors and believe water is gold in the face of climate change and booming urban demand.

But as Summit Global's Matt Dickerson said there are "few areas where we can execute our strategy, but Australia is one of them".

Australia's water markets are relatively advanced compared to the rest of the world. Anyone can now buy and trade water.

The Victorian Government imposed a few restrictions on corporate players, such as the 10 per cent limit on the volume of entitlement held within a system by non-water users.

However, this cap has not been reached and can easily be avoided.

Any other limitations on buying and accumulating water can easily be circumvented by parking temporary water on other irrigators' entitlements in Victoria or interstate.

The big question for irrigators and urban communities is how do they deal with a new player in the water market.

Some irrigators will no doubt see it as a threat. Others may see it simply as another player in the market.

The facts are corporate managed investment scheme operators, such as Timbercorp, already own huge parcels of water. Just because the directors behind the latest purchasing bid happen to be from the US doesn't mean much.

The real question for government is what restrictions, if any, should we place on the ownership of our nation's scarcest resource?

What's the risk of the market being controlled by corporate investors?

Could we one day see South Australian or Victorian governments in court battling to regain control of water from corporate investors?

At this stage there is no debate on these issues.