Depletion of aquifers is a looming tragedy. New agreements offer hope

In his book _Cadillac Desert_, Marc Reisner points out that the aquifers in North America were laid down during the last Ice Age, and they will not be replenished until the next Ice Age. The western part of the US is doomed, therefore, and will collapse like other desert civilizations. He also points out that the Aswan dam has similarly doomed Egypt, since it disrupted the annual flooding of the River Nile.

Of course, some adjustments can be made. 80% of water use in California is for commodity agricultural production, meaning that this water can be diverted to supporting the coastal urban population without too much disruption to the world economy. So, California is not dehydrated yet.

Perhaps the best way to define aquifer shares is to predict the landmass collection contribution of the sharing states. This would mean that Egypt and lybia get nearly nothing of the Nubian field but rather Ethiopia and Sudan mostly the benefactors of the Nile bounty

Seems fair so Mexico gets almost nothing of the Colorado bounty but a fair share. Of the rio grande The nations in south America seem to have same kind of concept sorted out.

The world wide atlas on transboundary aquifers can be found on http://www.isarm.net/publications/322 . A discussion of the work done in compilong this was described in http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1105354
Aquifers contain 99% of the worlds freshwater that can be accessed for drinking, irrigation and municipal and industrial use. Yet hardly any expenditure is made by Governments to explore, manage and conserve this valuable water. It has been called a 'hidden treasure' as it is found underground - though most people will know about it if they have ever drawn water from a well ...its the wells - deep and shallow, that penetrate aquifers and allow humanity to use it for our well being. Almost 2.5 billion people on the planet totally rely on this water source.
Governments and investment agencies might think about deploying this water to meet the Millenium Development Goals on water. More information from the International Assocation of Hydrogeology www.iah.org

Shammy Puri
Secretary General, Internatoal Association of Hydrogeologists