Water supplies in many countries all over the world are likely to dwindle in coming years due to a number of factors. Check out some of these past articles:
Pollution Disrupting Earth\'s Water Supply
War Over Water The real water supply problem exists in Australia, where it is projected that major cities like Perth and Sydney have somewhere between 1-5 years supply of water left (depending on how the situation is handled). Because of this, Australia will no doubt be at the forefront of new technologies aimed at curtailing the problem.
Australian Drought Towns Run Out of Water Running out of water - and time CSIRO Water, Water Everywhere... Jared Diamonds book
Collapse also covers this bleak topic pretty comprehensively.
Maybe we need to harness one of these babies...
Orion\'s Water Factory