If you want to get a great download of data on water trends and challenges, it's worth spending a few minutes watching Prof. Hermanowicz's presentation here. And if you want to understand why it's a bit misguided to say that cleantech as a whole is unattractive in a low oil price environment, see the below oldie-but-a-goodie chart.  And notice how little oil goes into any energy consumption outside of transportation.  (It's also always fun to note how much "Lost energy" there is in the system)  Yes, there are linkages to pricing throughout the system, but despite what the TV may tell you, oil isn't the only price-setter in the energy world.