While I am not a specialist on water suppy engineering, I find I am being increasingly drawn to it, both through my current work projects and through my charitable work.
There has been increasing talk of water scarcity, even to the point of speculating about resource wars over water. I have read a few article over the years on this, and here is one from the Guardian giving a good overview:
Also, a gallery of images accompanying the article.
Related is the website of the End Water Poverty campaign, which has some statistics and reports worth reading.