In every case where large scale fast-growth tree monocultures are established water resources either diminish substantially or disappear entirely, mainly due to the high water intake of fast-growth alien tree species. Wells, wetlands, streams and even rivers dry up. The local affected communities give testimony of that.
WRM has produced a power point presentation -“Tree plantations and depletion of water resources” [http://www.wrm.org.uy/plantations/Tree_plantations_and_water.pdf] - which is a compilation of testimonies from people all around the world, providing more than sufficient evidence about the direct relationship between plantation expansion and depletion of water resources.
For us, they are the true experts from whom we can all learn.