Treehugger: We’re well aware of the fact that humans have a significant impact on water supplies — from groundwater pumping to altering the course and flow of the world’s rivers, we are no small player in how much fresh water exists on the planet. However, would we ever have guessed that we were four times more significant than climate change on water supplies? A new report shows that we really need to focus far more on humans than warming temperatures if we want to avoid major water conflicts in the …