I think that most of us have sat near a stream or pond and felt the positive effects. A waterfall not only oxygenates and cleans the water it also produces ions which have been shown to improve our mental state and outlook. Like a fire, running water is mesmerising and you can find your self transported to that same primordial place by a natural stream or waterfall. During drought times and really any time in parts of Australia I have been told by some that why would people want a pond due to water shortages. In my experience and through quite observation I have found that the less water there is the more people want to be around it. Its a basic instinct that all life on this planet including humans will always want to be near water and will create oasis’s to enjoy and to use. Its just important to design and build them to be efficient as possible. Build them well.