One thing I like about this idea is that there doesn't seem to be the impact that, for example, a hydroelectric plant would have. In other words, because the streams are intermittent, and because most of the flow seems to be restored by overflow downstream, you don't interrupt things like migratory fish.

It's a neat concept. It gets the water beneath a thermal mass, stabilizing its temperature and preventing evaporation. The water can become available to deep-rooted plants and trees, too. I wish I'd thought of it!