Basically DRI seeds the clouds on the west coast, especially during the winter so it snows heavy in Colorado. Snow melts into the Colorado River giving water to Las Vegas, Arizona and Southern California
Super crazy ass shit on this site but it's all out in the open. They have a Microbial Ecology Laboratories. -- Taken from Wiki regarding Microbial Ecology -- It concerns the three major domains of life — Eukaryota, Archaea, and Bacteria — as well as viruses