Water is a basic human need. Yet according to Unicef, 768 million people globally do not have access to a safe, clean source. While other organizations put that number higher (some say a billion people, or one in seven) all watchdog groups agree that water scarcity is a growing global problem. Designers David Turnbull and Jane Harrison of PITCHAfrica answer back with their Waterbank School. Lauded as the Greenest School on Earth by USGBC, the design recently received recognition and awards from the Buckminster Fuller Institute and Interface.