The Six Basins Watermaster was formed by a stipulated agreement, the final Judgment becoming effective in January 1999. The Judgment establishes groundwater rights and provides a structure for the operation and management of the Six Basins, which are comprised of the Canyon, Upper and Lower Claremont Heights, Pomona, Live Oak, and Ganesha Basins. The Six Basins underlie the cities of Claremont, La Verne, and Pomona. The current Safe Yield is set at 24,000 acre-feet. It is reviewed and set on an annual basis.