The Six Basins are located in the Eastern Los Angeles County and Western San Bernardino County, bounded on the south by the San Jose Hills, on the north by the San Gabriel Mountains, on the east by the Chino Basin and on the west by the Main San Gabriel Basin.
The Six Basins are comprised of the Canyon, Upper and Lower Claremont Heights, Pomona, Live Oak and Ganesha Basins. These six basins underlie the cities of Claremont, La Verne, Pomona and Northern Upland.
The members of Six Basins Watermaster are as follows:
• City of La Verne
• City of Pomona
• City of Claremont
• San Antonio Water Co.
• Pomona College
• Pomona Valley Protective Association (PVPA)
• Southern California Water Co. (SCWC)
• Three Valleys Municipal Water District
• City of Upland