Water Quality

Clean Water. In Southern California, for Southern California.




The vast watershed surrounding Cadiz has very few overlying land-uses and is free from the threat of bacterial waste and industrial contamination. Cadiz groundwater meets all state and federal drinking water standards without treatment.


The quality of Cadiz’s water is continually monitored by San Bernardino County as part of the company’s ongoing agricultural operations.


Total dissolved solids (TDS), a key measurement for determining water quality, typically ranges from 300 to 400 parts per million at Cadiz, significantly lower than California’s Colorado River supply, which can be as high as 800 parts per million in drier years. Models by the U.S. Bureau of Reclamation estimate that introducing Cadiz’s low TDS water into the Colorado River Aqueduct would reduce the need for treatment, saving ratepayers $400 million over the 50-year life of the Project.


There are constituents in Cadiz groundwater that have measured higher than California’s Colorado River supply, although they are still below drinking water standards. In order to provide further benefits to the Colorado River Supply, Cadiz and its participating agencies have committed to treat Project supplies prior to entering the aqueduct to meet or beat the levels of all constituents already in the supply, not just state and federal drinking water standards.




Cadiz has partnered with ATEC Systems Associates Inc., a water treatment technology firm, to treat Project groundwater for naturally occurring metals before the supplies enter the Colorado River Aqueduct. For example, levels of chromium-six and arsenic are below and comply with safe drinking water standards but are higher than those measured in the aqueduct.


The ATEC system being implemented at Cadiz will use a pressure filter operation known as Reduction-Coagulation-Filtration (RCF), which is listed as a best available treatment for hexavalent chromium removal by the California Division of Drinking Water (DDW). The ATEC process changes chromium-6 to chromium-3, a beneficial mineral found in daily multivitamins, and can remove arsenic during processing.


Pilot testing demonstrates that the ATEC technology can cost-effectively remove both chromium and arsenic at Cadiz. Water delivered from Cadiz will be clean and safe and will improve the quality of supplies in Southern California.


To download a Fact Sheet about Cadiz Water Quality, click here.

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