Your water is regularly tested for more than 120 chemicals and other substances, as well as radioactivity. Every year, we produce an Annual Water Quality Report, which lists the annual results for the chemicals and other substances detected in your water. The table below provides detailed information about the water that is delivered to your home or business after it is treated (treated water) and before it is treated (untreated water). The substances shown in this table are ones that our customers have the most questions about. Call our Water Quality Hotline with questions at 925-688-8156 or send us an email.
Also, the United States Environmental Protection Agency has additional contaminant list information about the fourth Unregulated Contaminant Monitoring Rule (UCMR 4). For general background information, see their UCMR Basic Information Fact Sheet (PDF).