EPA updated its publicly available database of analytical results and prepared a summary of results received as of Oct. 2 for the Fourth Unregulated Contaminant Monitoring Rule (UCMR 4). UCMR 4 mandates all large public water systems serving more than 10,000 people and 1,600 small public water systems in the United States monitor for 30 selected contaminants (metals, cyanotoxins, pesticides, brominated disinfection byproducts, alcohols and semi-volatile organic chemicals). Testing started in January 2018 and will conclude in December 2020. EPA uses the UCMR to inform regulatory decision-makin g under the Safe Drinking Water Act. The purpose of UCMR is to collect data to understand the nationwide occurrence of contaminants that may be in drinking water but are not regulated. EPA will continue to update UCMR 4 data approximately quarterly. Reported data is subject to change until a final dataset is published in early 2022, when UCMR 4 testing and quality assurance/quality control is complete. AWWA recommends members review the posted data and consider posting local results on their websites to demonstrate transparency, explain the purpose of UCMR and properly characterize results. In responding to inquiries, AWWA recommends that utilities: Acknowledge the concern all contaminants present to safe drinking water. Emphasize to media and consumers that you are committed to protecting public health. Point out that your utility also seeks out and monitors for unregulated contaminants under UCMR to stay ahead of potential health risks. Make clear that your water meets federal and state standards for safety (clearly explaining any SDWA violations). Focus on how water risks are assessed and managed, using the rigorous scientific framework of the Safe Drinking Water Act (SDWA) and your state (equivalents). Invite media and consumers to learn more about your local water quality by providing them with consumer confidence reports and other web-based information or connecting them to the appropriate utility contact. If possible, contact your local health department and/or a trusted academic voice to collaborate on a response. Water systems must distribute their consumer confidence reports (water quality reports) to customers by July 1. The CCR must include: An explanation of unregulated contaminants and their presence in drinking water, if detected, and A table summarizing data on detected regulated and unregulated contaminants. AWWA has updated the “ What’s In My Water? ” section on DrinkTap.org to include several contaminants that are included in UCMR 4 monitoring. Haloacetic acids and manganese are by far the most frequently observed contaminants in the UCMR4 data to-date. While the current data does not include many algal toxin observations, please see prior AWWA alerts with respect to planning for public communication in anticipation of this year’s UCMR cyanotoxin monitoring. The UCMR webpage on DrinkTap has also been updated to reflect information that pertains to UCMR 4 specifically. Questions can be directed to Steve Via , AWWA director of federal relations or Greg Kail , AWWA communications director.