On August 27, the U.S. Environmental Protection Agency released the final set of national drinking water data collected under the fifth Unregulated Contaminant Monitoring Rule (UCMR 5) for 30 chemical contaminants: 29 PFAS plus lithium. The data collected under UCMR 5 improves understanding of the prevalence and amount of 29 PFAS and lithium in the nation’s drinking water systems.

With this data release, the EPA is now reporting all results that the agency received for UCMR 5 monitoring including just under 2 million results from over 10,000 public water systems nationwide. Based on the UCMR 5 data, the EPA estimates that 7.8% of water systems would have a running annual average above the Maximum Contaminant Level for PFOS or PFOA. There are no significant changes in the overall trends on occurrence for the 29 PFAS plus lithium at public water systems for this dataset from the previous interim releases.

The EPA will be updating results in the UCMR 5 Data Summary, UCMR 5 Data Finder, and Occurrence Data Files. This data collection effort will help inform EPA’s new PFAS OUT initiative to enhance engagement with water utilities and share resources, tools, funding, and technical assistance to help utilities address PFAS in drinking water. Services offered to utilities include water quality testing, development of technical plans, operator training support, designing public engagement and outreach strategies, and support for accessing federal funding opportunities.

UCMR 5 final data release includes:

  • UCMR 5 Data Finder – Allows the public, along with federal, state, and local agencies, to easily locate, view, and summarize specific UCMR 5 results, as well as download those results to an Excel (.xlsx) spreadsheet. Results can be filtered by multiple fields. A video demo is available. Please use this tool for accessing the publicly available results.
  • Occurrence Data Text Files – Recommended for those interested in large-scale data processing using statistical or data analysis software. These files contain analytical results and the additional data element and ZIP Code information reported by participating public water systems.
  • UCMR 5 Data Summary – National summary statistics by contaminant, health effects information, data considerations, and data definitions for the UCMR 5 Data Finder and Occurrence Data Text Files.
  • UCMR 5 Q&A – Answers to common questions on accessing and understanding the UCMR 5 data.