The United States Environmental Protection Agency (EPA) is responsible for establishing drinking water standards and regulations under the Safe Drinking Water Act (SDWA) for all public water systems (PWS) in the United States. In New Hampshire, these regulations are administered by the New Hampshire Department of Environmental Services’ (NHDES) Drinking Water and Groundwater Bureau (DWGB). Part of the SDWA requires the EPA to issue a list of unregulated contaminants that all PWS must monitor for through water sampling. This program is known as the Unregulated Contaminant Monitoring Rule (UCMR) Program. The results from the UCMR water sampling provide the EPA with information about the prevalence and amount of the unregulated contaminants detected in all PWS and assist EPA in determining future regulation requirements.

Details about the UCMR Program can be found here: https://www.epa.gov/dwucmr/learn-about-unregulated-contaminant-monitoring-rule

The current program is UCMR 5, which requires each PWS to sample for 30 chemical contaminants: 29 per- and polyfluoroalkyl substances (PFAS) and lithium between 2023 and 2025. Merrimack Village District (MVD) has completed the required UCMR 5 water sampling.

• Click HERE to view MVD's UCMR 5 Water Sampling Results

• The EPA’s report of complete UCMR occurrence data is available on the EPA’s website at: www.epa.gov/dwucmr/occurrence-data-unregulated-contaminant-monitoring-rule.
• Additional information about UCMR 5 can be found on the EPA’s website here: www.epa.gov/dwucmr/fifth-unregulated-contaminant-monitoring-rule