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The Safe Drinking Water Information System (SDWIS) Modernization Program consists of a series of projects designed to deliver new system capabilities supporting U.S. EPA’s Public Water System Supervision program. The SDWIS Prime application is the second phase of SDWIS modernization. SDWIS Prime will be a centralized system, improving information exchange among primacy agencies, regulated entities, EPA Regions, and EPA Headquarters. SDWIS Prime will improve state decision-making by providing more efficient business process support and using a Business Rules Engine to determine compliance with drinking water rules based on sample data received from the Compliance Monitoring Data Portal (CMDP) and other sources.


Once implemented nationwide, SDWIS Modernization is expected to reduce state data management work – the time spent manually entering data, identifying data-entry errors, and issuing data resubmittal requests – by hundreds of thousands of hours per year. This will allow states and tribes to free up time to focus on preventing and responding to public health issues in their communities. Together, CMDP and SDWIS Prime also will help enhance the timeliness and accuracy of drinking water data transferred between drinking water systems, primacy agencies, and EPA. Systems like these can help move our country closer to a future where all Americans will have faster and better access to information about the quality of the water piped into their homes.


Phase 1 of the SDWIS Modernization Program, CMDP, allows water laboratories and public drinking water systems to electronically share drinking water data with their states and tribal agencies. The portal replaces a paper-based system, leading to more timely and higher quality monitoring data. For Phase 2 of SDWIS modernization, v0.8 was released early in 2018 for optional primacy agency testing of SDWIS Prime capabilities completed to date, with 40 primacy agencies testing SDWIS Prime over a seven-week period.



SDWIS Fact Sheet