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Providing accurate, accessible water quality information for every American community. We translate official EPA data into clear, actionable information so you can make informed decisions about your drinking water.
Clean drinking water is fundamental to public health, yet understanding what is in your tap water can be surprisingly difficult. Water utilities publish annual Consumer Confidence Reports filled with technical terms and data tables that many people find overwhelming. The EPA maintains comprehensive databases of water quality testing and violation records, but accessing and interpreting this information requires specialized knowledge.
US Water Grade exists to solve this problem. Our mission is to make official EPA water quality data accessible, understandable, and actionable for every American household. We believe that every person deserves to know what contaminants have been detected in their local water supply, how those levels compare to federal safety standards, and what steps they can take if they have concerns.
We translate complex water quality data into clear grades and straightforward recommendations. Our goal is not to cause alarm, but to provide the information you need to make informed decisions about water filtration, testing, and consumption for your family.
US Water Grade is an independent informational resource operated by a small team of data analysts, researchers, and web developers passionate about environmental health and public information transparency. We are based in the United States and are committed to making water quality data accessible to everyday Americans.
We are not affiliated with the EPA, any water utility, water filter manufacturer, or testing laboratory. We do not receive government funding and are not a government contractor. Our independence ensures that our analysis and recommendations are based solely on the data, without commercial influence.
This website is supported by advertising revenue and affiliate partnerships with water filtration companies. However, our water quality scores and data presentation are never influenced by these relationships. We clearly disclose affiliate relationships and only recommend products that are independently certified for the contaminants they claim to remove.
We do not conduct our own water testing or operate water quality laboratories. All water quality data on US Water Grade comes from official government sources maintained by the U.S. Environmental Protection Agency:
Our primary data source. SDWIS is the official federal database containing water quality testing results, violation records, and compliance data for all 148,000+ public water systems serving Americans. The database is maintained by the EPA Office of Ground Water and Drinking Water.
SDWIS contains data on: contaminant testing results and maximum contaminant level (MCL) compliance, health-based and monitoring violations, enforcement actions and return to compliance status, system inventory and population served, and source water information.
Learn more about SDWIS →ECHO provides detailed compliance and enforcement data for water systems, including formal enforcement actions, significant non-compliance status, and inspection history. We use this data to assess the regulatory track record of water systems.
Visit EPA ECHO →Water utilities serving more than 15 connections are required by law to provide annual Consumer Confidence Reports to their customers. These reports detail all contaminants detected in the water supply and their concentrations relative to EPA limits. We cross-reference CCR data with SDWIS to provide comprehensive water quality profiles.
Learn about CCRs →Health information and contaminant guidance on our site is based on EPA Maximum Contaminant Levels (MCLs), EPA Maximum Contaminant Level Goals (MCLGs), and health risk assessments published by the EPA, CDC, and peer-reviewed scientific literature. We clearly cite sources for all health-related information.
We retrieve water quality data from EPA databases through official APIs and data downloads. Our data pipeline processes this information and organizes it by geographic location to create city and state pages. We do not modify contaminant readings or violation records from the source data.
Our scoring methodology converts raw EPA data into understandable grades using a transparent, reproducible process. We designed this system to provide a quick, at-a-glance assessment while encouraging users to review the detailed contaminant data:
Our letter grades provide an intuitive summary of water quality. However, we encourage all users to review the detailed contaminant data, as individual contaminants may be of particular concern based on personal health circumstances.
If you notice outdated or incorrect information, please contact us immediately.
Understand what contaminants are in your tap water and whether additional filtration may be beneficial for your household.
Make informed decisions about water safety for children, who may be more sensitive to certain contaminants than adults.
Individuals with compromised immune systems or specific health concerns can research water quality before making filtration decisions.
Research water quality in potential new neighborhoods before relocating, or understand water quality when arriving in a new city.
Access water quality data for research, advocacy, and community organizing around clean water issues.
Access organized water quality data for stories, reports, and academic research on drinking water safety.
US Water Grade is a free resource supported by affiliate partnerships. When we recommend water filters or testing kits, some links may be affiliate links, meaning we earn a small commission if you make a purchase at no additional cost to you.
Our recommendations are based on contaminant profiles and filter certifications, not affiliate relationships. We only recommend products that are NSF/ANSI certified for the specific contaminants they claim to remove.
While we strive to provide accurate and helpful water quality information, there are important limitations to understand:
For these reasons, we recommend home water testing if you have specific concerns, especially if you have older plumbing, live in a pre-1986 building (when lead plumbing was common), or are in a vulnerable population. Certified laboratories can test your tap water for contaminants of concern.
Have questions about our methodology, found an error in our data, or want to provide feedback? We'd love to hear from you.
Contact Us →This website is for informational purposes only and is not health advice.
The information provided on US Water Grade is intended to help you understand publicly available water quality data. It should not be used as a substitute for professional medical advice, diagnosis, or treatment.
Contact your local water utility for official water quality information and concerns.Your water utility is the authoritative source for information about your specific water supply. You can request a copy of your annual Consumer Confidence Report (CCR) directly from them.
If you have health concerns related to your water quality, please consult with a healthcare provider. Vulnerable populations including pregnant women, infants, elderly individuals, and those with compromised immune systems should take extra precautions and seek medical guidance.