Recently updated to version 1.1 see the release notes for details! →
Decoding Drinking Water with EPIC’s Drinking Water Explorer Tool
Explore Better Drinking Water Data Across the Nation
All Americans deserve access to safe, reliable, and affordable drinking water. But making that access into a national reality means untangling a complex web of interdependent factors—including crucial, but often fragmented, water data.
To address these issues, the Environmental Policy Innovation Center (EPIC) is launching a new web-based platform: the National Drinking Water Explorer - Dataset & Tool (Version 1.0). Covering the 44,000+ Community Water Systems across the nation, this data product harmonizes information across sources and scales—integrating nearly 30 state and national datasets and more than 100 variables—so policymakers, advocates, researchers, utilities, and communities can use drinking water data to improve environmental and public health outcomes.
Release Notes
Version 1.1
July 2026
Improved map and filtering performance with server-side caching.
Enhanced filtering experience with updated histograms and ability to enter min/max values.
Encoded URLs based on filter configuration.
Simplified map navigation experience and quick links to U.S. territories.
Revamped table; ability to manage columns, customize download selection, improved performance, and one click copy paste for water system ids!
Shareable and printable system level reports.
Improved documentation, and publicly accessible open source Github repository for the tool.
Countless small tweaks and bug fixes.
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Drinking water data is disconnected and difficult to use, presenting significant barriers to those looking to learn more, and ultimately work to improve quality, access, and affordability for all. EPIC built these resources as an accessible entry point for both the data curious and seasoned practitioner.
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The dataset and accompanying explorer tool help various audiences to learn more about public drinking water systems across the United States. Leveraging a data inventory spanning nearly 30 datasets and over 100 variables, the tool shows a growing collection of drinking water information from federal, state, and non-profit data sources. The tool enables people to filter and display various characteristics dependent on their priorities - at the water system level. Additional context is provided for people to learn more about the underlying data. The data can be downloaded for the entire nation, or a specific state.
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EPIC built this tool for people looking to learn more about community water systems in the United States. Our core audience is those looking to gain access to data and analytics about water systems across the nation - or in a particular geographic area –to inform research, technical assistance, policy making, regulatory activities, and utilities - all to improve drinking water delivery.
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If you have an immediate concern about your drinking water quality, please contact your local water system and/or public health department.
If you require authoritative data as a part of a regulatory reporting requirement, please use the original data source.
This dataset is not a replacement for supplanting information provided by a primary source, i.e. water system or utility, local health department, state or federal agency.
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While the EPIC team is working diligently to ensure the highest quality data and experience for people using the tool, there are undoubtedly ways it could improve. Please complete our feedback form to report something wrong with the data, or how it's displayed within the tool. If you’d like to share ways the tool could be improved, use our site improvement survey.
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All data has assumptions and caveats and different use cases will have different thresholds for uncertainty. EPIC has consolidated this information for each dataset within the tool (‘Datasets’ tab and our documentation). Don’t hesitate to reach out through our feedback form or contact us via email if you have any questions about how to use a particular dataset’s information.
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No, our data makes no claims of authority, nor is it explicitly endorsed by any government agencies. While the data we host is often collected directly from government sources, it's not to be understood as government owned. EPIC takes great care to display data with little to no manipulation. However we always recommend directly referencing the original data provider to ensure accuracy and recency.
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Yes! The data available in the tool will be updated on a quarterly basis, reflecting changes in various datasets. The dataset page indicates how frequently specific datasets are expected to be updated, and when they were last updated. While EPIC strives to maintain data recency inline with the original source, the tool can lag behind for some datasets. For example, some states like Oregon update their boil water data daily - meaning boil water data in EPIC’s tool can be up to 90 days behind the state resource.
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The U.S. EPA’s Water Infrastructure Capacity and Assessment Tool - this tool also uses EPA’s Water Service Area Boundary data, alongside compliance and detailed State Revolving Fund (SRF) data. EPIC recommends utilizing this tool if you require authoritative data, for example, when submitting a State Revolving Fund (SRF) application. The tool also includes data on wastewater systems.
Community Water Center’s Drinking Water Explorer Tool - this California focused tool contains data on private wells, aquifers, and Central Valley specific data such as Controlled Animal Feeding Operations and pesticide usage. EPIC recommends consulting this tool if you’re interested in California based information.
DigDeep and Michigan State’s Water Dashboard - this national scale tool is geared towards visualizing data at the state and county level. The tool contains data from the U.S. Census and EPA’s Safe Drinking Water Information System. Notably, this tool contains information about places that don’t have indoor plumbing.
In 2024, EPIC developed the Texas Water System Prioritization Tool, a precursor to this project. We no longer maintain the data for this tool, but it contains different features like bivariate mapping and reporting - currently not present in the National Drinking Explorer Tool.
Tap Truth reveals EPA Safe Drinking Water Information System (SDWIS) data in an easy address search format. It's built for general public interest in drinking water transparency. The application is powered by EPIC’s National Dataset, specifically utilizing simplified EPA SDWIS data and Service Area Boundaries.
Technical Resources and More on This Tool
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EPIC’s documentation provides people with a host of methodological considerations and assumptions made during development of the tool. Our data dictionary includes a summary of datasets, variables, vintage, and descriptions for data in the tool and downloads.
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EPIC’s Github data collection repository contains code for downloading, organizing, and analyzing data for this project. Data organized from this repository are used in the tool. Check out the project board to see our development!
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EPIC’s Github tool repository contains the code for creating the web application tool. Check out the project board to see our development!
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EPIC’s feedback survey is a way for people to tell us where they think improvements need to be made to this tool. We plan to do multiple rounds of updates in the coming months ahead and deeply appreciate people taking the time to fill out this short survey.
Do you have questions, comments, or concerns with the data or features in this tool? Interested in learning more about, or supporting, this work? EPIC wants to hear from you!
EPIC gratefully acknowledges the support of our philanthropic partners for this work - Duke University, Stanford University, Mitchell Foundation, Temple Foundation, Wellspring Foundation, Aqualateral, and McGovern Foundation.