Assessments of Public Water Supplies

To view completed source water assessments for small public water systems, visit the RI Department of Health’s website or call 401-222-5960 and ask for the public well program. For assessments of non-community public water systems, contact the RI Department of Health  at 401-222-5960 and ask for the public well program.

For guidance for community water suppliers on updating water supply system management plans, refer to the Guide to Updating Source Water Assessments and Protection Plans (Version 3).

About Source Water Assessments

The Safe Drinking Water Act (SDWA) Amendments of 1996 require states to develop and implement source water assessment programs (SWAPs) to analyze existing and potential threats to the water quality of the public drinking water throughout the state. Beginning in 2003, the RI Department of Health and NEMO completed assessments of all major community water supplies. With funding from the CDC, they began updating the assessments in 2021. A source water assessment is a study and report, unique to a water system, that provides basic information about the water used to provide drinking water. Land use, existing pollution sources, and water quality results are used to assess the water in the source water protection area, or the critical area surrounding a public water supply well or an intake on a surface source. Streams, lakes, and interconnected underground aquifers all contribute to recharging source water.

Visual abstract of a source water assessment; text explaining the components of a source water assessment

In many cases, the water service area is not the same as the source water area. Looking for areas with high intensity land use, such as densely developed or industrialized areas, can offer insight on potential pollution risks. Examining existing sources of pollution, such as stormwater outfalls or underground storage tanks, also provides valuable information on threats to source water quality.

Common Pollutants of Concern Detected in Source Water Assessments

Bacteria, nitrates, and PFAS are common pollutants detected in routine water quality testing. While they can pose a threat to drinking water sources, there are approachable actions community members can take to reduce the risk of exposure.

Understanding Risks

Source water assessments are a great tool to plan for improved protection of public drinking water sources. They outline risks as opposed to reporting confirmed drinking water contamination. However, they are a good starting place for planning water protection programs. Communities should act now to protect valuable water supply resources.