Official MCP RegistryListed
Drinking Water — EPA SDWIS: Water Systems & Health-Based Violations
EPA drinking water data: 434,757 public water systems, current health-based violations. No key.
First seen 1 Nov 2026. Evidence as of 1 Nov 2026.
6
Tools
From an anonymous probe
1
Source listings
Each with its own history
1
Recorded changes
Since first seen
Tools
| Tool | Description | Behaviour |
|---|---|---|
| get_county_water_summary | Summarize public water systems serving a US county: how many systems (and how many active), total population served, how many systems have current health-based violations and how many such violations are open, plus the worst-affected systems in the county. County names are as reported to SDWIS (uppercase). A county summary covers every system serving any part of the county; it is not a verdict on the water system at a specific address. | Read-only |
| get_current_health_violations | List current (unresolved) health-based drinking water violations from EPA SDWIS: maximum contaminant level (MCL), maximum residual disinfectant level (MRDL), and treatment-technique violations whose status is Unaddressed or Addressed. Monitoring and reporting violations are excluded. Filter by state, by PWSID, or by contaminant code; most recent compliance periods first. | Read-only |
| get_state_water_summary | Summarize public water systems for a whole US state: system counts, population served, systems with current health-based violations, and the counties with the most affected systems. Data is EPA SDWIS. | Read-only |
| get_water_system | Look up one US public water system by its PWSID (e.g. IL0970450). Returns the system's identity, type (community, transient, non-transient non-community), population served, service connections, owner and source type, the counties it serves, and its current health-based violations (unresolved MCL, MRDL, and treatment-technique violations) from EPA SDWIS. | Read-only |
| list_contaminants_with_violations | List every contaminant that has at least one current health-based violation in EPA SDWIS, with the number of open violations and the number of water systems affected, most violations first. Useful for seeing which contaminants drive current US drinking water violations. | Read-only |
| search_water_systems | Search US public water systems by name, and optionally narrow by state (two-letter code), county name as reported to SDWIS (requires state), system type code (CWS, NTNCWS, TNCWS), or active systems only. Results are ordered by population served, largest first, and each result includes its count of current health-based violations. | Read-only |
Change history
- Listed (registry)
| Source | Listing | First seen | Last seen | Versions |
|---|---|---|---|---|
| Official MCP Registry | link.morningbrief/drinking-water | 1 Nov 2026 | 1 Nov 2026 | 1 |