Dashboard · Drinking Water

Checking the Drinking Water API…

Free US drinking water data — every public water system and its current health-based violations — API + MCP, no key. Every US public water system in the EPA Safe Drinking Water Information System (SDWIS), in plain JSON for people and AI agents. Ask which systems serve a county, which ones have open health-based violations right now, or look up one system by its PWSID, and get plain JSON back. No key, no signup.

Look up a county

County names are as reported to SDWIS (the EPA spelling) and match case-insensitively. A county summary describes all systems serving that county — it is not a verdict on the water system at one address.

Look up one water system

Drinking Water tools

The same data, as MCP tools for AI agents — 6 tools at https://water.morningbrief.link/mcp.

The data

• Water systems: every US public water system in EPA SDWIS — 434,757 systems in the 2026 Q3 vintage, 143,024 of them active: community, non-transient non-community, and transient non-community systems.
• Health-based violations only: maximum contaminant level (MCL), treatment technique (TT), and maximum residual disinfectant level (MRDL) violations. Monitoring and reporting violations are not included.
• Current violations: violations with a current status of Unaddressed or Addressed — about 16,000 open across roughly 5,000 systems (live counts are in /v1/status).
• Summaries: county and state roll-ups — system counts, active counts, population served, and systems with current health-based violations.
• Refresh: quarterly, from EPA's ECHO bulk download of SDWIS.

What you can ask

• “Which water systems serve Cook County, Illinois, and how many have open health violations?”
• “Look up water system IL0970450.”
• “Which contaminants have current health-based violations, and how many systems do they affect?”
• “Summarize drinking water systems in Illinois, county by county.”
• “Show me current health-based violations in Texas.”

Good for local reporters, researchers, home buyers checking an area, and AI agents that need real drinking water data instead of guesses. SDWIS covers public water systems only — private wells are not in it — and states report to SDWIS on their own schedules, so very recent violations may be underreported.

Where the data comes from

All data comes from the EPA Safe Drinking Water Information System (SDWIS), via EPA's ECHO bulk download, 2026 Q3 vintage. EPA data only: if SDWIS doesn't publish it, Drinking Water doesn't invent it. The data vintage and last refresh are shown in /v1/status. Data refreshes quarterly.

County population figures sum the full population of each system serving the county; a system serving several counties counts in each one.

Use it with an AI agent (MCP)

Drinking Water is an MCP server with 6 tools. Point any MCP client at:

https://water.morningbrief.link/mcp

Claude / MCP client config:

{
  "mcpServers": {
    "drinking-water": {
      "url": "https://water.morningbrief.link/mcp"
    }
  }
}

ChatGPT and other clients can use the same URL as a remote MCP / connector endpoint. No key, no auth. The tools: get_water_system, search_water_systems, get_county_water_summary, get_state_water_summary, get_current_health_violations, list_contaminants_with_violations.

Use the REST API

Base URL: https://water.morningbrief.link. Counties take a state and a county name as reported to SDWIS (case-insensitive). Only health-based violations are included, and “current” means a status of Unaddressed or Addressed.

curl "https://water.morningbrief.link/v1/drinking-water/system?pwsid=IL0970450"   # one water system

curl "https://water.morningbrief.link/v1/drinking-water/search?state=IL&active=true&limit=5"   # active systems in Illinois

curl "https://water.morningbrief.link/v1/drinking-water/county?state=IL&county=Cook"   # Cook County, IL summary

curl "https://water.morningbrief.link/v1/drinking-water/state?state=IL"   # Illinois roll-up

curl "https://water.morningbrief.link/v1/drinking-water/violations?state=IL&limit=5"   # current health-based violations in Illinois

curl "https://water.morningbrief.link/v1/drinking-water/contaminants"   # contaminants with current violations

curl "https://water.morningbrief.link/v1/status"   # live status & dataset catalog

Full reference: API documentation · tools · live status & dataset catalog (JSON)

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