River Level MCP

river-level-mcp

Live US river levels for AI assistants: river stage, streamflow and water temperature from USGS stream gauges, with NWS flood stages and river forecasts.

This is a Model Context Protocol (MCP) server. It reads the USGS Water Data API and the NOAA National Water Prediction Service at call time. It needs no API key.

Tools

Tool	What it returns
find_river_gauges	Active USGS river and stream gauges by river and place name, state, or latitude and longitude, with each gauge's latest stage and flow. Active gauges first.
get_river_level	Current river stage (gage height, ft), streamflow (discharge, ft3/s) and water temperature where measured, the measurement time, NWS flood stages, current flood category, feet below flood stage and record crest. Flags readings over 48 hours old.
get_river_history	Daily mean streamflow or stage for 2 to 366 days, with first, last, low, high, mean and change.
get_flood_forecast	The current NWS river forecast for a gauge: forecast series, forecast crest and its flood category, latest observation, flood stages and record crest.

Every result has structured JSON, a one-paragraph summary, as_of, source (the USGS or NWS gauge page) and more (a page on lakelevelnow.com).

What it knows that your model does not

• Today's river level. Gauges report every 5 to 60 minutes and a river can rise 10 feet in a day. A model's training data is months old.
• Whether a river is near flood stage right now, using the NWS action, minor, moderate and major flood stages for that gauge.
• The latest NWS river forecast and its crest, reissued several times a day.
• The new USGS Water Data API. The legacy waterservices.usgs.gov service shuts down on February 22, 2027, so code that calls it will stop working. This server already uses api.waterdata.usgs.gov.

Install

Hosted (Claude.ai custom connector, ChatGPT developer mode)

Paste this URL. No token, no sign-up.

https://river-level-mcp.lipmichal.workers.dev/mcp

Claude Code

claude mcp add --transport http river-level https://river-level-mcp.lipmichal.workers.dev/mcp

Or run it locally over stdio:

claude mcp add river-level -- npx -y github:theluckystrike/river-level-mcp

Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "river-level": { "command": "npx", "args": ["-y", "github:theluckystrike/river-level-mcp"] }
  }
}

Cursor

Add to ~/.cursor/mcp.json:

{
  "mcpServers": {
    "river-level": { "url": "https://river-level-mcp.lipmichal.workers.dev/mcp" }
  }
}

VS Code

Add to .vscode/mcp.json:

{
  "servers": {
    "river-level": { "type": "http", "url": "https://river-level-mcp.lipmichal.workers.dev/mcp" }
  }
}

Node 20 or newer is needed for the local stdio version.

Example prompts

• "What is the Mississippi River level at St. Louis right now?"
• "Is the Potomac at Little Falls near flood stage?"
• "How much water is flowing in the Colorado River at Austin, and how has it changed over the last 90 days?"
• "When will the river crest at EADM7, and will it reach flood stage?"
• "Which stream gauges are within 10 miles of 38.95, -77.13?"

Data sources

Full list with fetch dates in DATA_SOURCES.md.

• River stage, streamflow, water temperature, daily means and site details from the USGS Water Data API (OGC API collections latest-continuous, daily, monitoring-locations).
• Flood stages, record crests and river forecasts from the NOAA National Water Prediction Service API.
• The hosted server caches readings at the edge for a few minutes and site details for a day, so repeat calls do not reach USGS or NOAA.

Limitations

• USGS real-time data are provisional and can be revised. The tools say so.
• Only gauges that are NWS forecast points have flood stages and forecasts. Other gauges still return the USGS reading.
• NWS stage and USGS gage height normally use the same gauge datum, but check the NWS gauge page before relying on a threshold comparison for safety. Follow local NWS warnings for flood decisions.
• The USGS API applies a rate limit to keyless callers. When it answers 429 or is down, the tool returns a clear error instead of a stale or remembered number.
• Lakes and reservoirs are covered by lake-level-mcp.

More

Live lake and reservoir levels for Lake Mead, Lake Powell, Lake Travis and more are on lakelevelnow.com.

Part of the Zovo MCP collection: https://mcp.zovo.one

Development

npm install
npm test            # builds, then runs the fixture tests against saved USGS and NOAA payloads
node scripts/smoke-stdio.mjs   # live stdio check, one real call per tool
npx wrangler deploy            # Cloudflare Worker, Streamable HTTP at /mcp

License

MIT