Query public USGS water observations for stream gauges and watershed research. This is separate from earthquake data and focuses on streamflow and gauge discovery.

Tools

get_streamflow: instantaneous observations for a gauge and USGS parameter code. 00060 is the common discharge parameter.
find_gauges: find active stream gauges in a min longitude,min latitude,max longitude,max latitude bounding box, with a bounded result count.

The server uses USGS Water Services without an API key. Data can be provisional and may be revised by USGS. Requests time out after 20 seconds.

Run

npm install
npm run build
node dist/index.js

Read-only stdio MCP server. No credentials or local source data are required.

Quick start

npm install
npm run build
node dist/index.js

The server uses stdio, so it can be connected to Claude Desktop, Cursor, VS Code, MCP Inspector, or another compatible MCP client.

Tools at a glance

get_streamflow: Get USGS instantaneous water observations for one gauge.
find_gauges: Find active USGS stream gauges in a longitude,latitude bounding box.

Limits and privacy

This project is intentionally narrow. It should be treated as a practical helper, not a complete certification or security audit. Check the implementation and the returned data before using it with sensitive material. No credentials are required unless the project explicitly says otherwise.

Try it

After building, connect the server through your MCP client. The repository root also contains smoke-test.mjs for projects covered by the shared harness. A typical tool call starts with get_streamflow.

Premium tools

These tools need a license key:

daily_values

Buy a key at https://mcp-marketplace.io/server/io-github-mrfentmen-usgs-water-mcp and set it in your MCP client config:

"env": { "MCP_LICENSE_KEY": "mcp_live_..." }

The key is checked against MCP Marketplace, cached for 24 hours, and keeps working offline once one check has succeeded. Every other tool on this server stays free.