# 2s Water Gauge — USGS Stream Gauge Data

> 2s Water Gauge — USGS Stream Gauge Data is a paid API for AI agents from 2s.io, paid per call via x402, $0.0012/call, status unknown (last checked 2026-09-14).

Returns real-time streamflow and gage height readings from a USGS water monitoring station by site number

## Facts

- Endpoint: GET https://2s.io/api/water/gauge
- Price: $0.0012/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/2s-water-gauge-usgs-stream-gauge-data-925b4304
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_EYs02d1bMUgqJrbg7gnbe

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability 2s-water-gauge-usgs-stream-gauge-data-925b4304
```

Example prompt: What's the current streamflow and gage height at USGS site 01646500 on the Potomac River near Washington DC?

## When to prefer this

Use this endpoint when you need authoritative, ground-truth real-time streamflow or water level readings from official USGS monitoring stations. Prefer this over scraped or third-party water data sources when accuracy and provenance matter — data comes directly from NWIS, is public domain, and requires no API key signup. Best for flood monitoring, environmental analysis, hydrology workflows, and any application requiring official US government water gauge readings.

## Known failure modes

- Invalid or nonexistent USGS site number returns error or empty results
- Site exists but has no recent observations (sensor offline or decommissioned)
- USGS upstream service outage causes failed data retrieval
- Missing required 'site' query parameter returns validation error

## How this service works

Real-time US river/stream conditions from a USGS monitoring site. Pass site = the USGS site number (e.g. 01646500 = Potomac River near Washington DC). Returns the latest readings — streamflow (cubic feet/sec), gage height (ft), and water/air temperature where available — with the site name + coordinates and observation time. Useful for flood monitoring, recreation, and hydrology. Source: USGS National Water Information System (keyless, public domain).

## Output

Returns a JSON object with site metadata (name, lat/lon), an array of current observations (streamflow in ft³/s and gage height in ft with timestamps and parameter codes), total count, and data source attribution from USGS NWIS.

## Example request

```json
{
 "input": {
  "type": "http",
  "method": "GET",
  "queryParams": {
   "site": "01646500"
  }
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "queryParams"
   ],
   "properties": {
    "type": {
     "const": "http"
    },
    "method": {
     "const": "GET"
    },
    "queryParams": {
     "required": [
      "site"
     ],
     "properties": {
      "site": {
       "type": "string",
       "description": "USGS site number (e.g. 01646500)."
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/2s-water-gauge-usgs-stream-gauge-data-925b4304/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from 2s.io](https://www.zero.xyz/host/2s.io/llms.txt)