gov.usgs-water

Real-time water data from USGS NWIS stream / river / groundwater gauges within a bounding box around lat/lon. Returns each site's latest reading per requested variable: streamflow (00060, ft³/s), gage height (00065, ft), water temperature (00010, °C), precipitation (00045, in), and others. Each reading: site code + name, lat/lon, variable name + description + unit, value (or null if no data / sentinel), qualifier codes (e.g., 'P' = provisional, 'A' = approved), observed timestamp. Free public-domain data from waterservices.usgs.gov.

price

$0.0024 USDC per call

method

GET/api/gov/usgs-water

payment

x402 v2 · USDC on Base (EIP-3009) or Solana (SPL transfer)

auth

None. Sign the payment, retry with PAYMENT-SIGNATURE.

tier

Tier 0 — no paid upstream

Parameters

Name	Type	Description
`lat`required	number	Center latitude (decimal degrees). min -90 · max 90
`lon`required	number	Center longitude (decimal degrees). min -180 · max 180
`radius`	number	Half-side of bounding box, in decimal degrees. Default 0.5 (~35 mi). min 0.05 · max 2
`variables`	string	Comma-separated USGS parameter codes (5-digit). Default "00060,00065,00010" (streamflow, gage height, water temp). match ^(\d{5})(,\d{5})*$
`limit`	integer	Max readings to return (1-100). Default 25. min 1 · max 100

Code samples

cURLbash

# 1. Probe with no auth → 402 envelope with PaymentRequirements
curl -sS 'https://2s.io/api/gov/usgs-water?lat=-90&lon=-180&radius=0.5&variables=example&limit=25'

# 2. Sign + retry with PAYMENT-SIGNATURE:
curl -sS 'https://2s.io/api/gov/usgs-water?lat=-90&lon=-180&radius=0.5&variables=example&limit=25' \
  -H 'PAYMENT-SIGNATURE: <base64-json-payload>'

# Or use the canonical runner (handles probe → sign → retry):
#   EVM_PRIVATE_KEY=0x... node --env-file=.env.local \
#     --experimental-strip-types scripts/x402-pay.ts \
#     'https://2s.io/api/gov/usgs-water?lat=-90&lon=-180&radius=0.5&variables=example&limit=25'

TypeScript / Node — @2sio/sdktypescript

import { TwoS } from '@2sio/sdk'

const client = new TwoS({
  privateKey: process.env.EVM_PRIVATE_KEY as `0x${string}`,
})

const result = await client.gov.usgsWater({
  "lat": -90,
  "lon": -180,
  "radius": 0.5,
  "variables": "example",
  "limit": 25
})

console.log('endpoint:', result.endpoint)
console.log('cost:', result.costUsd, 'USDC')
console.log('tx:', result.settlement?.txHash)
console.log('data:', result.data)

Python — 2siopython

import os
from twosio import TwoS

client = TwoS(private_key=os.environ["EVM_PRIVATE_KEY"])

result = client.gov.usgs_water(lat=-90, lon=-180, radius=0.5, variables="example", limit=25)

print("endpoint:", result.endpoint)
print("cost:", result.cost_usd, "USDC")
print("tx:", (result.settlement or {}).get("tx_hash"))
print("data:", result.data)

MCP — Claude Desktop / AgentKit / any MCP hostjson

// 1. Add @2sio/mcp to your MCP host config (Claude Desktop example below).
//    EVM_PRIVATE_KEY funds x402 payments per call.

// claude_desktop_config.json
{
  "mcpServers": {
    "2sio": {
      "command": "npx",
      "args": ["-y", "@2sio/mcp"],
      "env": { "EVM_PRIVATE_KEY": "0x..." }
    }
  }
}

// 2. Once the server is running, agents call this tool via standard MCP:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "gov.usgs-water",
    "arguments": {
      "lat": -90,
      "lon": -180,
      "radius": 0.5,
      "variables": "example",
      "limit": 25
    }
  }
}

Response

Field	Type	Description
`query`	object
`bbox`	object
`returned`	integer
`readings`	array
`source`	object

Example response datajson

{
  "query": {
    "lat": 1,
    "lon": 1,
    "radiusDegrees": 1,
    "variables": [
      "example"
    ],
    "limit": 1
  },
  "bbox": {
    "west": 1,
    "south": 1,
    "east": 1,
    "north": 1
  },
  "returned": 1,
  "readings": [
    {
      "siteCode": "example",
      "siteName": "example",
      "agencyCode": "example",
      "latitude": 1,
      "longitude": 1,
      "variableCode": "example",
      "variableName": "example",
      "variableDescription": "example",
      "unit": "example",
      "value": 1,
      "qualifiers": [
        "example"
      ],
      "observedAt": "example",
      "noDataValue": 1
    }
  ],
  "source": {
    "provider": "example",
    "url": "https://example.com",
    "license": "example"
  }
}

Discovery

/api/directory — full catalog of every endpoint
/openapi.json — OpenAPI 3.1 spec (per-op x-payment-info, x402Payment security)
/.well-known/x402 — machine-readable service descriptor for x402-aware crawlers
/.well-known/mcp/server-card.json — MCP SEP-1649 server card
/llms.txt — plain-text manifest for LLM ingestion

2s.io is x402-native. Every call is paid per-request from a USDC-funded EVM wallet on Base — no signup, no API keys, no monthly fees. Source code: github.com/2s-io/sdk.