Western Water Datahub EDR with raw HTTP

1. Base URL and response formats

The base URL is:

https://api.wwdh.internetofwater.app

Most examples use f=json because WWDH is a pygeoapi service and serves collection metadata, GeoJSON, and CoverageJSON through JSON responses.

GET https://api.wwdh.internetofwater.app/collections?f=json

You can often request a browser-readable HTML page with f=html:

GET https://api.wwdh.internetofwater.app/collections?f=html

For command-line use, quote URLs that contain ?, &, parentheses, or spaces:

curl -sS 'https://api.wwdh.internetofwater.app/collections?f=json'

Useful f values:

For EDR data queries, prefer f=json. The body will usually identify itself as either GeoJSON ("type": "FeatureCollection") or CoverageJSON ("type": "Coverage" or "type": "CoverageCollection").

2. Discovery first

Start by asking what the service provides.

GET /?f=json HTTP/1.1
Host: api.wwdh.internetofwater.app
Accept: application/json

Equivalent full URL:

https://api.wwdh.internetofwater.app/?f=json

Then list collections:

GET /collections?f=json HTTP/1.1
Host: api.wwdh.internetofwater.app
Accept: application/json

Equivalent curl:

curl -sS 'https://api.wwdh.internetofwater.app/collections?f=json'

The response has a top-level collections array. Each collection has an id, title, extent, links, and sometimes a data_queries object.

The same document may also have a top-level parameterGroups array. Use parameterGroups when you want to translate a water-data concept across collections. For example, the Lake/Reservoir Storage group currently maps USBR RISE parameter 3 to USACE storage parameters such as Flood Storage and Conservation Storage.

As of June 4, 2026, examples include:

Inspect one collection before asking for data:

curl -sS 'https://api.wwdh.internetofwater.app/collections/snotel-edr?f=json'

Look for:

• parameter_names: data variables you can request with parameter-name.
• parameterGroups: cross-collection concept groups, when present.
• data_queries: supported EDR query types for that collection.
• links: HTML pages, JSON pages, /items, /queryables, and source documentation links.
• extent: the rough spatial and temporal coverage.

3. Endpoint map

These are the routes you will use most often.

Do not assume every collection supports every route. The collection document tells you what is advertised. A route that is valid for one collection may return 404 or 500 for another.

4. Common query parameters

Coordinates are longitude, latitude. A bbox is always:

min_lon,min_lat,max_lon,max_lat

Multiple parameters are comma-separated:

parameter-name=ppt,tmx

Some parameter ids contain spaces. Encode them in a hand-built URL:

parameter-name=Flood%20Storage

or let curl encode them:

curl -sS -G 'https://api.wwdh.internetofwater.app/collections/usace-edr/locations/157145' \
  --data-urlencode 'f=json' \
  --data-urlencode 'datetime=2024-01-01/2024-12-31' \
  --data-urlencode 'parameter-name=Flood Storage'

Intervals use a slash:

datetime=2024-01-01/2024-03-31

Open intervals may be supported by some providers:

datetime=2024-01-01/..

5. URL encoding rules

HTTP URLs cannot contain every character literally. Encode reserved characters in query values.

For WKT point coordinates, encode the space between lon and lat as %20:

coords=POINT(-112.4%2036.9)

A polygon must be URL-encoded if it contains spaces or parentheses. This readable WKT:

POLYGON((-106 39,-105.8 39,-105.8 39.2,-106 39.2,-106 39))

becomes a query value like:

coords=POLYGON((-106%2039,-105.8%2039,-105.8%2039.2,-106%2039.2,-106%2039))

Most HTTP clients can encode query parameters for you. If you build URLs by hand, be especially careful with spaces, #, &, +, and literal slashes inside path ids.

6. Finding parameters

Collection metadata is where EDR data variables live.

curl -sS 'https://api.wwdh.internetofwater.app/collections/usgs-prism?f=json'

In the response, inspect parameter_names.

Example usgs-prism parameter ids:

Example snotel-edr parameter ids:

Example reservoir/stage parameter ids:

Use the exact parameter_names keys in the URL. Labels are for humans; keys are for requests.

For cross-collection work, use the top-level parameterGroups block from /collections?f=json to find conceptually equivalent parameters. For example:

curl -sS 'https://api.wwdh.internetofwater.app/collections?f=json' |
  jq '.parameterGroups[] | select(.name == "Lake/Reservoir Storage") | {name, members}'

Live response summary on June 4, 2026:

{
  "name": "Lake/Reservoir Storage",
  "members": {
    "rise-edr": ["1470", "56", "51", "47", "3"],
    "usace-edr": [
      "Flood Storage",
      "Conservation Storage",
      "Percent Flood Pool",
      "Percent Conservation Pool"
    ],
    "resviz-edr": ["avg", "p10", "p90", "raw"],
    "teacup-edr": ["avg", "p10", "p90", "raw"]
  }
}

7. Finding stations or locations

Station-style collections advertise locations. Use a bbox first.

GET /collections/snotel-edr/locations?f=json&bbox=-107,37,-105,40 HTTP/1.1
Host: api.wwdh.internetofwater.app
Accept: application/geo+json, application/json

Full URL:

https://api.wwdh.internetofwater.app/collections/snotel-edr/locations?f=json&bbox=-107,37,-105,40

Equivalent curl:

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/snotel-edr/locations?f=json&bbox=-107,37,-105,40'

Expected response shape:

{
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "id": "303",
      "geometry": {
        "type": "Point",
        "coordinates": [-105.0, 37.3]
      },
      "properties": {
        "stationTriplet": "303:CO:SNTL",
        "name": "Apishapa",
        "stateCode": "CO",
        "networkCode": "SNTL"
      }
    }
  ]
}

The exact fields vary by provider. For RISE reservoirs you may see properties such as _id, locationName, timezone, elevation, and projectNames. For SNOTEL you may see stationTriplet, stationId, stateCode, networkCode, name, and huc.

8. One known station: /locations/{locId}

When you already know a provider’s location id, request data through the location endpoint. This example asks RISE for Lake Mead daily storage for January 2023.

GET /collections/rise-edr/locations/3514?f=json&datetime=2023-01-01/2023-01-31&parameter-name=3 HTTP/1.1
Host: api.wwdh.internetofwater.app
Accept: application/prs.coverage+json, application/json

Full URL:

https://api.wwdh.internetofwater.app/collections/rise-edr/locations/3514?f=json&datetime=2023-01-01/2023-01-31&parameter-name=3

Equivalent curl:

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/rise-edr/locations/3514?f=json&datetime=2023-01-01/2023-01-31&parameter-name=3'

Expected response shape:

{
  "type": "Coverage",
  "domain": {
    "domainType": "PointSeries",
    "axes": {
      "x": {"values": [-114.7]},
      "y": {"values": [36.0]},
      "t": {"values": ["2023-01-01T07:00:00Z"]}
    }
  },
  "ranges": {
    "3": {
      "type": "NdArray",
      "axisNames": ["t"],
      "values": [25000000]
    }
  }
}

CoverageJSON is compact and array-oriented. To make a table, pair the axis values in domain.axes with the values in each ranges parameter.

9. Many stations or grid cells: /cube

Use cube for bbox-based bulk retrieval when the collection advertises it. This is usually the best route for multiple stations or a small grid.

SNOTEL SWE example:

GET /collections/snotel-edr/cube?f=json&bbox=-106.2,39.6,-105.8,40.0&datetime=2024-02-01/2024-04-30&parameter-name=WTEQ HTTP/1.1
Host: api.wwdh.internetofwater.app
Accept: application/prs.coverage+json, application/json

Full URL:

https://api.wwdh.internetofwater.app/collections/snotel-edr/cube?f=json&bbox=-106.2,39.6,-105.8,40.0&datetime=2024-02-01/2024-04-30&parameter-name=WTEQ

PRISM grid example with two parameters:

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/usgs-prism/cube?f=json&bbox=-112.6,36.7,-112.2,37.1&datetime=2023-01-01/2023-02-28&parameter-name=ppt,tmx'

Expected CoverageJSON shape:

{
  "type": "CoverageCollection",
  "parameters": {
    "ppt": {
      "type": "Parameter",
      "description": {"en": "Mean monthly precipitation"}
    }
  },
  "coverages": [
    {
      "type": "Coverage",
      "domain": {
        "domainType": "Grid",
        "axes": {
          "x": {"values": [-112.56, -112.52]},
          "y": {"values": [37.06, 37.02]},
          "t": {"values": ["2023-01-01"]}
        }
      },
      "ranges": {
        "ppt": {
          "axisNames": ["t", "y", "x"],
          "values": [116.0, 120.0]
        }
      }
    }
  ]
}

Station collections may also return CoverageCollection, but each coverage is often a PointSeries rather than a Grid.

10. One point from a grid: /position

PRISM advertises position, which is useful when you want the time series at one longitude/latitude rather than a full grid.

GET /collections/usgs-prism/position?f=json&coords=POINT(-112.4%2036.9)&datetime=2023-01-01/2023-02-28&parameter-name=ppt HTTP/1.1
Host: api.wwdh.internetofwater.app
Accept: application/prs.coverage+json, application/json

Full URL:

https://api.wwdh.internetofwater.app/collections/usgs-prism/position?f=json&coords=POINT(-112.4%2036.9)&datetime=2023-01-01/2023-02-28&parameter-name=ppt

Equivalent curl:

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/usgs-prism/position?f=json&coords=POINT(-112.4%2036.9)&datetime=2023-01-01/2023-02-28&parameter-name=ppt'

Expected response:

{
  "type": "Coverage",
  "domain": {
    "domainType": "PointSeries",
    "axes": {
      "x": {"values": [-112.4]},
      "y": {"values": [36.9]},
      "t": {"values": ["2023-01-01", "2023-02-01"]}
    }
  },
  "ranges": {
    "ppt": {
      "axisNames": ["t"],
      "values": [116.0, 42.0]
    }
  }
}

11. Polygon queries: /area

When a collection advertises area, send a WKT polygon in coords. Use this for a watershed, district, or management boundary after you have simplified it enough for a URL.

Readable polygon:

POLYGON((-106 39,-105.8 39,-105.8 39.2,-106 39.2,-106 39))

Raw request shape:

GET /collections/snotel-edr/area?f=json&coords=POLYGON((-106%2039,-105.8%2039,-105.8%2039.2,-106%2039.2,-106%2039))&datetime=2024-02-01/2024-04-30&parameter-name=WTEQ HTTP/1.1
Host: api.wwdh.internetofwater.app
Accept: application/prs.coverage+json, application/json

For complex polygons, prefer an HTTP client that builds and encodes query parameters for you. Long URLs can hit browser, proxy, or server limits.

12. Feature layers: /queryables and /items

Collections without EDR data_queries are often feature layers. Use queryables to inspect attributes and items to retrieve features. EDR collections may also expose /items; in that case, treat /items as the feature catalog you use to discover stations, reservoirs, dams, and other locations before making a data query.

Queryables example:

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/snotel-huc06-means/queryables?f=json'

Expected response shape:

{
  "type": "object",
  "properties": {
    "geometry": {"$ref": "https://geojson.org/schema/Geometry.json"},
    "name": {"type": "string"},
    "geoconnex_url": {"type": "string"},
    "id": {"type": "string"},
    "basin_index": {"type": "number"}
  }
}

Items example:

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/snotel-huc06-means/items?f=json&limit=3'

Expected response shape:

{
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "id": "090400",
      "geometry": {"type": "MultiPolygon"},
      "properties": {
        "name": "Upper South Saskatchewan River",
        "basin_index": 75.4,
        "current_snow_water_equivalent_relative_to_thirty_year_avg": 75.4,
        "latest_full_day_of_data": "06-03"
      }
    }
  ]
}

Feature/catalog layers are not time-series sampling endpoints. Treat them as GIS feature downloads with attributes.

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/rise-edr/items?f=json&bbox=-115,33,-111,35&locationTypeName=Lake%2FReservoir&limit=20'

{
  "type": "FeatureCollection",
  "count": 7,
  "sample": [
    {
      "id": 3515,
      "locationName": "Lake Havasu Parker Dam and Powerplant",
      "locationTypeName": "Lake/Reservoir",
      "coords": [-114.1385, 34.2964]
    }
  ]
}

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/usace-edr/items?f=json&bbox=-115,33,-111,35&provider=SPL&limit=5'

{
  "type": "FeatureCollection",
  "count": 4,
  "sample": [
    {
      "id": 157145,
      "name": "Alamo Dam",
      "code": "Alamo",
      "state": "AZ",
      "provider": "SPL",
      "coords": [-113.6017, 34.23167]
    }
  ]
}

13. Cross-provider storage workflow

This workflow shows a complete verified pattern:

1. Find equivalent storage parameters.
2. Find a bbox that has both USBR RISE and USACE features.
3. Ask each provider for all available 2024 storage observations.

The shared bbox used here is a small area containing one matching RISE feature and one matching USACE feature:

-114.3,34.1,-113.5,34.4

It contains USBR RISE lake/reservoir features such as Lake Havasu Parker Dam and Powerplant (3515) and USACE features such as Alamo Dam (157145).

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/rise-edr/cube?f=json&bbox=-114.3,34.1,-113.5,34.4&datetime=2024-01-01/2024-12-31&parameter-name=3'

{
  "type": "CoverageCollection",
  "parameterKeys": ["3"],
  "coverageCount": 1,
  "sample": [
    {
      "x": -114.1385,
      "y": 34.2964,
      "t_count": 365,
      "t_first": "2024-01-01T07:00:00+00:00",
      "t_last": "2024-12-30T07:00:00+00:00",
      "value_count": 365,
      "first_values": [578564.0, 579452.0, 579225.0]
    }
  ]
}

curl -sS \
  'https://api.wwdh.internetofwater.app/collections/usace-edr/cube?f=json&bbox=-114.3,34.1,-113.5,34.4&datetime=2024-01-01/2024-12-31&parameter-name=Flood%20Storage'

{
  "type": "CoverageCollection",
  "parameterKeys": ["Flood Storage"],
  "coverageCount": 1,
  "sample": [
    {
      "x": -113.6017,
      "y": 34.23167,
      "t_count": 8300,
      "t_first": "2024-01-01T00:00:00+00:00",
      "t_last": "2024-12-31T00:00:00+00:00",
      "value_count": 8300,
      "first_values": [136286.17, 136286.17, 136286.17]
    }
  ]
}

/collections?f=json
  -> parameterGroups for concept mapping
/collections/{id}/queryables?f=json
  -> feature property names
/collections/{id}/items?f=json&bbox=...&{queryable}=...
  -> candidate location ids
/collections/{id}/locations/{locId}?f=json&datetime=2024-01-01/2024-12-31&parameter-name=...
  -> full 2024 series for one location
/collections/{id}/cube?f=json&bbox=...&datetime=2024-01-01/2024-12-31&parameter-name=...
  -> all matching series in a bbox, when the provider can satisfy it

14. Response types in practice

You will usually see one of these JSON shapes.

GeoJSON feature collection:

{
  "type": "FeatureCollection",
  "features": []
}

GeoJSON single feature:

{
  "type": "Feature",
  "geometry": {},
  "properties": {}
}

CoverageJSON single coverage:

{
  "type": "Coverage",
  "domain": {
    "domainType": "PointSeries",
    "axes": {}
  },
  "ranges": {}
}

CoverageJSON collection:

{
  "type": "CoverageCollection",
  "parameters": {},
  "coverages": []
}

A simple tabular interpretation of CoverageJSON is:

coverage id + parameter id + datetime + x + y + z + value

The hard part is axis ordering. ranges.{parameter}.axisNames tells you the order of dimensions for the flat values array.

15. A language-agnostic workflow

Use this sequence in any tool:

1. GET /collections?f=json
2. Pick collection.id.
3. GET /collections/{id}?f=json
4. If parameter_names exists, choose exact parameter keys.
5. If data_queries.locations exists, inspect /collections/{id}/locations?f=json&bbox=....
6. If data_queries.cube exists, retrieve data with /collections/{id}/cube?f=json&bbox=...&datetime=...&parameter-name=....
7. If you need to discover feature ids or filter a feature catalog, use /collections/{id}/queryables?f=json and /collections/{id}/items?f=json&{queryable}=....
8. Parse GeoJSON as features or CoverageJSON as axis/range arrays.
9. Expand the spatial or temporal scope only after the small request works.

16. Troubleshooting raw requests

Keep requests small while exploring. A good first request has one bbox, one parameter, and a short date range. Once it succeeds, widen only one dimension at a time.