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About the project

The Geoconnex project is about providing technical infrastructure and guidance to create an open, community-contribution model for a knowledge graph linking hydrologic features in the United States, published in accordance with Spatial Data on the Web best practices as an implementation of Internet of Water principles.

In short, Geoconnex aims to make water data as easily discoverable, accessible, and usable as possible.

Please see for more detailed documentation than is available from this website.

What is Geoconnex?

Geoconnex aims to enable a knowledge graph for water data in the United States. The value of this graph, (see can be illustrated considering two use cases:

  1. Indexing and discovering models and research from public sector, private sector, or academic projects about a particular place or environmental feature.
  2. Building a federated multi-organization monitoring network in which all member-systems reference common monitored features and are discoverable through a community index.

See for a mockup of data discovery and access workflows that aspires to enable.

Architecturally, Geoconnex involves:

  1. A set of community-curated web resources about hydrologic Reference features (e.g. watersheds, monitoring locations, dams, bridges, etc.) about which many organizations may collect and publish data.
  2. Web resources about hydrologic features that organizations publish on the web, including embedded JSON-LD metadata, using common ontologies such as, and domain-specific ontologies such as HY-Features for hydrology and SOSA/SSN for sensor data. Guidance for embedded JSON-LD is under development at
  3. A registry of persistent identifiers (PIDs) that point to the above resources. The PIDs in the geoconnex system have the base URI Learn how to submit identifiers for the registry here: CONTRIBUTING. PIDs are important to maintain so that data publishers can change the URLs of their web resources while the knowledge graph and any search engine remain functional (preventing link rot).
  4. A harvester that collects the JSON-LD published above, and publishes the resulting knowledge graph as both a public domain data product and an open API, allowing for the building of search interfaces. The harvester codebase is under development at, and the knowledge graph itself will be available from

See the figure below: image

What is in

The features registered in are automatically harvested and included in are either community reference features or associated with a particular organization or database. See Geoconnex Features App for a simple map-based search interface for features in geoconnex.

  1. community reference features: monitoring and environmental features collated by a person or group in the interest of the community. These features are available via OGC API Features at
  2. organization specific features: features owned by a particular organizational entity or from a specific dataset.

Guidance for contributing PIDs and reference features is available here.



The contents of the project are public domain. All contributors to the project dedicate their contribution to the public domain. For more information, see