> For the complete documentation index, see [llms.txt](https://docs.os.uk/osngd/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/osngd/code-lists/code-lists-overview/waterlinkgeometrysourcevalue.md).

# waterlinkgeometrysourcevalue

This code list is used in association with the Geometry Source attribute which is present within the Water Link Feature Type. The code list describes where the geometry of the feature originated.

| Label                       | Definition                                                                                                                                                                                     |
| --------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Local Authority Inferred    | Link created using local authority knowledge.                                                                                                                                                  |
| Local Authority Surveyed    | Link surveyed by local authority.                                                                                                                                                              |
| National Authority Inferred | Link created using national authority knowledge (for example, EA or SEPA).                                                                                                                     |
| National Authority Surveyed | Link surveyed by national authority (for example, EA or SEPA).                                                                                                                                 |
| Ordnance Survey Area        | Link created using OS large-scale inland and tidal water area features (representing a watercourse greater than 1m wide in urban areas, 2m wide in rural areas and 5m wide in moorland areas). |
| Ordnance Survey Inferred    | Link created in an inferred alignment (usually for culverts and tunnels).                                                                                                                      |
| Ordnance Survey Line        | Link created using OS large-scale single water feature lines (representing a watercourse less than 1m wide in urban areas, 2m wide in rural areas and 5m wide in moorland areas).              |


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