> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/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/os-downloads/resources/product-resources/end-of-life-product-documentation/os-mastermap-water-network-layer/os-mastermap-water-network-layer-getting-started-guide/structure-of-the-supplied-data.md).

# Structure of the supplied data

OS MasterMap Water Network Layer is supplied in three formats: Geography Markup Language (GML 3.2.1), GeoPackage and vector tiles. All formats are compressed into a regular zip file (.ZIP).

Before loading the data, you will need to unzip it by using any of the regular zip programs available or via the facility within the Windows 10 operating system.

## Area of interest order type <a href="#bookmark8" id="bookmark8"></a>

The tiled dataset will be provided in 5km x 5km square tiles and will contain all features present in the tile(s) ordered.

The data is supplied as 'hairy tiles', in that no feature is broken at the tile edge but is included across the tile boundary if it extends into an adjacent tile. As such, a data holding comprising more than one 5km² tile will contain duplicate features which may need to be removed depending upon the user requirement.

The GeoPackage and vector tiles formats will be available for Great Britain coverage only. The file naming convention will be as follows:

* GML: 5km² tile ID. gz, for example: HP4500.gz
* GeoPackage: MMNWGB.gpkg
* Vector tiles: MMNWGB.mbtiles

## Data ordering and download <a href="#bookmark9" id="bookmark9"></a>

* Direct customers and OS Partners, please contact your Account Manager or Business Enquiries.
* For Public Sector Geospatial Agreement (PSGA) customers, the product is available to you through the PSGA Contract.

The data is available as an online download via the [OS Data Hub](https://osdatahub.os.uk/).

## Download contents <a href="#bookmark10" id="bookmark10"></a>

The data is supplied in a .zip archive, which contains a parent folder with two sub-folders entitled DATA and DOC, and an additional readme file.


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