> 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-downloads.md).

# OS MasterMap Water Network Layer Downloads

This page provides downloadable files to support the product in use.

{% hint style="warning" %}

#### Product has reached its End of Life (withdrawal) date

The OS MasterMap Water Network Layer product (also referred to as OS MasterMap Networks – Water Layer) reached its End of Life on **31 March 2026**. As of this date, Ordnance Survey ceased to maintain or publish updates to the product, and access to the product was removed from the OS Data Hub, OS Features API and OS Vector Tile API.

Supporting product documentation will be removed from this site 12 months after this date, when access to existing data packages in the OS Data Hub is no longer available. Full details, including migration information and FAQs, are available on the [OS MasterMap Water Network Layer End of Life information page](/os-downloads/resources/product-resources/end-of-life-product-documentation/os-mastermap-water-network-layer/os-mastermap-water-network-layer-end-of-life-information.md).
{% endhint %}

## XML code lists

XML versions of the OS MasterMap Water Network Layer code lists are available below:

* [HydroNodeCategoryValue.xml](https://www.ordnancesurvey.co.uk/xml/codelists/HydroNodeCategoryValue.xml)
* [LevelOfDetailValue.xml](https://www.ordnancesurvey.co.uk/xml/codelists/LevelOfDetailValue.xml)
* [ReasonForChangeValue.xml](https://www.ordnancesurvey.co.uk/xml/codelists/ReasonForChangeValue.xml)
* [WatercourseFormValue.xml](https://www.ordnancesurvey.co.uk/xml/codelists/WatercourseFormValue.xml)
* [WatercourseProvenanceValue.xml](https://www.ordnancesurvey.co.uk/xml/codelists/WatercourseProvenanceValue.xml)
* [WatercourseTypeValue.xml](https://www.ordnancesurvey.co.uk/xml/codelists/WatercourseTypeValue.xml)

Code lists provide a controlled list and formal definition for values used in certain attributes of the product.

## XML schema

The XML schema for OS MasterMap Water Network Layer is available from the [XML resources page on the Ordnance Survey website](https://www.ordnancesurvey.co.uk/xml/schema/waternetwork/v1/index.html).

#### OS MasterMap Water Network Schema v1

* [waterNetwork.xsd](https://www.ordnancesurvey.co.uk/xml/schema/waternetwork/v1/waterNetwork.xsd)

The general network schema is also relevant to this product:

* [generalNetwork.xsd](https://www.ordnancesurvey.co.uk/xml/schema/network/v1/generalNetwork.xsd)

{% hint style="info" %}
The XML File Repository License, covering the terms and conditions for the use of all Ordnance Survey XML schemas, is made available through the [Terms and Conditions page](/os-downloads/resources/site-resources/terms-and-conditions.md) in the Resources section.
{% endhint %}


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