OS MasterMap Topography Layer upgrade

Improved descriptive terms attribution allows you to identify, interrogate and visualise more features than ever before!

OS MasterMap Topography Layer's Descriptive terms will update over 11 million features across land, rivers, water and structures. See a full list of newly identifiable features in our Excel guide or request the sample data


When will the new descriptive terms be available?

There will be a staged roll-out of descriptive terms into the main OS MasterMap Topography Layer product, subject to change.


Why is the agricultural land data divided into regions?

We’re releasing our agricultural land data by region so that you can manage the data volumes more easily and efficiently.

Our updates cover both England and Wales in one group, and Scotland in another. We will be starting with the northern parts of each region in our October release; the southern parts will be available in our second release in November 2017. Note that this release schedule only applies to our agricultural land data and not our other MasterMap Topography updates, and only affects our October and November data releases.

The data roll-out process

The map below shows the current roll-out process:

  • Green indicates areas which are complete and were available in the first release in October.
  • Yellow shows areas which are incomplete and are still being worked on. Some updates was available in the first release in October; others were provided in November.
  • Red shows areas that are pending processing and was provided in the second release in November.

Agriculture data roll-out map


Why are there locations missing in the Agricultural Land release?

The data being rolled out in these releases reflects the data at its current state following cyclical updates as part of a three year programme. There are a few areas which have yet to be updated as part of this programme and these will be included in the coming months.

Why am I getting feature types that are not scheduled for release yet?

While most of the features will be updated to schema 9 within their particular categories (Argicultural land, Rivers, Water, Land and Structures), the new schema will also apply to features being updated as part of our content improvement programmes. Therefore, it's possible that you will recieve an updated feature in your COU, for example, a bridge, that reflects the changed schema despite the land and structures update not being deployed yet.


Why has the Rivers release been split in two?

We've decided to scale down our pace of release in response to customer feedback. We will be splitting our Rivers dataset into two releases to ensure our users have time to ingest and deploy the new changes.

This will unfortunately delay our overall schedule, but should help us continue to implement these exciting changes while maintaining the level of service expected by our customers and Partners. We'll continue to monitor the provision of the Schema 9 rollout and will endeavour to keep all our customers and Partners informed of any changes to the schedule of the remaining update period.

Why are there Land and Structures included in the Rivers update?

We'll be including some land and structures in the later rivers update. This should provide customers with a consistent number of feature updates and ensure a smooth transition between descriptive groups. The green areas in the image below will be included within the Rivers (South) release:



Agriculture data roll-out map


What can descriptive terms be used for?

Land use analysis

Identify agricultural land, foreshore, saltmarsh and others to more accurately describe your land cover and terrain

Risk modelling

Assess value and risk by evaluating land use, water, structures and specific features in your area of interest

Flooding Resilience

Detailed water features and foreshore, substations, structures, for risk analysis and fast access in an emergency

What descriptive terms are available?

We’re adding 76 new descriptive terms, such as bridge, level crossing and wind turbine. With 11 million more real-world features identified, you can tag and analyse your assets more precisely.


Through the creation of the descriptive group of 'structure', individual built features can now be identified and categorised. From emergency telephones and bridges to wind turbines and telecommunications masts, a wide range of features are becoming available.

Agricultural land

A brand new descriptive term, this will be applied to areas of land with the main purpose of growing crops or keeping livestock. Along with additional foreshore and land-fill descriptive term attributes, this makes land use much clearer.

Clearer tide lines

The updated descriptive terms give a clearer depiction of tidal range. Where high and low tide are coincident (e.g in docks used by larger ships, which are always full), the descriptive terms for Mean High Water (Springs) will appear with Mean Low Water (Springs) or other features such as Groyne or Building Outline.

How can they be styled?

We’re introducing new styling options for both current and upgraded Topography Layer including style sheets in SLD, LYR and QML formats.

These are available on GitHub, supported by version control, user guides and release notes.

Styling resources:

OSMM Topography Layer stylesheets on Github

Cartographic styling update for new descriptive terms (PDF)

Full Topography Layer user guide (PDF)

Descriptive terms sample data

We’ve been working with our partners and software vendors to ensure they’re ready for these changes. If you create your own software or systems to translate Topography Layer, this change could affect you, so please test this sample data.

This sample data covers two areas - Exeter and Hampshire/Isle of Wight.

For existing OS Partners please contact the partner team to request your sample data

For all other audiences, please use this sample data file (4.8 GB file)

If you need any additional help with sample data, please contact our Customer Services team.

More Questions? Get in touch

If you have more questions about descriptive terms, please use the forum, or contact us directly:

OS MasterMap Topo forum

Contact us via email