> 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/using-os-ngd-data/os-ngd-transport/transport-networks-in-the-os-ngd/streets-and-asset-management-information.md). # Streets and asset management information This page covers the Street and Highway Dedication Feature Types and the asset management information feature types of the OS RAMI Collection. Streets and associated feature types make up the Highway Authority view of the road and path network. While not used for routing use cases, these feature types are key datasets for asset management use cases and can be joined to the OS road and path network via cross reference tables. ## Street Feature Type While [Road Links](/osngd/data-structure/transport/transport-network/road-link.md) and [Path Links](/osngd/data-structure/transport/transport-network/path-link.md) represent the OS-surveyed definition of a road or path, a [Street feature](/osngd/data-structure/transport/transport-network/street.md) represents the Street as defined in the National Street Gazetteer or the National Street Gazetteer for Scotland. Streets are identified by their unique and persistent identifiers: Unique Street Reference Numbers (USRNs). USRNs representing a whole street are made up of individual Elementary Street Units (ESUs). Each authority is provided a USRN range that is centrally allocated and managed by GeoPlace in England and Wales, and by Improvement Service in Scotland. (Please note, you should read the term 'Highways' as 'Roads' when applied to Streets in Scotland.) Street features provide attribution required to adhere to [BS7666](https://landingpage.bsigroup.com/LandingPage/Series?UPI=BS%207666): * [**USRN**](/osngd/data-structure/transport/transport-network/street.md#usrn): The USRN is the unique and persistent identifier of a Street assigned by the Roads or Highway Authority. * **Street type (**[**Description attribute**](/osngd/data-structure/transport/transport-network/street.md#description)**)**: The type of gazetteer record to which the USRN relates. It's mandatory for all USRNs to be assigned a Street Type. * **Operational state (**[**Operational State attribute**](/osngd/data-structure/transport/transport-network/street.md#operationalstate)**)**: Indicates whether the Street is proposed, under construction, open, or closed (permanently or temporarily). * **Responsible authority (**[**Responsible Authority Identifier**](/osngd/data-structure/transport/transport-network/street.md#responsibleauthority_identifier) **and** [**Responsible Authority Name**](/osngd/data-structure/transport/transport-network/street.md#responsibleauthority_name) **attributes)**: Reference to the authority who performs an administrative function – notably naming and numbering. A Street will split when it crosses the boundary of an administrative area where the local maintenance responsibility changes. A Street could also split at a town or locality boundary to allow properties to be located uniquely upon a Street via a unique identifier (i.e. a USRN). In the OS NGD, Streets are represented spatially as line features, the geometry of which is determined by whether they have been matched to a Road Link or Path Link. Where possible, the geometry of a Street captured by a roads or highway authority is spatially matched to the geometry of a Road Link or Path Link. 1. If any of the Street’s ESUs have been matched to (a) Road Link(s) / Path Link(s), then the aggregated geometry of the matched Road Link(s) / Path Link(s) will be provided for the Street feature. 2. If none of the Street’s ESUs have been matched to (a) Road Link(s )/ Path Link(s), then the aggregated geometry of the ESUs (captured by the roads or highway authority) will be provided for the Street feature. If a Street has been matched to a Road Link or Path Link, this connection is represented through the [Road Link Reference table](/osngd/data-structure/transport/transport-network/street.md#road-link-reference) or [Path Link Reference table](/osngd/data-structure/transport/transport-network/street.md#path-link-reference), respectively. ### Links to and from Streets The following table describes all the links to and from Streets within the OS NGD Transport Theme:
Source Feature TypeForeign Key AttributeDestination Feature Type
Street (Road Link Reference)roadlinkidRoad Link
Street (Path Link Reference)pathlinkidPath Link
Highway Dedication (Highway Dedication Network Reference)networkreferenceidStreet
Maintenance AreausrnStreet
Maintenance LineusrnStreet
Maintenance PointusrnStreet
Reinstatement AreausrnStreet
Reinstatement LineusrnStreet
Reinstatement PointusrnStreet
Special Designation AreausrnStreet
Special Designation LineusrnStreet
Special Designation PointusrnStreet
### Street and Road Link naming When Road Links are surveyed by OS, the signed road name is captured and assigned to the Road Link (see also the [Road Link Feature Type section of the Road network page](/osngd/using-os-ngd-data/os-ngd-transport/transport-networks-in-the-os-ngd/road-network.md#road-link-and-road-node-feature-types)). If a Road Link has been matched to a Street feature with a street type of Designated Street Name, and this name differs from the OS-surveyed name, then the authoritative name from the Street feature will be used as the principal name, and the OS-surveyed name will be used as an alternate name. This may happen where languages differ or if a road has many names. If a Road Link does not have a matched Street feature, then the OS-surveyed name will be used. ## Asset management information feature types Associated with [Street](/osngd/data-structure/transport/transport-network/street.md) data are the various maintenance, reinstatement and special designation feature types: * [Maintenance Area](/osngd/data-structure/transport/rami/maintenance-area.md) * [Maintenance Line](/osngd/data-structure/transport/rami/maintenance-line.md) * [Maintenance Point](/osngd/data-structure/transport/rami/maintenance-point.md) * [Reinstatement Area](/osngd/data-structure/transport/rami/reinstatement-area.md) * [Reinstatement Line](/osngd/data-structure/transport/rami/reinstatement-line.md) * [Reinstatement Point](/osngd/data-structure/transport/rami/reinstatement-point.md) * [Special Designation Area](/osngd/data-structure/transport/rami/special-designation-area.md) * [Special Designation Line](/osngd/data-structure/transport/rami/special-designation-line.md) * [Special Designation Point](/osngd/data-structure/transport/rami/special-designation-point.md) These feature types provide asset management information, including the authority responsible for maintaining each Street. This information is sourced from the National Street Gazetteer or the National Street Gazetteer for Scotland and is not collected by Ordnance Survey. For further information on the National Street Gazetteer, please refer to the [National street gazetteers, Geoplace and Improvement Service page](/osngd/using-os-ngd-data/os-ngd-transport/transport-networks-in-the-os-ngd/national-street-gazetteers-geoplace-and-improvement-service.md). Maintenance, reinstatement and special designation features are represented spatially as either area, line or point features, depending on how the highway authority has submitted the data.
Example visualisations showing Maintenance Line, Maintenance Point and Maintenance Area features. Background maps have been included to provide context.

Example visualisations showing Maintenance Line, Maintenance Point and Maintenance Area features. Background maps have been included to provide context.

### Links to and from maintenance, reinstatement and special designation feature types
Data model of data cross referencing for the Steet and various asset management information feature types in the OS NGD.

Data model of data cross referencing for the Steet and various asset management information feature types in the OS NGD.

The link back to the Street to tell you which Streets the asset management information feature applies to is provided through the USRN attribute: | Source Feature Type | Foreign Key Attribute | Destination Feature Type | | ---------------------------------------------------------------------------------------------- | --------------------- | --------------------------------------------------------------------- | | [Maintenance Area](/osngd/data-structure/transport/rami/maintenance-area.md) | `usrn` | [Street](/osngd/data-structure/transport/transport-network/street.md) | | [Maintenance Line](/osngd/data-structure/transport/rami/maintenance-line.md) | `usrn` | [Street](/osngd/data-structure/transport/transport-network/street.md) | | [Maintenance Point](/osngd/data-structure/transport/rami/maintenance-point.md) | `usrn` | [Street](/osngd/data-structure/transport/transport-network/street.md) | | [Reinstatement Area](/osngd/data-structure/transport/rami/reinstatement-area.md) | `usrn` | [Street](/osngd/data-structure/transport/transport-network/street.md) | | [Reinstatement Line](/osngd/data-structure/transport/rami/reinstatement-line.md) | `usrn` | [Street](/osngd/data-structure/transport/transport-network/street.md) | | [Reinstatement Point](/osngd/data-structure/transport/rami/reinstatement-point.md) | `usrn` | [Street](/osngd/data-structure/transport/transport-network/street.md) | | [Special Designation Area](/osngd/data-structure/transport/rami/special-designation-area.md) | `usrn` | [Street](/osngd/data-structure/transport/transport-network/street.md) | | [Special Designation Line](/osngd/data-structure/transport/rami/special-designation-line.md) | `usrn` | [Street](/osngd/data-structure/transport/transport-network/street.md) | | [Special Designation Point](/osngd/data-structure/transport/rami/special-designation-point.md) | `usrn` | [Street](/osngd/data-structure/transport/transport-network/street.md) | Special designation features include an additional cross-reference table ([Date Time Qualifier](/osngd/data-structure/transport/rami/special-designation-area.md#date-time-qualifier)) describing if a special designation only applies at particular times of day, week, month or year (for example, only in School Hours). ## Highway Dedication Feature Type Also associated with [Street](/osngd/data-structure/transport/transport-network/street.md) data is the [Highway Dedication Feature Type](/osngd/data-structure/transport/rami/highway-dedication.md), which indicates which types of user have access to the given section of the highway. Highway Dedication features are represented spatially as line features with the geometry of the Elementary Street Unit/s (ESUs) to which they are associated. Additionally, for each Highway Dedication feature, the identifier of the ESU can be found in the [Authority ID attribute](/osngd/data-structure/transport/rami/highway-dedication.md#authorityid); this attribute is a string of up to 25 characters comprised of the characters “esu” followed by three parts separated by “\_”: * The Local Highway Authority (LHA) authority code * The ESU it references * The dedication code in the National Street Gazetteer (NSG) For example: esu1050\_4251330353463\_4 ### Links to and from Highway Dedication The link back to the road and path network is represented through the [Highway Dedication Network Reference table](/osngd/data-structure/transport/rami/highway-dedication.md#highway-dedication-network-reference), which identifies the Street that each Highway Dedication feature relates to and if the Street has been matched to (a) Road Link(s) or Path Link(s), plus a reference to the relevant Road Link(s) or Path Link(s) as well. | Source Feature Type | Foreign Key Attribute | Destination Feature Type | | ------------------------------------------------------------------------------------------------------------------------------------------------------------ | --------------------- | --------------------------------------------------------------------------- | | [Highway Dedication](/osngd/data-structure/transport/rami/highway-dedication.md#highway-dedication-network-reference) (Highway Dedication Network Reference) | `networkreferenceid` | [Road Link](/osngd/data-structure/transport/transport-network/road-link.md) | | [Highway Dedication](/osngd/data-structure/transport/rami/highway-dedication.md#highway-dedication-network-reference) (Highway Dedication Network Reference) | `networkreferenceid` | [Path Link](/osngd/data-structure/transport/transport-network/path-link.md) | | [Highway Dedication](/osngd/data-structure/transport/rami/highway-dedication.md#highway-dedication-network-reference) (Highway Dedication Network Reference) | `networkreferenceid` | [Street](/osngd/data-structure/transport/transport-network/street.md) | --- # Agent Instructions This documentation is published with GitBook. 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