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CivilsRoute ResourcesA practical reference to the National Highways datasets UK civil and highways engineers use for scheme appraisal — how the network is organised, what each dataset contains, and where the authoritative source lives.
The Strategic Road Network is the ~4,500 miles of motorways and major A-roads in England managed by National Highways (formerly Highways England, and before that the Highways Agency). It carries roughly a third of all traffic and two thirds of freight, but represents only about 2% of England's road length. Everything else — local A-roads, B-roads and minor roads — is managed by the relevant local highway authority.
For a scheme touching or crossing the SRN, National Highways is a statutory consultee, and its data underpins Transport Assessments, road safety audits, structures interaction reports and abnormal load route assessments.
National Highways delivers operations, maintenance and renewals through seven operational regions:
Each region is built from one or more numbered maintenance areas — the historic delivery-contract units. A separate Area 5 covers the M25 and connected network around London. The mapping between regions and areas is approximately:
| Region | Maintenance area(s) | Broad coverage |
|---|---|---|
| South West | Area 1 / Area 2 (Area 38 in CivilsRoute data) | Cornwall, Devon, Somerset, Dorset, Wiltshire, Gloucestershire |
| South East | Area 3, Area 4 | Kent, Sussex, Surrey, Hampshire, Berkshire, Oxfordshire |
| London | Area 5 | M25 and radial approaches |
| East | Area 6, Area 8 | Essex, Suffolk, Norfolk, Cambridgeshire, Bedfordshire, Hertfordshire |
| East Midlands | Area 7 | Northamptonshire, Leicestershire, Lincolnshire, Nottinghamshire, Derbyshire |
| West Midlands | Area 9 | Birmingham conurbation, Staffordshire, Warwickshire, Worcestershire, Herefordshire, Shropshire |
| North West | Area 10, Area 13 | Cheshire, Greater Manchester, Merseyside, Lancashire, Cumbria |
| North East | Area 12, Area 14 | Yorkshire, County Durham, Tyne & Wear, Northumberland |
In CivilsRoute: the NH Operational Regions overlay (Layers panel → folder 1) draws all seven region boundaries plus London at once, colour-coded, each with a permanent label showing the region name and its area number(s). It is a national overview and is not tied to your active region.
Area boundaries and numbering have changed over successive maintenance contracts (Managing Agent Contractor, Asset Support Contract, and the current Regional Delivery Partnership / operations contracts). Always confirm the current arrangement with National Highways for a live scheme.
WebTRIS is the National Highways Traffic Information System. It publishes traffic counts from permanent monitoring sites (inductive loops and other sensors) across the SRN, including:
AADT is the headline input for capacity checks, Transport Assessments, noise and air-quality screening, and pavement design traffic loading. For local roads off the SRN, the equivalent open dataset is the DfT road traffic statistics (manual and automatic count points), which CivilsRoute also draws on for A-road and minor-road AADF figures.
In CivilsRoute: WebTRIS sites plot as clickable markers; the traffic-data view exports a formatted AADT report. DfT AADF count points provide off-network coverage.
STATS19 is the statutory road collision reporting system. Police forces record every personal-injury collision on a public road in Great Britain using the STATS19 form; the Department for Transport publishes the aggregated, anonymised dataset annually as open data.
Each record typically includes:
STATS19 is the core evidence base for Road Safety Audits, safety schemes, and the collision-history section of scheme business cases. Note the well-documented caveats: slight injuries are under-reported, severity reporting changed with the introduction of injury-based (CRASH/CRaSH) systems around 2016–2019, and coordinates are approximate.
In CivilsRoute: STATS19 points are clustered spatially and filterable by year. The Start Crash Selection tool lets you draw a polygon around a junction or link and returns an instant Fatal / Serious / Slight breakdown for everything inside it.
National Highways maintains asset inventories for the SRN, including a structures database covering overbridges, underbridges, footbridges, gantries, retaining walls, culverts and other structures. Each structure carries a reference identifier used across inspection, assessment and maintenance records.
For engineers, the structures layer supports preliminary route corridor appraisal, structures interaction reporting, headroom and abnormal-load route checks, and identifying third-party assets near a scheme. Detailed inspection and assessment data is not open — it is obtained from National Highways under a data request or through the project's information protocols.
Emergency Areas (ERAs) are the refuge laybys on motorways without a permanent hard shoulder (all-lane-running and dynamic hard-shoulder smart motorway sections). Their spacing and location are relevant to operational assessments and to schemes interfacing with smart-motorway infrastructure. National Highways publishes ERA locations as open data.
Variable Message Signs (VMS) and the wider network of signs and signals are published in near-real time through the National Highways DATEX II feeds from the National Traffic Information Service (NTIS). The live VMS message content gives useful operational context during surveys and traffic-management planning.
The Design Manual for Roads and Bridges (DMRB) is the suite of standards, advice notes and specifications for the design, assessment and operation of trunk roads and motorways in the UK. It is maintained by National Highways on behalf of the UK Overseeing Organisations (National Highways, Transport Scotland, the Welsh Government and the Department for Infrastructure in Northern Ireland) and is freely available through the Standards for Highways website.
Related documents an engineer will commonly reference alongside a CivilsRoute session include the Manual of Contract Documents for Highway Works (MCHW), and, for local roads, Manual for Streets and the local highway authority's own design guide.
CivilsRoute is a visualisation and planning aid. All figures, boundaries and asset positions must be verified against the originating source and confirmed on site before they are relied on for design or construction.
Free, browser-based, no sign-up. Toggle AADT, STATS19, structures and the operational-regions overlay together.
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