Why your local road may have no traffic data

Major network and minor network use different designs

DfT produces AADF for every junction-to-junction link on motorway and A-road network. Minor network is too large for equivalent coverage. B roads, C roads and unclassified roads use samples. Many residential streets have never belonged to a national minor-road sample, so no official street-level count exists for them.

Map can only display published count locations. Adding colour to every street would imply evidence that dataset does not contain. For this reason, smaller roads appear only when zoomed in and only matched roads with data receive traffic colours.

Why nearest result may be another road

Postcode search creates geographic starting point, then sorts official locations by straight-line distance. Closest count point can sit on parallel street, connecting road or nearby main route. Number describes pinned road link—not every street inside search radius. Distance helps users see this distinction.

Dense urban grids increase risk of mistaken identity. Always read road name, map line and count-point location together. If searched street stays grey, no matched count data is available there even if result list contains nearby roads.

Why an old local-road point remains visible

Minor-road samples change over time. A road included in an older sample may not belong to latest annual panel. Historic point still has value for showing past observed or estimated conditions, but recent year may be absent. Site chooses latest row available for that count point and prints year explicitly rather than silently presenting it as current.

Road names create another matching challenge

DfT often labels minor roads only as U or C class. Site matches coordinates against nearby named OpenStreetMap highway geometry within conservative distance. Most U/C locations gain readable names; some remain generic because no reliable nearby name exists. Generic label is safer than attaching wrong street name.

What you can do when data is missing

• Zoom in and check neighbouring coloured roads.
• Search local council traffic-count portal.
• Review transport statements attached to nearby planning applications.
• Ask highway authority whether recent automatic or manual survey exists.
• For critical decision, commission time-specific traffic survey.

Do not transfer nearby A-road volume onto residential street. Nearby major route may explain area context, but its flow cannot estimate unmeasured side road.

What “no data” does and does not mean

No data means no suitable published DfT count point matched in current release. It does not mean zero traffic, road closure or unusually quiet conditions. Absence is coverage fact, not traffic rating. Honest map should preserve that uncertainty rather than fill every gap.