Sources, meaning and limits
The dashboard combines observed traffic flow with reported roadway events, then labels what is measured, calculated, historical or unavailable.
From source to screen
The dashboard adds context without pretending an estimate is a sensor reading.
Read traffic speeds and roadway reports.
Keep only the tracked roads and mile markers.
Retain current state and useful history.
Show current conditions beside historical context.
Source layer
Traffic is observed. Incidents are reported. The interface keeps that distinction intact.
Scheduled TomTom observations become corridor, speed-zone and half-mile traffic history.
CDOT incidents and planned events are filtered to the tracked corridor and mile-marker bounds.
Roadway report placement
The provider mile marker is the hard gate. Geometry then improves where the report appears.
A named route that does not match the corridor is rejected.
The reported point or range must overlap the configured corridor bounds.
Centroid geometry is projected to the nearest point on the configured road shape.
Nearby geometry uses calibrated anchors. Otherwise, a valid provider point or range places the report.
Reading the dashboard
Use the label beside a value to tell whether it came from a source, a check, a calculation or matched history.
TomTom or CDOT was successfully read at the time shown. A repeated value can still be a new reading.
“Current” is based on when it was observed—not whether the speed or incident changed.
Travel time adds the road sections together. It is not a measured end-to-end trip.
The same weekday and hour from the previous 13 completed weeks—not a generic average.
Derived views
Each view is built from retained observations; none creates a new measurement.
Complete half-mile cells are summed. Corridor average is only the fallback when full cell coverage is unavailable.
Reading the latest retained 15-minute estimates…
Complete 15-minute speed-zone estimates are compared on Denver time. Partial buckets are excluded, and the comparison restarts at midnight.
The rolling profile uses the preceding 13 completed weeks and matches the same Denver weekday and hour. The band describes variation, not certainty.
Seven- and 30-day colors show how often slowdown conditions occurred along each one-mile interval shown on the per-corridor map.
History and coverage
Retention moves data into queryable history. It does not erase it to make the live tables smaller.
Current corridor, zone, incident and map state.
Older corridor samples remain in the same history reads.
Corridor summaries, speed zones and map cells each preserve their observations.
Durable coverage begins September 24, 2026 at 21:00 UTC.
Looking for a specific date? Available history depends on the dataset. The coverage note records when retained observations begin.
Interpretation limits
These three limits stay visible so an estimate is not mistaken for a direct measurement.