Skip to content

Freshness and availability

Transportation data changes quickly, but upstream systems do not all update at the same cadence. WAC reports freshness as an expectation, not a guarantee.

Update cadence

The implemented source catalog lists the configured cadence for each implemented source when it is available. A cadence describes how often WAC expects to revisit a source, not a promise that the upstream data changed.

Why data may be stale

Data can be delayed or unavailable for several reasons:

  • the upstream source is temporarily down.
  • a camera is offline or showing a placeholder image.
  • a provider changes its published data structure.
  • a public feed omits location, direction, or status fields.
  • WAC suppresses a record because the latest usable image or metadata is too old.

How to interpret WAC

Use WAC as a helpful public map layer. For safety-critical decisions, verify conditions with the upstream agency, official 511 service, local authorities, or roadside information.