Provisional Data
Reviewed • Standard Hydrology Definition • WaterLakeLevel
# Provisional Data
When you check water levels on WaterLakeLevel or the USGS website, readings from the past several days are routinely tagged with the status Provisional (qualifier `P`).
- Unreviewed Telemetry: The numbers are raw sensor readings transmitted via automated radio or satellite.
- Subject to Revision: If a gauge sensor was partially clogged with silt or experienced electronic drift, hydrologists will later correct or retract the reading during manual review.
- Approved Data: Once audited by agency scientists, readings transition to Approved (qualifier `A`).
Real-time telemetry readings published immediately by monitoring agencies prior to formal scientific review.
What Does Provisional Data Mean?
When you check water levels on WaterLakeLevel or the USGS website, readings from the past several days are routinely tagged with the status Provisional (qualifier `P`).
What This Means for Users:
- Unreviewed Telemetry: The numbers are raw sensor readings transmitted via automated radio or satellite.
- Subject to Revision: If a gauge sensor was partially clogged with silt or experienced electronic drift, hydrologists will later correct or retract the reading during manual review.
- Approved Data: Once audited by agency scientists, readings transition to Approved (qualifier `A`).
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