What the data can tell us
Provisional readings, incomplete coverage and the boundaries of this atlas.
Observations, not forecasts
Station readings record measurements at a point in time. They are not flood forecasts and do not describe the full river or its surrounding catchment. This website is an independent atlas, not an official warning service.
Provisional source data
Observations may be delayed, missing or revised. Source quality and error fields are retained by the data pipeline; this atlas does not invent meanings for undocumented source flags. Always consult the official source when a reading matters.
An incomplete view
The atlas is built from verified catalogue entries and available published observations. A missing station, reading or assessment is a gap in this website’s coverage. It is not evidence that a river is dry, unmonitored or in a particular condition.
Longer records need care
When older daily summaries are available, they are calculated from the readings collected by this project. Coverage can be incomplete. These summaries are not official OPW daily means and should not be treated as a complete historical record.
Keep the sources close
Official source links are included on river and station pages. Use the original publisher for its latest information, terms, context and any corrections. This atlas does not replace professional advice or official warnings.