255,737
Observations
711
Series
356
Subjects
1879–2026
Period covered

Methodology

Daily mean flows are read from the Environment Agency Hydrology Data Explorer and aggregated by Hydrionis to monthly means, then to annual means from those monthly values rather than from daily values directly — averaging days would weight a year toward its best-observed months. A month is published only where readings covering at least 80% of its days passed the Environment Agency’s quality control; readings flagged Suspect, Missing or Unchecked are excluded and counted. Only stations whose record opens before 1970 are ingested, because the value of this dataset is depth of history.

What this dataset cannot tell you

Coverage

SubjectsEnglish gauging stations with a record opening before 1970356 held
Period18792026
Unitsm³/s
Update cadenceMonthly
Identifierengland-river-flow v1.0.0

Every metric this dataset carries, with the unit it is stored in and the geography level it is reported at. Full definitions are in the data dictionary.

IdentifierFieldUnitReported at
river-flow-meanMean river flow
Average volumetric discharge past a gauging station over a stated period.
m³/sriver-gauge
river-flow-monthly-meanMean monthly river flow
Average volumetric discharge past a gauging station over a calendar month.
m³/sriver-gauge

Rights and access

Licence position

Open with attribution. Derivative use true; redistribution true; commercial reuse true.

Attribution required:

  • Contains public sector information licensed under the Open Government Licence v3.0.

Permitted uses

  • Public display
  • Derived analysis
  • API delivery
  • Bulk download
  • Commercial use

Available to: Public, Developer, Research, Professional, Enterprise. These follow from the rights of the contributing publishers, not from a Hydrionis pricing decision — no access tier can widen what a publisher withheld.

Contributing sources

Suggested citation

Hydrionis (2026), England River Flow Dataset, version 1.0.0. Retrieved from https://hydrionis.com/data/datasets/england-river-flow/

Cite the version. Hydrionis datasets change as publishers release and as methods are revised, and a citation without a version cannot be checked later.

Changelog

Version 1.0.0 — 2026-08-24

First release.

Additions

  • Monthly and annual mean flow for 356 long-record English gauging stations.

Getting the data

Machine-readable metadata for this dataset is at /api/v1/datasets/england-river-flow.json. For bulk extracts, higher-volume access or commercial licensing, see data enquiries.