148,859
Observations
1,750
Series
1,750
Subjects
1874–2025
Period covered

Methodology

Annual mean discharge as published by the USGS statistics service, computed by USGS from its own quality-controlled daily record. Hydrionis does not recompute the mean; it converts cubic feet per second to cubic metres per second — a foot being exactly 0.3048 m, the conversion is exact — and records the publisher’s unit alongside so a value can be checked against the source. Sites are selected per state because the USGS site service does not accept a national query, and a site is kept only where the published statistics themselves span fifty years, which is a stricter test than the period of record advertised in the site listing.

What this dataset cannot tell you

Coverage

SubjectsUnited States streamgauges opening before 1930 with 50+ years of published statistics1,750 held
Period18742025
Unitsm³/s
Update cadenceAnnually
Identifierus-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

Rights and access

Licence position

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

  • Applies to material authored by US federal agencies. Third-party material carried within a federal product may be separately protected.

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), United States River Flow Dataset, version 1.0.0. Retrieved from https://hydrionis.com/data/datasets/us-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, and the first Hydrionis dataset outside the United Kingdom drawn from station-level measurement.

Additions

  • Annual mean flow for 1,751 long-record United States gauges.

Getting the data

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