National River Flow Archive

Licence

NRFA click-through licence for API access

Commercial reuse

Yes

Redistribution

No

Derivative use

No

Attribution required

Yes

Data from the UK National River Flow Archive

Restrictions

Clause 3.1 prohibits making the data available for download from any internet site without prior agreement. Clause 3.5 permits only temporary caching of a limited volume, for no more than 30 calendar days, and prohibits manipulating or aggregating the data. Clause 4.1 requires the data to be held confidential. Redistribution and derivative publication therefore require prior written agreement with UKCEH.

Terms last checked

24 August 2026

Publisher

UK Centre for Ecology and Hydrology

Website

https://nrfa.ceh.ac.uk/

API

https://nrfaapps.ceh.ac.uk/nrfa/ws

Geographic coverage

United Kingdom — ~1,500 gauging stations

Temporal coverage

1853 onwards

Update frequency

daily

Formats

csv, json, api

Bulk download

Available

Registration required

No

Cost to Hydrionis

Free

Domains

river flow, drought

Assessed for ingestion on 24 August 2026 and rejected. The NRFA is the best river-flow archive in the UK and its API is technically excellent, but the click-through licence governing API access is incompatible with how Hydrionis works. Clause 3.1 forbids making the data available for download from any internet site; clause 3.5 permits caching only a limited volume, temporarily, for no more than 30 days, and forbids aggregating it; clause 4.1 imposes a confidentiality undertaking. Hydrionis is a statically exported site that commits every value it holds to a public repository and serves it permanently as JSON and CSV — which is precisely what those clauses prohibit. This is the case spec §4 warns about: publicly accessible is not the same as reusable. The Environment Agency hydrology API carries much of the same measurement under OGL v3 and is used instead.