The Measuring Authority is the organisation responsible for the provision of river flow data to the National River Flow Archive.
Responsibility for the collection and processing of hydrometric data in the UK rests primarily with the Measuring Authorities who operate the river flow monitoring network. The principle Measuring Authorities in each of the component parts of the UK are: the Environment Agency (EA) in England, Natural Resources Wales (NRW) in Wales, the Scottish Environment Protection Agency (SEPA) in Scotland and for Northern Ireland, the Department for Infrastructure - Rivers (DfIR). Additional flow measurement is carried out by a variety of public and private bodies and research organisations (including CEH). The Environment Agency, NRW and SEPA areas are subdivided into regions (see map below).
| Measuring Authority | Region Abbreviation | Region |
|---|---|---|
DfIR | NI | Northern Ireland |
| EA | CL | Cumbria and Lancashire |
| EA | DC | Devon, Cornwall and the Isles of Scilly |
| EA | EA | East Anglia |
| EA | EM | East Midlands |
| EA | GMMC | Greater Manchester, Merseyside and Cheshire |
| EA | HNL | Hertfordshire and North London |
| EA | KSL | Kent, South London and East Sussex |
| EA | LN | Lincolnshire and Northamptonshire |
| EA | NE | North East |
| EA | SSD | Solent and South Downs |
| EA | T | Thames |
| EA | WM | West Midlands |
| EA | WX | Wessex |
| EA | Y | Yorkshire |
| NRW | Wales N | North Wales |
| NRW | Wales S | South Wales |
| NRW | Wales SW | South West Wales |
| SEPA | SEPA N | North Scotland |
| SEPA | SEPA E | East Scotland |
| SEPA | SEPA S | South Scotland |
