Measuring Authorities

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 AuthorityRegion AbbreviationRegion


NINorthern Ireland
EACLCumbria and Lancashire
EADCDevon, Cornwall and the Isles of Scilly
EAEAEast Anglia
EAEMEast Midlands
EAGMMCGreater Manchester, Merseyside and Cheshire
EAHNLHertfordshire and North London
EAKSLKent, South London and East Sussex
EALNLincolnshire and Northamptonshire
EANENorth East
EASSDSolent and South Downs
EAWMWest Midlands
NRWWales NNorth Wales
NRWWales SSouth Wales
NRWWales SWSouth West Wales
SEPASEPA NNorth Scotland
SEPASEPA EEast Scotland
SEPASEPA SSouth Scotland

Measuring Authority Contact Points:

Primary Measuring Authorities

NRFA CodeMeasuring AuthorityHeadquarters
EAEnvironment AgencyBristol
NRWNatural Resources Wales (Cyfoeth Naturiol Cymru)Cardiff
SEPAScottish Environment Protection AgencyStirling
DfIRDeparment for Infrastructure - RiversCookstown

Other Measuring Authorities

NRFA CodeMeasuring AuthorityHeadquarters
CRTCanal & River TrustMilton Keynes
CEHUK Centre for Ecology & HydrologyWallingford
ESWEssex & Suffolk Water plcChelmsford
GSNIGeological Survey of Northern IrelandBelfast
DOENINorthern Ireland Environment AgencyLisburn (Water Management Unit)
NEWNorthumbrian Water LimitedDurham
SWAScottish WaterDunfermline
SWSouthern WaterWorthing
NWWUnited UtilitiesWarrington
YWYorkshire WaterBradford