Data Types and Formats

NRFA Data Types

The core NRFA data types are listed below. Users should note that not all data types are available for all sites. Individual station information pages on this website provide details of what data are available for each gauging station.

VariableNRFA Code
Gauged Daily FlowsGDF
Gauged Monthly FlowsGMF
Naturalised Daily Flows (where available)NDF
Naturalised Monthly Flows (where available)NMF
Gauged Daily RunoffGDR
Gauged Monthly RunoffGMR
Naturalised Daily Runoff (where available)NDR
Naturalised Monthly Runoff (where available)NMR
Annual Maximum FlowAMAX
Peaks Over ThresholdPOT
Catchment Monthly RainfallCMR
Catchment Daily RainfallCDR

Users should note the following points which are consistent across data types:

  • All river flows are in cubic metres per second (abbreviated to m3s-1 and also referred to as 'cumecs')
  • All catchment rainfall is given as total rainfall in millimetres (mm) across the catchment in the given period of reference
  • Runoff is expressed in millimetres (mm) and is the notional depth of water over the catchment. 

Click here for further details of NRFA data holdings.

NRFA Data Formats

Time series data files are available either for direct download from this website or via the manual enquiries/retrievals service. Click here for more information about manual enquiries/retrievals. 

Data is normally provided in a comma separated (csv) format, comprising of a header block containing important information about the gauging station followed by the time series requested. The data are presented in two or three columns:

  1. The date in the format YYYY-MM-DD
  2. The variable value. If the variable for a particular day/month is missing then no value will be given.
  3. A quoted single character flag, which may have one of the following values. Where there is no flag there will be only two columns.
    • "M" Missing (flow column will be blank).
    • "E" Estimated

Note: AMAX and POT data are currently only available in WINFAP-FEH format.