| Grid Reference: | 44 (SE) 422 473 |
| Operator: | EA |
| Local number: | 8912004 |
| Catchment Area: | 758.9 km2 |
| Level of Station: | 13.7 mOD |
| Max. Altitude: | 704.0 mOD |
Broad-crested masonry weir 47m wide; c/m cableway originally 1.5km u/s then moved to new ultrasonic station at Tadcaster in 1990. Insensitive at low flows. Does not drown at high flows, though small amount of bypassing on the right bank. Level data: 1936-1955. Recalibration (from 1965) completed but flows reprocessed from 1982 only. Pre-1965 data less reliable. Mill race opened in early 1990s (not rated) so flows not reliable. Regulation effect of headwater reservoirs evident at low flows. Small net export of water (inc. Bradford supply).
Mixed geology of moderate permeability - mainly Carboniferous Limestone, grits and Coal Measures with over 40% superficial deposits. Predominantly mixed rural catchment, 60% grassland, with moorland headwaters.
For further information see the Explanatory Notes.
Long term hydrograph (A4 PDF)
Long term data file (csv - comma separated value format)