64001 - Dyfi at Dyfi Bridge

Grid Reference:	23 (SH) 745 019
Operator:	EA
Catchment Area:	471.3 km²
Level of Station:	5.9 mOD
Max. Altitude:	907.0 mOD
Mean flow:	23.15 m³s^-1
95% exceedance (Q95):	2.177 m³s^-1
10% exceedance (Q10):	54.09 m³s^-1
61-90 Av. Ann. Rainfall:	1834 mm

Sample Hydrograph of Gauged Daily Flows

Flow Duration Curve for Gauged Daily Flows

Station Description

A 40m wide river section controlled by the invert and arches of the historical Dyfi road bridge d/s. A good stable section although records in early years are marred by substantial engineering works carried out on the bridge. Natural regime.

Catchment Description

Geology: impermeable Silurian formations, minor Boulder Clay and alluvium deposits. Catchment is 60% grassland and 30% forested, with patches of upland heath.

Factors Affecting Runoff

Natural to within 10% at the 95 percentile flow.

River Flow and Catchment Rainfall on the National River Flow Archive

Gauged Daily Flows (gdf):	1962 to 2006
Naturalised Monthly Flows (nmf):	1965 to 1966
Monthly Catchment Rainfall (rnf):	1962 to 2006

Datatype	1960s										1970s										1980s										1990s										2000s

gdf
nmf
rnf

For many stations monthly peak flows are also archived. When daily flow data are not available monthly mean flows may be held on the National River Flow Archive. See Data Holdings for further information.

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