Scour test schedule

Scour tests must be routinely carried out on reservoirs to make sure they can be lowered in an emergency.

View over Baitings Reservoir

A scour test involves slowly opening and closing the outlet valve, which causes the release of water into the stream. This is likely to cause increased turbulence and deterioration of water quality immediately downstream for the duration of the test and for a short while after.

On the day, tests generally commence between 7-10am and may last for up to 4 hours in total, with a release at full flow rate for about half an hour. If you might be affected by a particular test, please check a week beforehand as there is a small chance for test dates to be moved to a later date or for additional tests to be required.

Aire

Upper & Middle Aire
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
LOWER LAITHE/IRE 14-Jan-21 Sladen Beck
THORNTON MOOR/IRE 19-Jan-21 Stubden Beck
STUBDEN/IRE 21-Jan-21 Stubden Beck
LEEMING/IRE 26-Jan-21 Leeming Water
LEESHAW/IRE 26-Jan-21 Dunkirk Beck
KEIGHLEY MOOR/IRE 04-Feb-21 Morkin Beck
FARNLEY STORM/SLK 16-Feb-21 Wortley Beck
PONDEN/IRE 18-Feb-21 River Worth
EMBSAY/IRE 23-Feb-21 Embsay Beck
WEECHER/IRE 04-Mar-21 Gill Beck
SILSDEN/IRE 18-Mar-21 Silsden Beck
HEWENDEN/IRE 30-Mar-21 Hewenden Beck
GRAINCLIFFE/IRE 01-Apr-21 Eldwick Beck
WATER SHEDDLES/IRE 01-Apr-21 River Worth
ELDWICK/IRE 06-Apr-21 Eldwick Beck
ELSLACK/IRE 08-Apr-21 Elslack Beck
WHINNY GILL/IRE 13-Apr-21 Little Brook
REVA/IRE 04-May-21 Jum Beck
DOE PARK/IRE 11-May-21 Denholme Beck
EMBSAY/IRE 15-Apr-21 Embsay Beck
GILSTEAD/ESR 03-Jun-21 Little Beck
LOWER LAITHE/IRE 08-Jul-21 Sladen Beck
LEEMING/IRE 22-Jul-21 Leeming Water
LEESHAW/IRE 22-Jul-21 Dunkirk Beck
THORNTON MOOR/IRE 03-Aug-21 Stubden Beck
STUBDEN/IRE 05-Aug-21 Stubden Beck
KEIGHLEY MOOR/IRE 10-Aug-21 Morkin Beck
WEECHER/IRE 24-Aug-21 Gill Beck
EMBSAY/IRE 26-Aug-21 Embsay Beck
HEWENDEN/IRE 28-Sep-21 Hewenden Beck
WHINNY GILL/IRE 05-Oct-21 Little Brook
REVA/IRE 07-Oct-21 Jum Beck
ELDWICK/IRE 12-Oct-21 Eldwick Beck
WATER SHEDDLES/IRE 14-Oct-21 River Worth
GRAINCLIFFE/IRE 14-Oct-21 Eldwick Beck
ELSLACK/IRE 19-Oct-21 Elslack Beck
PONDEN/IRE 19-Oct-21 River Worth
DOE PARK/IRE 04-Nov-21 Denholme Beck
GILSTEAD/ESR 09-Nov-21 Little Beck
KEIGHLEY MOOR/IRE 09-Nov-21 Morkin Beck
SILSDEN/IRE 16-Nov-21 Silsden Beck

Calder

Upper Calder
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
WALSHAW DEAN LOWER/IRE 02-Feb-21 Hebden Stream
WALSHAW DEAN MIDDLE/IRE 02-Feb-21 Walshaw Dean Lower
WALSHAW DEAN UPPER/IRE 03-Feb-21 Walshaw Dean Middle
WALSHAW DEAN LOWER/IRE 02-Mar-21 Hebden Stream
WALSHAW DEAN MIDDLE/IRE 02-Mar-21 Walshaw Dean Lower
WALSHAW DEAN UPPER/IRE 02-Mar-21 Walshaw Dean Middle
GORPLE LOWER/IRE 16-Mar-21 Hebden Stream
GORPLE UPPER/IRE 16-Mar-21 Gorple Lower
GORPLEY/IRE 01-Apr-21 Gorpley Clough
WIDDOP/IRE 22-Apr-21 Hebden Stream
GORPLE LOWER/IRE 26-Aug-21 Hebden Stream
GORPLE UPPER/IRE 26-Aug-21 Gorple Lower
WALSHAW DEAN LOWER/IRE 21-Sep-21 Hebden Stream
WALSHAW DEAN MIDDLE/IRE 21-Sep-21 Walshaw Dean Lower
WALSHAW DEAN UPPER/IRE 21-Sep-21 Walshaw Dean Middle
GORPLEY/IRE 05-Oct-21 Gorpley Clough
WIDDOP/IRE 05-Oct-21 Hebden Stream
Middle Calder
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
MIXENDEN/IRE 28-Jan-21 Hebble Brook
OGDEN/IRE 28-Jan-21 Hebble Brook
WITHENS CLOUGH/IRE 23-Feb-21 Turvin Clough
DEANHEAD/IRE 25-Feb-21 Black Burne Brook
SCAMMONDEN/IRE 25-Feb-21 Black Brook
ALBERT/ESR 09-Mar-21 To Sewer
RAMSDEN WOOD/ESR 09-Mar-21 To Sewer
RYBURN/IRE 18-Mar-21 River Ryburn
CASTLE CARR 30-Mar-21 Luddenden Dean
DEAN HEAD LOWER/IRE 30-Mar-21 Luddenden Dean
DEAN HEAD UPPER/IRE 30-Mar-21 Luddenden Dean
WARLEY MOOR/IRE 30-Mar-21 Deanhead Upper
BAITINGS/IRE 06-Apr-21 River Ryburn
GREEN WITHENS/IRE 15-Apr-21 Booth Dean
SPA CLOUGH/ESR 15-Apr-21 Spa Clough
BOOTH DEAN LOWER/IRE 27-Apr-21 Boothwood IRE
BOOTH DEAN UPPER/IRE 27-Apr-21 Boothdean Lower IRE
BOOTH WOOD/IRE 27-Apr-21 Booth Dean Clough
RINGSTONE/IRE 20-May-21 Butts Clough
MIXENDEN/IRE 03-Aug-21 Hebble Brook
OGDEN/IRE 03-Aug-21 Hebble Brook
BOOTH WOOD/IRE 19-Aug-21 Booth Dean Clough
RYBURN/IRE 02-Sep-21 River Ryburn
GREEN WITHENS/IRE 23-Sep-21 Booth Dean
SPA CLOUGH/ESR 23-Sep-21 Spa Clough
BOOTH DEAN LOWER/IRE 28-Sep-21 Boothwood IRE
BOOTH DEAN UPPER/IRE 28-Sep-21 Boothdean Lower IRE
BOOTH WOOD/IRE 28-Sep-21 Booth Dean Clough
BAITINGS/IRE 07-Oct-21 River Ryburn
CASTLE CARR 12-Oct-21 Luddenden Dean
DEAN HEAD LOWER/IRE 12-Oct-21 Luddenden Dean
DEAN HEAD UPPER/IRE 12-Oct-21 Luddenden Dean
WARLEY MOOR/IRE 12-Oct-21 Deanhead Upper
DEANHEAD/IRE 14-Oct-21 Black Burne Brook
SCAMMONDEN/IRE 14-Oct-21 Black Brook
ALBERT/ESR 19-Oct-21 To Sewer
RAMSDEN WOOD/ESR 19-Oct-21 To Sewer
WITHENS CLOUGH/IRE 02-Nov-21 Turvin Clough
RINGSTONE/IRE 23-Nov-21 Butts Clough
Lower Calder
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
WHITLEY/ESR 25-Mar-21 Whitley Wood
ARDSLEY/ESR 10-Jun-21 Haigh Moor Beck
WHITLEY/ESR 21-Oct-21 Whitley Wood
ARDSLEY/ESR 11-Nov-21 Haigh Moor Beck

Colne & Holme

Colne & Holme
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
BLAKELEY/IRE 05-Jan-21 Butterley IRE
WESSENDEN OLD/IRE 05-Jan-21 Blakeley IRE
HOLMESTYES/IRE 21-Jan-21 River Ribble
BOSHAW WHAMS/IRE 21-Jan-21 Upper House Dyke
LONGWOOD COMP/IRE 18-Feb-21 Longwood Brook
LONGWOOD/ESR 18-Feb-21 Longwood Brook
RIDING WOOD/IRE 23-Feb-21 Ramsden IRE
YATEHOLME/IRE 23-Feb-21 Netherley Clough
DIGLEY/IRE 25-Feb-21 Digley Brook
BILBERRY/IRE 25-Feb-21 Digley IRE
BROWNHILL/IRE 02-Mar-21 River Holme
BLACKMOORFOOT/IRE (NORTH SIDE) 04-Mar-21 Brow Grains Dyke
BLACKMOORFOOT/IRE (SOUTH SIDE) 04-Mar-21 Hoyle House Clough
DEERHILL/IRE 04-Mar-21 Bradley Brook
BUTTERLEY/IRE 11-Mar-21 Wessenden Brook
RAMSDEN/IRE 25-May-21 Brownhill IRE
SNAILSDEN/IRE 27-May-21 Harden Beck
COLDERS/IRE 27-May-21 None
WESSENDEN HEAD/IRE 27-May-21 Wessenden Brook
WESSENDEN OLD/IRE 17-Jun-21 Blakeley IRE
BLAKELEY/IRE 22-Jul-21 Butterley IRE
BLACKMOORFOOT/IRE (SOUTH SIDE) 29-Jul-21 Hoyle House Clough
BOSHAW WHAMS/IRE 19-Aug-21 Upper House Dyke
HOLMESTYES/IRE 19-Aug-21 River Ribble
WESSENDEN OLD/IRE 19-Oct-21 Blakeley IRE
LONGWOOD COMP/IRE 26-Oct-21 Longwood Brook
LONGWOOD/ESR 26-Oct-21 Longwood Brook
RIDING WOOD/IRE 28-Oct-21 Ramsden IRE
YATEHOLME/IRE 28-Oct-21 Netherley Clough
BLACKMOORFOOT/IRE (NORTH SIDE) 04-Nov-21 Brow Grains Dyke
BLACKMOORFOOT/IRE (SOUTH SIDE) 04-Nov-21 Hoyle House Clough
DEERHILL/IRE 04-Nov-21 Bradley Brook
DIGLEY/IRE 04-Nov-21 Digley Brook
BILBERRY/IRE 04-Nov-21 Digley IRE
BUTTERLEY/IRE 11-Nov-21 Wessenden Brook
BROWNHILL/IRE 16-Nov-21 River Holme
RAMSDEN/IRE 16-Nov-21 Brownhill IRE
COLDERS/IRE 25-Nov-21 None
WESSENDEN HEAD/IRE 25-Nov-21 Wessenden Brook
SNAILSDEN/IRE 02-Dec-21 Harden Beck

Derwent

Middle & Lower Derwent
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
ELVINGTON/NO 1 ESR 22-Dec-20 River Derwent
ELVINGTON/NO 2 ESR 22-Dec-20 River Derwent
ELVINGTON/NO 3 ESR 22-Dec-20 River Derwent
ELVINGTON/NO 1 ESR 10-Mar-21 River Derwent
LOFTSOME BRIDGE/ESR 13-May-21 River Derwent
TOPHILL LOW/NO 1 ESR 19-May-21 River Hull
TOPHILL LOW/NO 2 ESR 19-May-21 Barmston Drain
ELVINGTON/NO 1 ESR 22-Sep-21 River Derwent
LOFTSOME BRIDGE/ESR 11-Nov-21 River Derwent
TOPHILL LOW/NO 1 ESR 17-Nov-21 River Hull
TOPHILL LOW/NO 2 ESR 17-Nov-21 Barmston Drain

Don

Upper Don
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
BROADSTONES/ESR 07-Jan-21 Broadstones Dike
AGDEN/IRE 21-Jan-21 Agden Beck
DALE DIKE/IRE 26-Jan-21 River Loxley
RIVELIN LOWER/IRE 28-Jan-21 River Rivelin
DAMFLASK/IRE 04-Feb-21 River Loxley
REDMIRES LOWER/IRE 11-Feb-21 Wyming Brook
REDMIRES MIDDLE/IRE 11-Feb-21 Redmires Lower IRE
REDMIRES UPPER/IRE 11-Feb-21 Redmires Middle IRE
RIVELIN UPPER/IRE 11-Feb-21 Rivelin Lower IRE
RIVELIN/DEP POND IRE 11-Feb-21 River Rivelin
UNDERBANK/IRE 18-Feb-21 River Little Don
INGBIRCHWORTH/IRE 09-Mar-21 Ingbirchworth Dike
SCOUT DIKE/IRE 11-Mar-21 River Don
STRINES/IRE 01-Apr-21 Dale Dike IRE
MIDHOPE/IRE 03-Jun-21 River Little Don
ROYD MOOR/IRE 29-Apr-21 River Don
WINDLEDEN LOWER/IRE 04-May-21 Clough Beck
WINDLEDEN UPPER/IRE 04-May-21 Windleden Lower IRE
WINSCAR/IRE 13-May-21 River Don
HARDEN/IRE 27-May-21 Winscar IRE
LANGSETT/IRE 01-Jun-21 River Little Don
MOREHALL/IRE 13-Apr-21 Ewden Beck
BROOMHEAD/IRE 6-May-21 Morehall IRE
BROADSTONES/ESR 17-Jun-21 Broadstones Dike
AGDEN/IRE 22-Jul-21 Agden Beck
DALE DIKE/IRE 27-Jul-21 River Loxley
RIVELIN LOWER/IRE 29-Jul-21 River Rivelin
DAMFLASK/IRE 03-Aug-21 River Loxley
RIVELIN UPPER/IRE 05-Aug-21 Rivelin Lower IRE
RIVELIN/DEP POND IRE 05-Aug-21 River Rivelin
REDMIRES LOWER/IRE 12-Aug-21 Wyming Brook
REDMIRES MIDDLE/IRE 12-Aug-21 Redmires Lower IRE
REDMIRES UPPER/IRE 12-Aug-21 Redmires Middle IRE
WINSCAR/IRE 05-Oct-21 River Don
STRINES/IRE 05-Oct-21 Dale Dike IRE
MIDHOPE/IRE 25-Nov-21 River Little Don
UNDERBANK/IRE 19-Oct-21 River Little Don
ROYD MOOR/IRE 02-Nov-21 River Don
INGBIRCHWORTH/IRE 09-Nov-21 Ingbirchworth Dike
SCOUT DIKE/IRE 11-Nov-21 River Don
WINDLEDEN LOWER/IRE 18-Nov-21 Clough Beck
WINDLEDEN UPPER/IRE 18-Nov-21 Windleden Lower IRE
MOREHALL/IRE 12-Oct-21 Ewden Beck
HARDEN/IRE 02-Dec-21 Winscar IRE
BROOMHEAD/IRE 07-Dec-21 Morehall IRE
LANGSETT/IRE 09-Dec-21 River Little Don

Esk

Esk
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
RANDY MERE/ESR 16-Jun-21 Oakley Beck
RANDY MERE/ESR 08-Dec-21 Oakley Beck

Hull

Lower Hull
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
BRANSHOLME/SLK 19-Jan-21 River Hull
BRANSHOLME/SLK 21-Jul-21 River Hull

Nidd

Nidd
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
SCARGILL/IRE 14-Jan-21 Oak Beck
GOUTHWAITE/IRE 25-Feb-21 River Nidd
SCAR HOUSE/IRE 09-Mar-21 River Nidd
SCARGILL/IRE 08-Apr-21 Oak Beck
JOHN O GAUNTS/IRE 08-Apr-21 Oak Beck
GOUTHWAITE/IRE 29-Jul-21 River Nidd
SCAR HOUSE/IRE 02-Sep-21 River Nidd
JOHN O GAUNTS/IRE 23-Nov-21 Oak Beck
SCARGILL/IRE 23-Nov-21 Oak Beck

Ouse

Upper Ouse
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
CLIFTON LAKE/SLK 16-Sep-21 Drain

Swale

Middle & Lower Swale
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
COD BECK/IRE 09-Feb-21 Cod Beck
THORNTON STEWARD/ESR 11-Mar-21 Finghall Beck
COD BECK/IRE 11-May-21 Cod Beck
THORNTON STEWARD/ESR 28-Oct-21 Finghall Beck
COD BECK/IRE 02-Nov-21 Cod Beck

Ure

Middle & Lower Ure
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
LUMLEY MOOR/IRE 18-Feb-21 Holborn Beck
LEIGHTON/IRE 01-Apr-21 River Burn
ROUNDHILL/IRE 06-Apr-21 Leighton IRE
LEIGHTON/IRE 28-Sep-21 River Burn
ROUNDHILL/IRE 28-Sep-21 Leighton IRE
LUMLEY MOOR/IRE 16-Nov-21 Holborn Beck

Wharfe & Washburn

Upper Wharfe
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
ANGRAM/IRE 09-Mar-21 Scar House IRE
GRIMWITH/IRE 16-Mar-21 River Dibb
ANGRAM/IRE 02-Sep-21 Scar House IRE
GRIMWITH/IRE 04-Nov-21 River Dibb
Middle Wharfe & Washburn
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
BARDEN LOWER/IRE 05-Jan-21 Barden Beck
CHELKER/IRE 07-Jan-21 Bank Gill Beck
FEWSTON/IRE 07-Jan-21 Swinsty IRE
BARDEN UPPER/IRE 12-Jan-21 Barden Beck
MARCH GHYLL/IRE 21-Jan-21 Bow Beck
THRUSCROSS/IRE 04-Feb-21 River Washburn
ECCUP/ESR 02-Mar-21 Eccup Beck, Harewood Estate Ponds, River Wharfe
SWINSTY/IRE 04-Mar-21 River Washburn
LINDLEY WOOD/IRE 25-Mar-21 River Washburn
CARR BOTTOM/IRE 01-Apr-21 Carr Beck
PANORAMA/IRE 06-Apr-21 Black Beck
BARDEN LOWER/IRE 24-Jun-21 Barden Beck
BARDEN UPPER/IRE 29-Jun-21 Barden Beck
CHELKER/IRE 01-Jul-21 Bank Gill Beck
MARCH GHYLL/IRE 22-Jul-21 Bow Beck
FEWSTON/IRE 22-Jul-21 Swinsty IRE
SWINSTY/IRE 02-Sep-21 River Washburn
THRUSCROSS/IRE 16-Sep-21 River Washburn
CARR BOTTOM/IRE 21-Sep-21 Carr Beck
PANORAMA/IRE 23-Sep-21 Black Beck
ECCUP/ESR 09-Nov-21 Eccup Beck, Harewood Estate Ponds, River Wharfe
LINDLEY WOOD/IRE 09-Dec-21 River Washburn