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
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
STUBDEN/IRE 06/01/2026 Stubden Beck
THORNTON MOOR/IRE 06/01/2026 Stubden beck
LOWER LAITHE/IRE 13/01/2026 Sladen Beck
LEEMING/IRE 22/01/2026 Leeming Water
LEESHAW/IRE 22/01/2026 Dunkirk Beck
BARDEN LOWER/IRE 03/02/2026 Embsay Beck
ELDWICK/IRE 12/02/2026 Eldwick Beck
GRAINCLIFFE/IRE 12/02/2026 Eldwick Beck
EMBSAY/IRE 26/02/2026 Embsay Beck
SILSDEN/IRE 26/02/2026 Silsden Beck
REVA/IRE 03/03/2026 Jum Beck
WEECHER/IRE 03/03/2026 Gill Beck
PONDEN/IRE 05/03/2026 River Woorth
HEWENDEN/IRE 19/03/2026 Hewenden Beck
GILSTEAD/ESR 24/03/2026 Little Beck
ELSLACK/IRE 21/04/2026 Elslack Beck
WHINNY GILL/IRE 21/04/2026 Little Brook
DOE PARK/IRE 07/05/2026 Denholme Beck
EMBSAY/IRE 16/06/2026 Embsay Beck
WATER SHEDDLES/IRE 18/06/2026 River Worth
LOWER LAITHE/IRE 07/07/2026 Sladen Beck
LEEMING/IRE 21/07/2026 Leeming Water
LEESHAW/IRE 21/07/2026 Dunkirk Beck
KEIGHLEY MOOR/IRE 23/07/2026 Morkin Beck
SILSDEN/IRE 13/08/2026 Silsden Beck
THORNTON MOOR/IRE 01/09/2026 Stubden beck
STUBDEN/IRE 03/09/2026 Stubden Beck
HEWENDEN/IRE 24/09/2026 Hewenden Beck
ELDWICK/IRE 29/09/2026 Eldwick Beck
GRAINCLIFFE/IRE 29/09/2026 Eldwick Beck
ELSLACK/IRE 01/10/2026 Elslack Beck
WHINNY GILL/IRE 01/10/2026 Little Brook
REVA/IRE 06/10/2026 Jum Beck
WEECHER/IRE 06/10/2026 Gill Beck
DOE PARK/IRE 08/10/2026 Denholme Beck
GILSTEAD/ESR 22/10/2026 Little Beck
PONDEN/IRE 03/11/2026 River Woorth
WATER SHEDDLES/IRE 03/12/2026 River Worth
KEIGHLEY MOOR/IRE 08/12/2026 Morkin Beck
FARNLEY STORM/SLK 22/04/2026 Wortley Beck
FARNLEY STORM/SLK 04/11/2026 Wortley Beck

 

Calder
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
GORPLE LOWER/IRE 20/01/2026 Hebden Stream
GORPLE UPPER/IRE 20/01/2026 Gorple lower
MIXENDEN/IRE 27/01/2026 Hebble Brook
OGDEN/IRE 27/01/2026 Hebble Brook
WALSHAW DEAN MIDDLE/IRE 29/01/2026 Walshaw lower
RYBURN/IRE 05/02/2026 River Ryburn
WALSHAW DEAN UPPER/IRE 19/02/2026 Walshaw middle
WHITLEY/ESR 10/03/2026 Whitley wood
GORPLEY/IRE 02/04/2026 Gorpley Clough
BAITINGS/IRE 07/04/2026 River Ryburn
WITHENS CLOUGH/IRE 09/04/2026 Turvin Clough
ALBERT/ESR 21/04/2026 To Sewer
RAMSDEN WOOD/ESR 21/04/2026 BrownHill IRE
BOOTH WOOD/IRE 23/04/2026 Booth Dean Clough
DEANHEAD/IRE 02/06/2026 Black Burne Brook
SCAMMONDEN/IRE 02/06/2026 Black Brook
RINGSTONE/IRE 04/06/2026 Butts Clough
GREEN WITHENS/IRE 09/06/2026 Booth Dean Clough
SPA CLOUGH/ESR 09/06/2026 Booth Dean Upper IRE
ARDSLEY/ESR 11/06/2026 Haigh moor beck
WALSHAW DEAN LOWER/IRE 18/06/2026 Hebden Stream
DEAN HEAD LOWER/IRE 23/06/2026 Luddenden Dean
DEAN HEAD UPPER/IRE 23/06/2026 Luddenden Dean
WARLEY MOOR/IRE 23/06/2026 Deanhead upper
WIDDOP/IRE 25/06/2026 Hebden Stream
RYBURN/IRE 16/07/2026 River Ryburn
MIXENDEN/IRE 21/07/2026 Hebble Brook
OGDEN/IRE 21/07/2026 Hebble Brook
GORPLE LOWER/IRE 25/08/2026 Hebden Stream
GORPLE UPPER/IRE 25/08/2026 Gorple lower
WALSHAW DEAN MIDDLE/IRE 27/08/2026 Walshaw lower
WALSHAW DEAN UPPER/IRE 27/08/2026 Walshaw middle
BOOTH WOOD/IRE 03/09/2026 Booth Dean Clough
WHITLEY/ESR 08/09/2026 Whitley wood
BAITINGS/IRE 10/09/2026 River Ryburn
ARDSLEY/ESR 29/09/2026 Haigh moor beck
GORPLEY/IRE 01/10/2026 Gorpley Clough
DEANHEAD/IRE 13/10/2026 Black Burne Brook
SCAMMONDEN/IRE 13/10/2026 Black Brook
ALBERT/ESR 15/10/2026 To Sewer
RAMSDEN WOOD/ESR 15/10/2026 BrownHill IRE
WITHENS CLOUGH/IRE 29/10/2026 Turvin Clough
RINGSTONE/IRE 19/11/2026 Butts Clough
DEAN HEAD LOWER/IRE 03/12/2026 Luddenden Dean
DEAN HEAD UPPER/IRE 03/12/2026 Luddenden Dean
WARLEY MOOR/IRE 03/12/2026 Deanhead upper
WIDDOP/IRE 08/12/2026 Hebden Stream
GREEN WITHENS/IRE 10/12/2026 Booth Dean Clough
SPA CLOUGH/ESR 10/12/2026 Booth Dean Upper IRE
WALSHAW DEAN LOWER/IRE 15/12/2026 Hebden Stream
Colne & Holme
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
BLAKELEY/IRE 08/01/2026 Butterely IRE
BOSHAW WHAMS/IRE 29/01/2026 Upper house dyke
HOLMESTYES/IRE 29/01/2026 River Ribble
BILBERRY/IRE 03/02/2026 Digley Reservoir
DIGLEY/IRE 03/02/2026 Digley Brook
BUTTERLEY/IRE 10/02/2026 Wessenden Brook
WESSENDEN HEAD/IRE 12/02/2026 Wessenden Brook
WESSENDEN OLD/IRE 12/02/2026 None
LONGWOOD COMP/IRE 17/02/2026 Longwood Brook
LONGWOOD/ESR 17/02/2026 Longwood Brook
RIDING WOOD/IRE 19/02/2026 Ramsden IRE
YATEHOLME/IRE 19/02/2026 Netherley Clough
BROWNHILL/IRE 17/03/2026 River Holme
RAMSDEN/IRE 17/03/2026 To Sewer
BLACKMOORFOOT/IRE (NORTH) 17/03/2026 Brow Grains Dyke
BLACKMOORFOOT/IRE (SOUTH) 17/03/2026 Hoyle House Clough
DEERHILL/IRE 24/03/2026 Bradley Brook
SNAILSDEN/IRE 11/06/2026 Harden Dike
BLAKELEY/IRE 16/06/2026 Butterely IRE
BUTTERLEY/IRE 16/06/2026 Wessenden Brook
RIDING WOOD/IRE 06/08/2026 Ramsden IRE
YATEHOLME/IRE 06/08/2026 Netherley Clough
WESSENDEN HEAD/IRE 13/08/2026 Wessenden Brook
WESSENDEN OLD/IRE 13/08/2026 None
BOSHAW WHAMS/IRE 18/08/2026 Upper house dyke
HOLMESTYES/IRE 18/08/2026 River Ribble
BILBERRY/IRE 17/09/2026 Digley Reservoir
DIGLEY/IRE 17/09/2026 Digley Brook
LONGWOOD COMP/IRE 22/10/2026 Longwood Brook
LONGWOOD/ESR 22/10/2026 Longwood Brook
BLACKMOORFOOT/IRE (NORTH) 03/11/2026 Brow Grains Dyke
BLACKMOORFOOT/IRE (SOUTH) 03/11/2026 Hoyle House Clough
DEERHILL/IRE 03/11/2026 Bradley Brook
BROWNHILL/IRE 12/11/2026 River Holme
RAMSDEN/IRE 12/11/2026 To Sewer
SNAILSDEN/IRE 10/12/2026 Harden Dike
Derwent
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
ELVINGTON/NO 1 ESR 09/03/2026 Pumping Station
ELVINGTON/NO 2 ESR 09/03/2026 0
ELVINGTON/NO 3 ESR 09/03/2026 0
LOFTSOME BRIDGE/ESR 12/03/2026 River Derwent
TOPHILL LOW/NO 1 ESR 19/05/2026 Barmsten Drain
TOPHILL LOW/NO 2 ESR 19/05/2026 Barmsten Drain
ELVINGTON/NO 1 ESR 15/09/2026 Pumping Station
ELVINGTON/NO 2 ESR 15/09/2026 0
ELVINGTON/NO 3 ESR 15/09/2026 0
LOFTSOME BRIDGE/ESR 06/10/2026 River Derwent
TOPHILL LOW/NO 1 ESR 17/11/2026 Barmsten Drain
TOPHILL LOW/NO 2 ESR 17/11/2026 Barmsten Drain
Don
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
BROADSTONES/ESR 06/01/2026 Broastones Dike
MIDHOPE/IRE 27/01/2026 Hagg Brook
WINDLEDEN LOWER/IRE 03/02/2026 Clough Beck
WINDLEDEN UPPER/IRE 03/02/2026 Windleden Lower
RIVELIN UPPER/IRE 05/02/2026 Rivelin Lower IRE
RIVELIN/DEP POND IRE 05/02/2026 River Rivelin
REDMIRES MIDDLE/IRE 10/02/2026 None
REDMIRES UPPER/IRE 10/02/2026 None
REDMIRES LOWER/IRE 12/02/2026 None
INGBIRCHWORTH/IRE 26/02/2026 Ingbirchworth Dike
MOREHALL/IRE 03/03/2026 Ewden Beck
DALE DIKE/IRE 10/03/2026 River Loxley
DAMFLASK/IRE 17/03/2026 River Loxley
ROYD MOOR/IRE 24/03/2026 River Don
SCOUT DIKE/IRE 26/03/2026 River Don
STRINES/IRE 02/04/2026 Dale Dike IRE
WINSCAR/IRE 12/05/2026 River Don
UNDERBANK/IRE 20/05/2026 Little Don River
LANGSETT/IRE 21/05/2026 Little Don River
BROADSTONES/ESR 21/05/2026 Broastones Dike
AGDEN/IRE 26/05/2026 Agden beck
RIVELIN LOWER/IRE 04/06/2026 River Rivelin
HARDEN/IRE 11/06/2026 Winscar IRE
INGBIRCHWORTH/IRE 18/06/2026 Ingbirchworth Dike
BROOMHEAD/IRE 25/06/2026 Morehall IRE
MIDHOPE/IRE 21/07/2026 Hagg Brook
RIVELIN UPPER/IRE 04/08/2026 Rivelin Lower IRE
RIVELIN/DEP POND IRE 04/08/2026 River Rivelin
REDMIRES LOWER/IRE 11/08/2026 None
REDMIRES MIDDLE/IRE 11/08/2026 None
REDMIRES UPPER/IRE 11/08/2026 None
WINDLEDEN LOWER/IRE 27/08/2026 Clough Beck
WINDLEDEN UPPER/IRE 27/08/2026 Windleden Lower
MOREHALL/IRE 03/09/2026 Ewden Beck
DAMFLASK/IRE 22/09/2026 River Loxley
DALE DIKE/IRE 24/09/2026 River Loxley
SCOUT DIKE/IRE 29/09/2026 River Don
STRINES/IRE 01/10/2026 Dale Dike IRE
WINSCAR/IRE 08/10/2026 River Don
UNDERBANK/IRE 15/10/2026 Little Don River
ROYD MOOR/IRE 29/10/2026 River Don
AGDEN/IRE 05/11/2026 Agden beck
RIVELIN LOWER/IRE 24/11/2026 River Rivelin
BROOMHEAD/IRE 03/12/2026 Morehall IRE
LANGSETT/IRE 08/12/2026 Little Don River
HARDEN/IRE 10/12/2026 Winscar IRE
Esk
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
RANDYMERE/ESR 06/01/2026 0
RANDYMERE/ESR 14/07/2026 0

 

Hull
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
BRANSHOLME/SLK 23/01/2026 To Sewer
BRANSHOLME/SLK 23/07/2026 To Sewer

 

Nidd
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
ANGRAM/IRE 05/02/2026 NONE
SCAR HOUSE/IRE 05/02/2026 River Nidd
GOUTHWAITE/IRE 10/03/2026 River Nidd
JOHN O GAUNTS/IRE 07/04/2026 Oakdale Beck
SCARGILL/IRE 07/04/2026 Oakdale Beck
GOUTHWAITE/IRE 08/09/2026 River Nidd
ANGRAM/IRE 15/09/2026 NONE
SCAR HOUSE/IRE 15/09/2026 River Nidd
JOHN O GAUNTS/IRE 22/10/2026 Oakdale Beck
SCARGILL/IRE 22/10/2026 Oakdale Beck
Ouse
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
CLIFTON LAKE/SLK 26/03/2026 Blue Beck
CLIFTON LAKE/SLK 24/09/2026 Blue Beck

 

Swale
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
THORNTON STEWARD/ESR 10/03/2026 Finghall Beck
COD BECK/IRE 14/05/2026 Cod Beck
THORNTON STEWARD/ESR 27/10/2026 Finghall Beck
COD BECK/IRE 29/10/2026 Cod Beck
Ure
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
LEIGHTON/IRE 26/03/2026 River Burn
LUMLEY MOOR/IRE 23/04/2026 Holborn Beck
ROUNDHILL/IRE 04/06/2026 LEIGHTON IRE
LUMLEY MOOR/IRE 12/11/2026 Holborn Beck
LEIGHTON/IRE 01/12/2026 River Burn
ROUNDHILL/IRE 01/12/2026 LEIGHTON IRE
Wharfe & Washburn
RESERVOIR DATE NAME OF WATERCOURSE AFFECTED
FEWSTON/IRE 06/01/2026 SWINSTY IRE
CHELKER/IRE 08/01/2026 Bank Gill Beck
MARCH GHYLL/IRE 20/01/2026 Bow Beck
GRIMWITH/IRE 24/02/2026 River Dibb/Wharfe
ECCUP/ESR 26/02/2026 Eccup Beck
CARR BOTTOM/IRE 10/03/2026 WOODHEAD BECK
PANORAMA/IRE 10/03/2026 Black Beck
LINDLEY WOOD/IRE 12/03/2026 River Washburn
THRUSCROSS/IRE 07/05/2026 River Washburn
SWINSTY/IRE 21/05/2026 River Washburn
FEWSTON/IRE 21/05/2026 SWINSTY IRE
CHELKER/IRE 16/06/2026 Bank Gill Beck
BARDEN UPPER/IRE 23/06/2026 Barden Beck
MARCH GHYLL/IRE 16/07/2026 Bow Beck
BARDEN LOWER/IRE 18/08/2026 Barden Beck
LINDLEY WOOD/IRE 08/09/2026 River Washburn
CARR BOTTOM/IRE 17/09/2026 WOODHEAD BECK
PANORAMA/IRE 17/09/2026 Black Beck
GRIMWITH/IRE 22/09/2026 River Dibb/Wharfe
ECCUP/ESR 10/11/2026 Eccup Beck
BARDEN UPPER/IRE 10/12/2026 Barden Beck
THRUSCROSS/IRE 10/12/2026 River Washburn
SWINSTY/IRE 15/12/2026 River Washburn