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 | 02/01/2025 | Stubden Beck |
EMBSAY/IRE | 07/01/2025 | Embsay Beck |
LOWER LAITHE/IRE | 14/01/2025 | Sladen Beck |
THORNTON MOOR/IRE | 16/01/2025 | Stubden Beck |
LEESHAW/IRE | 23/01/2025 | Dunkirk Beck |
LEEMING/IRE | 23/01/2025 | Leeming Water |
GILSTEAD/ESR | 11/02/2025 | Little Beck |
GRAINCLIFFE/IRE | 13/02/2025 | Eldwick Beck |
ELDWICK/IRE | 13/02/2025 | Eldwick Beck |
SILSDEN/IRE | 27/02/2025 | Silsden Beck |
WEECHER/IRE | 04/03/2025 | Gill Beck |
REVA/IRE | 04/03/2025 | Jum Beck |
PONDEN/IRE | 06/03/2025 | River Worth |
HEWENDEN/IRE | 20/03/2025 | Hewenden Beck |
BLACKMOORFOOT/IRE | 20/03/2025 | Embsay Beck |
WHINNY GILL/IRE | 22/04/2025 | Little Brook |
ELSLACK/IRE | 22/04/2025 | Elslack Beck |
DOE PARK/IRE | 08/05/2025 | Denholme Beck |
EMBSAY/IRE | 17/06/2025 | Embsay Beck |
WATER SHEDDLES/IRE | 19/06/2025 | River Worth |
LOWER LAITHE/IRE | 08/07/2025 | Sladen Beck |
LEESHAW/IRE | 22/07/2025 | Dunkirk Beck |
LEEMING/IRE | 22/07/2025 | Leeming Water |
KEIGHLEY MOOR/IRE | 24/07/2025 | Morkin Beck |
SILSDEN/IRE | 14/08/2025 | Silsden Beck |
THORNTON MOOR/IRE | 04/09/2025 | Stubden Beck |
STUBDEN/IRE | 04/09/2025 | Stubden Beck |
HEWENDEN/IRE | 25/09/2025 | Hewenden Beck |
DOE PARK/IRE | 25/09/2025 | Denholme Beck |
GRAINCLIFFE/IRE | 30/09/2025 | Eldwick Beck |
ELDWICK/IRE | 30/09/2025 | Eldwick Beck |
WHINNY GILL/IRE | 02/10/2025 | Little Brook |
ELSLACK/IRE | 02/10/2025 | Elslack Beck |
WEECHER/IRE | 07/10/2025 | Gill Beck |
REVA/IRE | 07/10/2025 | Jum Beck |
PONDEN/IRE | 16/10/2025 | River Worth |
GILSTEAD/ESR | 23/10/2025 | Little Beck |
WATER SHEDDLES/IRE | 04/12/2025 | River Worth |
KEIGHLEY MOOR/IRE | 09/12/2025 | Morkin Beck |
FARNLEY STORM/SLK | 23/04/2025 | Wortley Beck |
FARNLEY STORM/SLK | 05/11/2025 | Wortley Beck |
Upper Calder
RESERVOIR | DATE | NAME OF WATERCOURSE AFFECTED |
---|---|---|
WALSHAW DEAN LOWER/IRE | 07/01/2025 | Hebden Stream |
GORPLE UPPER/IRE | 21/01/2025 | Gorple Lower |
GORPLE LOWER/IRE | 21/01/2025 | Hebden Stream |
WALSHAW DEAN UPPER/IRE | 30/01/2025 | Walshaw Dean Middle |
WALSHAW DEAN MIDDLE/IRE | 30/01/2025 | Walshaw Dean Lower |
GORPLEY/IRE | 03/04/2025 | Gorpley Clough |
WALSHAW DEAN LOWER/IRE | 19/06/2025 | Hebden Stream |
WIDDOP/IRE | 26/06/2025 | Hebden Stream |
GORPLE UPPER/IRE | 26/08/2025 | Gorple Lower |
GORPLE LOWER/IRE | 26/08/2025 | Hebden Stream |
WALSHAW DEAN UPPER/IRE | 28/08/2025 | Walshaw Dean Middle |
WALSHAW DEAN MIDDLE/IRE | 28/08/2025 | Walshaw Dean Lower |
GORPLEY/IRE | 02/10/2025 | Gorpley Clough |
WIDDOP/IRE | 09/12/2025 | Hebden Stream |
WALSHAW DEAN LOWER/IRE | 16/12/2025 | Hebden Stream |
Middle Calder
RESERVOIR | DATE | NAME OF WATERCOURSE AFFECTED |
---|---|---|
OGDEN/IRE | 28/01/2025 | Hebble Brook |
MIXENDEN/IRE | 28/01/2025 | Hebble Brook |
RYBURN/IRE | 06/02/2025 | River Ryburn |
SCAMMONDEN/IRE | 25/02/2025 | Black Brook |
DEANHEAD/IRE | 25/02/2025 | Black Burne Brook |
RAMSDEN WOOD/ESR | 06/03/2025 | To Sewer |
ALBERT/ESR | 06/03/2025 | To Sewer |
BAITINGS/IRE | 08/04/2025 | River Ryburn |
WITHENS CLOUGH/IRE | 10/04/2025 | Turvin Clough |
BOOTH WOOD/IRE | 24/04/2025 | Booth Dean Clough |
RINGSTONE/IRE | 05/06/2025 | Butts Clough |
SPA CLOUGH/ESR | 10/06/2025 | Spa Clough |
GREEN WITHENS/IRE | 10/06/2025 | Booth Dean |
WARLEY MOOR/IRE | 24/06/2025 | Deanhead Upper |
DEAN HEAD UPPER/IRE | 24/06/2025 | Luddenden Dean |
DEAN HEAD LOWER/IRE | 24/06/2025 | Luddenden Dean |
OGDEN/IRE | 22/07/2025 | Hebble Brook |
MIXENDEN/IRE | 22/07/2025 | Hebble Brook |
RYBURN/IRE | 31/07/2025 | River Ryburn |
BOOTH WOOD/IRE | 11/09/2025 | Booth Dean Clough |
BAITINGS/IRE | 11/09/2025 | River Ryburn |
SCAMMONDEN/IRE | 14/10/2025 | Black Brook |
DEANHEAD/IRE | 14/10/2025 | Black Burne Brook |
RAMSDEN WOOD/ESR | 16/10/2025 | To Sewer |
ALBERT/ESR | 16/10/2025 | To Sewer |
WITHENS CLOUGH/IRE | 30/10/2025 | Turvin Clough |
RINGSTONE/IRE | 20/11/2025 | Butts Clough |
WARLEY MOOR/IRE | 04/12/2025 | Deanhead Upper |
DEAN HEAD UPPER/IRE | 04/12/2025 | Luddenden Dean |
DEAN HEAD LOWER/IRE | 04/12/2025 | Luddenden Dean |
SPA CLOUGH/ESR | 11/12/2025 | Spa Clough |
GREEN WITHENS/IRE | 11/12/2025 | Booth Dean |
Lower Calder
RESERVOIR | DATE | NAME OF WATERCOURSE AFFECTED |
---|---|---|
WHITLEY/ESR | 13/03/2025 | Whitley Wood |
ARDSLEY/ESR | 29/04/2025 | Haigh Moor Beck |
WHITLEY/ESR | 09/09/2025 | Whitley Wood |
ARDSLEY/ESR | 30/09/2025 | Haigh Moor Beck |
Colne & Holme
RESERVOIR | DATE | NAME OF WATERCOURSE AFFECTED |
BUTTERLEY/IRE | 09/01/2025 | Wessenden Brook |
BLAKELEY/IRE | 09/01/2025 | Butterley IRE |
HOLMESTYES/IRE | 30/01/2025 | River Ribble |
BOSHAW WHAMS/IRE | 30/01/2025 | Upper House Dyke |
DIGLEY/IRE | 04/02/2025 | Digley Brook |
BILBERRY/IRE | 04/02/2025 | Digley IRE |
WESSENDEN OLD/IRE | 13/02/2025 | Blakeley IRE |
WESSENDEN HEAD/IRE | 13/02/2025 | Wessenden Brook |
LONGWOOD/ESR | 18/02/2025 | Longwood Brook |
LONGWOOD COMP/IRE | 18/02/2025 | Longwood Brook |
YATEHOLME/IRE | 20/02/2025 | Netherley Clough |
RIDING WOOD/IRE | 20/02/2025 | Ramsden IRE |
RAMSDEN/IRE | 18/03/2025 | Brownhill IRE |
BROWNHILL/IRE | 18/03/2025 | River Holme |
DEERHILL/IRE | 20/03/2025 | Bradley Brook |
SNAILSDEN/IRE | 12/06/2025 | Harden Beck |
BUTTERLEY/IRE | 17/06/2025 | Wessenden Brook |
BLAKELEY/IRE | 17/06/2025 | Butterley IRE |
YATEHOLME/IRE | 07/08/2025 | Netherley Clough |
RIDING WOOD/IRE | 07/08/2025 | Ramsden IRE |
WESSENDEN OLD/IRE | 14/08/2025 | Blakeley IRE |
WESSENDEN HEAD/IRE | 14/08/2025 | Wessenden Brook |
HOLMESTYES/IRE | 19/08/2025 | River Ribble |
BOSHAW WHAMS/IRE | 19/08/2025 | Upper House Dyke |
DIGLEY/IRE | 18/09/2025 | Digley Brook |
BILBERRY/IRE | 18/09/2025 | Digley IRE |
LONGWOOD/ESR | 23/10/2025 | Longwood Brook |
LONGWOOD COMP/IRE | 23/10/2025 | Longwood Brook |
DEERHILL/IRE | 04/11/2025 | Bradley Brook |
RAMSDEN/IRE | 13/11/2025 | Brownhill IRE |
BROWNHILL/IRE | 13/11/2025 | River Holme |
SNAILSDEN/IRE | 11/12/2025 | Harden Beck |
Derwent
RESERVOIR | DATE | NAME OF WATERCOURSE AFFECTED |
---|---|---|
ELVINGTON/NO 1 ESR | 11/03/2025 | River Derwent |
ELVINGTON/NO 2 ESR | 11/03/2025 | River Derwent |
ELVINGTON/NO 3 ESR | 11/03/2025 | River Derwent |
LOFTSOME BRIDGE/ESR | 12/03/2025 | River Derwent |
TOPHILL LOW/NO 1 ESR | 20/05/2025 | River Hull |
TOPHILL LOW/NO 2 ESR | 20/05/2025 | Barmston Drain |
ELVINGTON/NO 1 ESR | 16/09/2025 | River Derwent |
ELVINGTON/NO 2 ESR | 16/09/2025 | River Derwent |
ELVINGTON/NO 3 ESR | 16/09/2025 | River Derwent |
LOFTSOME BRIDGE/ESR | 07/10/2025 | River Derwent |
TOPHILL LOW/NO 1 ESR | 18/11/2025 | River Hull |
TOPHILL LOW/NO 2 ESR | 18/11/2025 | Barmston Drain |
Upper Don
RESERVOIR | DATE | NAME OF WATERCOURSE AFFECTED |
---|---|---|
BROADSTONES/ESR | 07/01/2025 | Broadstones Dike |
MIDHOPE/IRE | 28/01/2025 | River Little Don |
INGBIRCHWORTH/IRE | 28/01/2025 | Ingbirchworth Dike |
RIVELIN/DEP POND IRE | 06/02/2025 | River Rivelin |
RIVELIN UPPER/IRE | 06/02/2025 | Rivelin Lower IRE |
REDMIRES UPPER/IRE | 11/02/2025 | Redmires Middle IRE |
REDMIRES MIDDLE/IRE | 11/02/2025 | Redmires Lower IRE |
REDMIRES LOWER/IRE | 11/02/2025 | Wyming Brook |
UNDERBANK/IRE | 18/02/2025 | River Little Don |
MOREHALL/IRE | 04/03/2025 | Ewden Beck |
AGDEN/IRE | 05/03/2025 | Agden Beck |
DAMFLASK/IRE | 06/03/2025 | River Loxley |
DALE DIKE/IRE | 06/03/2025 | River Loxley |
SCOUT DIKE/IRE | 25/03/2025 | River Don |
ROYD MOOR/IRE | 25/03/2025 | River Don |
STRINES/IRE | 03/04/2025 | Dale Dike IRE |
WINDLEDEN UPPER/IRE | 01/05/2025 | Windleden Lower IRE |
WINDLEDEN LOWER/IRE | 01/05/2025 | Clough Beck |
WINSCAR/IRE | 13/05/2025 | River Don |
RIVELIN LOWER/IRE | 05/06/2025 | River Rivelin |
LANGSETT/IRE | 10/06/2025 | River Little Don |
HARDEN/IRE | 12/06/2025 | Winscar IRE |
BROADSTONES/ESR | 17/06/2025 | Broadstones Dike |
INGBIRCHWORTH/IRE | 19/06/2025 | Ingbirchworth Dike |
BROOMHEAD/IRE | 26/06/2025 | Morehall IRE |
MIDHOPE/IRE | 22/07/2025 | River Little Don |
RIVELIN/DEP POND IRE | 05/08/2025 | River Rivelin |
RIVELIN UPPER/IRE | 05/08/2025 | Rivelin Lower IRE |
REDMIRES UPPER/IRE | 12/08/2025 | Redmires Middle IRE |
REDMIRES MIDDLE/IRE | 12/08/2025 | Redmires Lower IRE |
REDMIRES LOWER/IRE | 12/08/2025 | Wyming Brook |
MOREHALL/IRE | 04/09/2025 | Ewden Beck |
DAMFLASK/IRE | 23/09/2025 | River Loxley |
DALE DIKE/IRE | 25/09/2025 | River Loxley |
STRINES/IRE | 02/10/2025 | Dale Dike IRE |
WINSCAR/IRE | 09/10/2025 | River Don |
UNDERBANK/IRE | 16/10/2025 | River Little Don |
WINDLEDEN UPPER/IRE | 28/10/2025 | Windleden Lower IRE |
WINDLEDEN LOWER/IRE | 28/10/2025 | Clough Beck |
ROYD MOOR/IRE | 30/10/2025 | River Don |
AGDEN/IRE | 06/11/2025 | Agden Beck |
SCOUT DIKE/IRE | 11/11/2025 | River Don |
RIVELIN LOWER/IRE | 25/11/2025 | River Rivelin |
BROOMHEAD/IRE | 04/12/2025 | Morehall IRE |
LANGSETT/IRE | 09/12/2025 | River Little Don |
HARDEN/IRE | 11/12/2025 | Winscar IRE |
Nidd
RESERVOIR | DATE | NAME OF WATERCOURSE AFFECTED |
---|---|---|
SCAR HOUSE/IRE | 06/02/2025 | River Nidd |
ANGRAM/IRE | 06/02/2025 | Scar House IRE |
GOUTHWAITE/IRE | 11/03/2025 | River Nidd |
SCARGILL/IRE | 08/04/2025 | Oak Beck |
JOHN O GAUNTS/IRE | 08/04/2025 | Oak Beck |
GOUTHWAITE/IRE | 09/09/2025 | River Nidd |
SCAR HOUSE/IRE | 16/09/2025 | River Nidd |
ANGRAM/IRE | 16/09/2025 | Scar House IRE |
SCARGILL/IRE | 23/10/2025 | Oak Beck |
JOHN O GAUNTS/IRE | 23/10/2025 | Oak Beck |
Wharfe & Washburn
RESERVOIR | DATE | NAME OF WATERCOURSE AFFECTED |
---|---|---|
FEWSTON/IRE | 07/01/2025 | Swinsty IRE |
CHELKER/IRE | 07/01/2025 | Bank Gill Beck |
MARCH GHYLL/IRE | 21/01/2025 | Bow Beck |
BARDEN LOWER/IRE | 04/02/2025 | Barden Beck |
PANORAMA/IRE | 18/02/2025 | Black Beck |
CARR BOTTOM/IRE | 18/02/2025 | Carr Beck |
GRIMWITH/IRE | 25/02/2025 | River Dibb |
ECCUP/ESR | 27/02/2025 | Eccup Beck, Harewood Estate Ponds, River Wharfe |
SWINSTY/IRE | 22/05/2025 | River Washburn |
THRUSCROSS/IRE | 10/06/2025 | River Washburn |
CHELKER/IRE | 17/06/2025 | Bank Gill Beck |
LINDLEY WOOD/IRE | 19/06/2025 | River Washburn |
BARDEN UPPER/IRE | 24/06/2025 | Barden Beck |
MARCH GHYLL/IRE | 17/07/2025 | Bow Beck |
FEWSTON/IRE | 22/07/2025 | Swinsty IRE |
BARDEN LOWER/IRE | 19/08/2025 | Barden Beck |
GRIMWITH/IRE | 11/09/2025 | River Dibb |
PANORAMA/IRE | 18/09/2025 | Black Beck |
CARR BOTTOM/IRE | 18/09/2025 | Carr Beck |
ECCUP/ESR | 06/11/2025 | Eccup Beck, Harewood Estate Ponds, River Wharfe |
LINDLEY WOOD/IRE | 09/12/2025 | River Washburn |
THRUSCROSS/IRE | 11/12/2025 | River Washburn |
BARDEN UPPER/IRE | 11/12/2025 | Barden Beck |
SWINSTY/IRE | 16/12/2025 | River Washburn |