Storm overflow register · 2025 annual return

Wessex Water storm overflows, 2025

Wessex Water reported 1,346 storm overflows in England for 2025. Together they recorded 24,442 spills over 190,666 hours, an average of 18.2 spills per overflow against 20.4 across England. That ranks 6 of 10 companies, where 1 is the fewest spills per overflow. Counting the same overflows in both years, spills were down 45% on 2024.

220 overflows did not spill · 62 spilled more than 60 times · 1,308 had monitors working for 90% of the year or more · 242 sewage treatment works with overflows

Hours spilling by month, 2025

Hours spilling, all Wessex Water overflows, from the start/stop records. Spills running across a month end are split between the months.

All Wessex Water storm overflows

Sorted by hours spilling. Open an overflow for its permit, location, reasons for high spills and improvement status.

Overflow	Discharges to	Spills 2025	Hours 2025	Spills vs 2024	Monitor uptime
Brickfields Combined Sewer Overflow Overflow on sewer network Company site name WOTTON-UNDER-EDGE BRICKFIELDS EA ID / permit WXW00172 · 102082 Outlet location ST7580992555 (OS grid reference) · View on Apple Maps WFD catchment Ozleworth Bk - source to conf Little Avon R (GB109054026610) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Dyers Brook	0	0.0	no change	100%
Parnell Road CSO Overflow on sewer network Company site name CLEVEDON PARNELL ROAD EA ID / permit WXW00844 · 102296 Outlet location ST4098871164 (OS grid reference) · View on Apple Maps WFD catchment Land Yeo - Yearling Ditch to mouth (GB109052027321) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Land Yeo	0	0.0	no change	100%
Shires Car Park CSO Overflow on sewer network Company site name TROWBRIDGE THE SHIRES MULTI-STOREY CAR PARK/BASEMENT EA ID / permit WXW00990 · 101007 Outlet location ST8473058270 (OS grid reference) · View on Apple Maps WFD catchment Biss (Bitham Bk to Bristol Avon) (GB109053021791) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	River Biss via SWS	0	0.0	no change	100%
Crossways Road CSO Overflow on sewer network Company site name BRISTOL CROSSWAYS ROAD GARDEN R/O NO 114 EA ID / permit WXW00347 · 011283 Outlet location ST6027469895 (OS grid reference) · View on Apple Maps WFD catchment Brislington Bk - source to conf R Avon (Brist) (GB109053021980) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2023) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Trib of Brislington Brook SWS	0	0.0	no change	100%
Monkton Deverill WRC Storm tank at sewage works Sewage works Monkton Deverill Company site name MONKTON DEVERILL HINDON ROAD STORM TANK EA ID / permit WXW00748 · 401861 Outlet location ST8541637249 (OS grid reference) · View on Apple Maps WFD catchment Wylye (Headwaters) (GB108043022520) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2020) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	River Wylye	0	0.0	no change	100%
Wilton Orchard Car Park CSO Overflow on sewer network Company site name TAUNTON WILTON ORCHARD CAR PARK EA ID / permit WXW01262 · EPRJB3797AQ Outlet location ST2253024007 (OS grid reference) · View on Apple Maps WFD catchment Sherford Stream (GB108052015410) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2021) Investigation Env Act (SODRP) investigation ongoing, Operational investigation completed Improvement No improvement action in reporting period	Gaol Stream via SWS	0	0.0	no change	100%
Waldegrave Terrace CSO Overflow on sewer network Company site name RADSTOCK WALEGRAVE TERRACE OPP 9 EA ID / permit WXW01184 · EPRAP3922XM Outlet location ST6950854967 (OS grid reference) · View on Apple Maps WFD catchment Wellow Bk - Snails Bk to Bristol Avon (GB109053022271) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Wellow Brook	0	0.0	no change	100%
Dartmouth Avenue CSO Overflow on sewer network Company site name BATH DARTMOUTH AVE NR ENTRANCE TO LINEAR PARK EA ID / permit WXW00361 · NPSWQD010267 Outlet location ST7340864926 (OS grid reference) · View on Apple Maps WFD catchment Bristol Avon (By Bk to Netham Weir) (GB109053027371) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	The River Avon via SWS	0	0.0	no change	99%
14 Downleaze Road CSO Overflow on sewer network Company site name BRISTOL KINGSWOOD DOWNLEAZE ROAD R/O 14 EA ID / permit WXW00006 · 101643 Outlet location ST6495378410 (OS grid reference) · View on Apple Maps WFD catchment Frome (Brist) - conf Laddon Bk to conf Folly Bk (GB109053027820) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2023) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Trib of River Frome via SWS	0	0.0	no change	100%
Bath Road (No 2) CSO Overflow on sewer network Company site name BRISTOL BATH ROAD JUNCTION FLOWERS HILL EA ID / permit WXW00109 · 100581/CS/01 Outlet location ST6199270650 (OS grid reference) · View on Apple Maps WFD catchment Brislington Bk - source to conf R Avon (Brist) (GB109053021980) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2020) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Brislington Brook via SWS	0	0.0	no change	100%
West Street Combined Sewer Overflow Overflow on sewer network Company site name SOUTH PETHERTON WEST ST O/S 12 EA ID / permit WXW01227 · 102764 Outlet location ST4320716579 (OS grid reference) · View on Apple Maps WFD catchment Lam Brook (GB108052015340) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2023) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Trib of North Mill Brook	0	0.0	no change	100%
Fishponds Storm Retention Tank CSO Overflow on sewer network Company site name BRISTOL FISHPONDS STORM RETENTION TANK EA ID / permit WXW00430 · 101280 Outlet location ST6321075890 (OS grid reference) · View on Apple Maps WFD catchment Frome (Brist) - Bradley Bk to conf Floating Hbr (GB109053027840) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2024) Investigation Operational investigation completed Improvement Operational improvement completed	Fishponds Brook via SWS	0	0.0	no change	100%
Hambrook Quarry Barton Overflow on sewer network EA ID / permit WXW00204 · Unpermitted Outlet location ST6450079500 (OS grid reference) · View on Apple Maps WFD catchment Bradley Bk - conf Stoke Bk to conf R Brist Frome (GB109053027570) 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2024) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Bradley Brook (S)	0	0.0	no change	100%
Bournemouth Seamoor Road O/S 73A Overflow on sewer network EA ID / permit WXW01310 · Permit applied for Outlet location SZ0797589819 (OS grid reference) · View on Apple Maps WFD catchment Dorset / Hampshire (GB620705550000) Bathing water Bournemouth Hengistbury West 2024 spills / hours 0 / 0.0 Long-term average 0.0 spills a year (monitored since 2024) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Poole Bay	0	0.0	no change	100%
Bristol 213 Wellington Hill West BS9 4QL Overflow on sewer network EA ID / permit WXW01324 · Unpermitted Outlet location ST5815777318 (OS grid reference) · View on Apple Maps WFD catchment Trym - source to conf R Avon (Brist) (GB109053027530) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Tributary of the River Trym	0	0.0		100%
Bristol 80 / 82 Kendon Drive BS10 5BT Overflow on sewer network EA ID / permit WXW01325 · Unpermitted Outlet location ST5815777318 (OS grid reference) · View on Apple Maps WFD catchment Trym - source to conf R Avon (Brist) (GB109053027530) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Tributary of the River Trym	0	0.0		100%
Trowbridge - Town Bridge - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01352 · Unpermitted Outlet location ST8472758269 (OS grid reference) · View on Apple Maps WFD catchment Biss (Bitham Bk to Bristol Avon) (GB109053021791) 2024 spills / hours – / – Investigation Operational investigation completed Improvement Operational improvement ongoing	River Biss	0	0.0		100%
Stow House, Shirehampton, Bristol Overflow on sewer network EA ID / permit WXW01350 · Unpermitted Outlet location ST5352476175 (OS grid reference) · View on Apple Maps WFD catchment Not part of a river WB catchment 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	River Avon	0	0.0		100%
Knowle - the Square - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01336 · Unpermitted Outlet location ST6027369894 ST6044569890 (OS grid reference) · View on Apple Maps WFD catchment Brislington Bk - source to conf R Avon (Brist) (GB109053021980) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Brislington Brook	0	0.0		100%
Salisbury - the Close - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01348 · Unpermitted Outlet location SU1512729407 (OS grid reference) · View on Apple Maps WFD catchment Hampshire Avon (Middle) (GB108043015841) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	River Avon	0	0.0		100%
Patchway 83 Callicroft Rd BS34 5BU Overflow on sewer network EA ID / permit WXW01341 · Unpermitted Outlet location ST6067581150 (OS grid reference) · View on Apple Maps WFD catchment Stoke Bk - source to conf Bradley Bk (GB109053027540) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Stoke Brook	0	0.0		100%
Rear Garden 119 Burley Grove BS165QF Overflow on sewer network EA ID / permit WXW01347 · Unpermitted Outlet location ST6597777013 (OS grid reference) · View on Apple Maps WFD catchment Frome (Brist) - conf Laddon Bk to conf Folly Bk (GB109053027820) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Unnamed tributary of the River Frome	0	0.0		100%
Whitelackington - Sewage Treatment Works Inlet overflow at sewage works Sewage works Whitelackington EA ID / permit WXW01356 · Unpermitted Outlet location ST3810715721 (OS grid reference) · View on Apple Maps WFD catchment Isle - Upper to conf Cad Bk (GB108052015190) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Tributary of the River Isle	0	0.0		100%
Bournemouth - Surrey Road - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01318 · Unpermitted Outlet location SZ0776091677 (OS grid reference) · View on Apple Maps WFD catchment Bourne Stream (GB108044009570) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	The Bourne	0	0.0		100%
Bristol - Cave Street / Wilder Street - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01321 · Unpermitted Outlet location ST5953773363 (OS grid reference) · View on Apple Maps WFD catchment Frome (Brist) - Bradley Bk to conf Floating Hbr (GB109053027840) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Floating Harbour	0	0.0		100%
Poole - Albany Park - Sewage Pumping Station Storm discharge at pumping station EA ID / permit WXW01343 · Unpermitted Outlet location SZ0080593076 (OS grid reference) · View on Apple Maps WFD catchment POOLE HARBOUR (GB520804415800) Bathing water Poole Harbour Rockley Sands; Poole Harbour Lake Shellfish water Poole Bay; Poole Harbour North; Poole Harbour South; Poole Harbour West 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Holes Bay	0	0.0		100%
Bristol - Hill Avenue / Marmaduke Street - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01323 · Unpermitted Outlet location ST5930171956 (OS grid reference) · View on Apple Maps WFD catchment BRISTOL AVON (GB530905415405) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	River Avon	0	0.0		100%
Weston-Super-Mare - Locking Road Jnc Birchwood Ave - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01355 · Unpermitted Outlet location ST3055258692 (OS grid reference) · View on Apple Maps WFD catchment Not part of a river WB catchment Bathing water Weston-super-Mare Uphill Slipway; Weston Main 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Axe Estuary(E)	0	0.0		100%
Wookey Hole - 5 West Bank - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01359 · Unpermitted Outlet location ST5313247312 (OS grid reference) · View on Apple Maps WFD catchment Axe - source to Cocklake (GB109052021520) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Trib of River Axe via SWS	0	0.0		100%
Wookey Hole - 3 the Chilterns - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01358 · Unpermitted Outlet location ST5313247312 (OS grid reference) · View on Apple Maps WFD catchment Axe - source to Cocklake (GB109052021520) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Trib of River Axe via SWS	0	0.0		100%
Coultings - Reed Bed - Sewage Treatment Works Inlet overflow at sewage works Sewage works Coultings Reed Bed EA ID / permit WXW01329 · Unpermitted Outlet location ST2298041180 (OS grid reference) · View on Apple Maps WFD catchment Fiddington Brook (GB108052021320) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Moxhill Rhyne	0	0.0		100%
Cucklington - Babwell Road Bioplant - Sewage Treatment Works Inlet overflow at sewage works Sewage works Cucklington Babwell Road Bioplant EA ID / permit WXW01332 · Unpermitted Outlet location ST7544527245 (OS grid reference) · View on Apple Maps WFD catchment Cale (GB108043015850) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Unnamed tributary of the River Cale	–	–		–
Bath - Bathwick Street Adj No. 31 - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01312 · Unpermitted Outlet location ST7531465593 (OS grid reference) · View on Apple Maps WFD catchment Bristol Avon (By Bk to Netham Weir) (GB109053027371) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	River Avon	0	0.0		100%
Shipton Moyne - Sewage Pumping Station Storm discharge at pumping station EA ID / permit WXW01349 · Unpermitted Outlet location ST8917089503 (OS grid reference) · View on Apple Maps WFD catchment Tetbury Avon - unnamed trib to conf Sherston Avon (GB109053027780) 2024 spills / hours – / – Investigation Operational investigation completed Improvement Operational improvement completed	Unnamed tributary of the River Avon	0	0.0		100%
Crewkerne - Opposite 2 Redgate Park - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01330 · Unpermitted Outlet location ST4399511233 (OS grid reference) · View on Apple Maps WFD catchment Merriot Stream (GB108052015290) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Goulds Brook	0	0.0		100%
Poole - Leicester Road / Penn Hill Avenue Junction - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01345 · Unpermitted Outlet location SZ0557291550 (OS grid reference) · View on Apple Maps WFD catchment Not part of a river WB catchment 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Trib of Poole Harbour	0	0.0		100%
Edington - Inmead - Sewage Pumping Station Storm discharge at pumping station EA ID / permit WXW01333 · Unpermitted Outlet location ST9238953425 (OS grid reference) · View on Apple Maps WFD catchment MIlebourne Str - source to conf Semington Bk (GB109053022150) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Milebourne Stream	0	0.0		100%
Trull - Taunton Deane Motorway Services - S105A Sewage Pumping Station Storm discharge at pumping station EA ID / permit WXW01353 · Unpermitted Outlet location ST1948520136 (OS grid reference) · View on Apple Maps WFD catchment Hele Bk (GB108052015400) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Trib of River Tone (S)	0	0.0		99%
o/s Ram Inn Potters Pond W-U-E GL12 7HF Overflow on sewer network EA ID / permit WXW01340 · Unpermitted Outlet location ST7603193269 (OS grid reference) · View on Apple Maps WFD catchment Ozleworth Bk - source to conf Little Avon R (GB109054026610) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Dyers Brook	0	0.0		100%
Bournemouth Belle Vue Road CSO Overflow on sewer network EA ID / permit WXW01320 · Unpermitted Outlet location SZ1586290588 (OS grid reference) · View on Apple Maps WFD catchment Dorset / Hampshire (GB620705550000) Bathing water Bournemouth Hengistbury West 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Poole Bay (C)	0	0.0		100%
Bristol - Chertsey Road - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01322 · Unpermitted Outlet location ST5781574190 (OS grid reference) · View on Apple Maps WFD catchment Frome (Brist) - Bradley Bk to conf Floating Hbr (GB109053027840) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Unnamed tributary of the River Frome	0	0.0		100%
Trowbridge - Bowyers Factory Culvert - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01364 · Unpermitted Outlet location ST8472758269 (OS grid reference) · View on Apple Maps WFD catchment Biss (Bitham Bk to Bristol Avon) (GB109053021791) 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	River Biss	–	–		–
Bristol - York Road - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01362 · Unpermitted Outlet location ST5942371999 (OS grid reference) · View on Apple Maps WFD catchment Not part of a river WB catchment 2024 spills / hours – / – Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	River Avon	–	–		–
Ferndown Dugdell Close Sewage Pumping Station Storm discharge at pumping station EA ID / permit WXW01363 · Unpermitted Outlet location SU0887600619 (OS grid reference) · View on Apple Maps WFD catchment Moors (GB108043011050) 2024 spills / hours – / – Investigation Operational investigation completed Improvement Operational improvement completed	Trib of Moors River	–	–		–
Chippenham - 22 Long Close - Combined Sewer Overflow Overflow on sewer network EA ID / permit WXW01298 · Unpermitted Outlet location ST9288272832 (OS grid reference) · View on Apple Maps WFD catchment Avon (Brist) conf R Marden to conf Semington Bk (GB109053027440) 2024 spills / hours – / – Long-term average 0.0 spills a year (monitored since 2024) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	River Avon via SWS	0	0.0		100%
Home Farm Sewage Pumping Station Storm discharge at pumping station Company site name ALDERBURY - HOME FARM SPS EA ID / permit WXW00560 · 041885 Outlet location SU1760026850 (OS grid reference) · View on Apple Maps WFD catchment Hampshire Avon (Lower) (GB108043015840) 2024 spills / hours – / – Long-term average 0.0 spills a year (monitored since 2024) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period	Tributary of River Avon (S)	0	0.0		100%

Sewage treatment works

Storm tanks and inlet overflows at each Wessex Water sewage works. The figures are 2025 spills.

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