Storm overflow register · 2025 annual return

Southern Water storm overflows, 2025

Southern Water reported 977 storm overflows in England for 2025. Together they recorded 15,554 spills over 114,868 hours, an average of 15.9 spills per overflow against 20.4 across England. That ranks 4 of 10 companies, where 1 is the fewest spills per overflow. Counting the same overflows in both years, spills were down 47% on 2024.

175 overflows did not spill · 42 spilled more than 60 times · 862 had monitors working for 90% of the year or more · 215 sewage treatment works with overflows

Hours spilling by month, 2025

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

All Southern 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
Sandgate Pumping Station Storm discharge at pumping station Company site name GRANVILLE PARADE SANDGATE CEO - 108642 EA ID / permit SWS00736 · A00719 Outlet location TR2046035070 (OS grid reference) · View on Apple Maps WFD catchment Kent South (GB640704540001) Bathing water Folkestone; Sandgate 2024 spills / hours 4 / 5.4 Long-term average 4.7 spills a year (monitored since 2016) Investigation Bathing Water and/or Shellfish Water investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 1.7 hours spilling →	Controlled Sea	1	1.7	down 75%	100%
St Andrews Road Portsmouth CSO Overflow on sewer network Company site name ST ANDREWS ROAD PORTSMOUTH CSO - 108474 EA ID / permit SWS00807 · A01277 Outlet location SU6874005590 (OS grid reference) · View on Apple Maps WFD catchment LANGSTONE HARBOUR (GB580705130000) Shellfish water Langstone Harbour 2024 spills / hours 5 / 1.4 Long-term average 15.2 spills a year (monitored since 2016) Investigation UWWTR investigation ongoing Improvement Env Act (SODRP) improvement ongoing, Bathing Water and/or Shellfish Water improvement ongoing Volume & pollution Estimate from 1.7 hours spilling →	Broom Channel	3	1.7	down 40%	100%
Ashton Corner Ceo Storm discharge at pumping station Company site name ASHTON CORNER CEO - 108898 EA ID / permit SWS00029 · A01399 Outlet location SU5397018190 (OS grid reference) · View on Apple Maps WFD catchment Upper Hamble (GB107042016280) 2024 spills / hours 0 / 0.0 Long-term average 1.7 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.7 hours spilling →	Tributary of the River Hamble	1	1.7	up from 0	100%
Station Street Lymington NO1 CSO Overflow on sewer network Company site name STATION STREET LYMINGTON NO 1 CSO - 102640 EA ID / permit SWS00829 · A00361 Outlet location SZ3273096000 (OS grid reference) · View on Apple Maps WFD catchment LYMINGTON (GB520704202100) Shellfish water Lymington and Sowley; Pennington 2024 spills / hours 0 / 0.0 Long-term average 5.3 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.7 hours spilling →	Lymington River	3	1.7	up from 0	100%
Seaford Bay Outfall Inlet overflow at sewage works Sewage works Seaford Bay Outfall Company site name BEACH ROAD NEWHAVEN STORM TANK CSO - 108083 EA ID / permit SWS00754 · A00014 Outlet location TQ4500000760 (OS grid reference) · View on Apple Maps WFD catchment OUSE (GB540704104900) Bathing water Seaford 2024 spills / hours 6 / 19 Long-term average 5.0 spills a year (monitored since 2019) Monitor below 90% Sensor failure / issue · Resolved - May Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.7 hours spilling →	Tidal River Ouse	1	1.7	down 83%	42%
Mill Lane Shalfleet Wps Storm discharge at pumping station Company site name MILL LANE SHALFLEET CEO - 108556 EA ID / permit SWS00572 · W00190 Outlet location SZ4150089420 (OS grid reference) · View on Apple Maps WFD catchment Caul Bourne (GB107101006020) Shellfish water Lymington and Sowley; Newtown; Yarmouth 2024 spills / hours 1 / 0.5 Long-term average 9.7 spills a year (monitored since 2016) Investigation Env Act (SODRP) investigation ongoing, UWWTR investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 1.6 hours spilling →	Newtown River	1	1.6	no change	100%
Colwell Chine CSO Storm discharge at pumping station Company site name COLWELL CHINE CEO - 107407 EA ID / permit SWS00193 · A00725 Outlet location SZ3271087870 (OS grid reference) · View on Apple Maps WFD catchment Solent (GB650705150000) Bathing water Colwell Bay; Totland Bay Shellfish water Pennington; Yarmouth 2024 spills / hours 3 / 14 Long-term average 2.6 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.6 hours spilling →	The Solent	2	1.6	down 33%	100%
Ashey Road CSO Overflow on sewer network Company site name ASHEY ROAD RYDE CSO - 102336 EA ID / permit SWS00025 · A00769 Outlet location SZ5896090810 (OS grid reference) · View on Apple Maps WFD catchment Monktonmead Brook (GB107101006120) Bathing water Ryde Shellfish water Cowes and Medina; Ryde 2024 spills / hours 5 / 1.6 Long-term average 2.3 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.6 hours spilling →	Monktonmead Brook	4	1.6	down 20%	100%
Manor Way Swanscombe Ceo Storm discharge at pumping station Company site name MANOR WAY SWANSCOMBE CEO - 108020 EA ID / permit SWS00545 · NPSWQD001831 Outlet location TQ6040075270 (OS grid reference) · View on Apple Maps WFD catchment Ebbsfleet (GB106040024190) 2024 spills / hours 1 / 2.1 Long-term average 0.4 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.6 hours spilling →	Unnamed Trib of River Thames	1	1.6	no change	100%
Terminus Road Cowes CSO Overflow on sewer network Company site name TERMINUS ROAD COWES CSO - 108563 EA ID / permit SWS00857 · A02509 Outlet location SZ4976096140 (OS grid reference) · View on Apple Maps WFD catchment Solent (GB650705150000) Bathing water Cowes; Gurnard Shellfish water Central Solent; Cowes and Medina; Spithead and Stokes Bay; Stanswood Bay 2024 spills / hours 3 / 2.4 Long-term average 62.3 spills a year (monitored since 2016) Investigation UWWTR investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 1.5 hours spilling →	The Solent	5	1.5	up 67%	100%
Alderbrook Way CSO Overflow on sewer network Company site name ALDERBROOK WAY CROWBOROUGH NO 2 CSO - 116052 EA ID / permit SWS00010 · A00897 Outlet location TQ5219028750 (OS grid reference) · View on Apple Maps WFD catchment Tributary of upper Medway at Crowborough (GB106040013360) 2024 spills / hours 9 / 7.9 Long-term average 6.5 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.5 hours spilling →	Jarvis Brook	3	1.5	down 67%	100%
Barton Road Dover Storm Tank CSO Overflow on sewer network Company site name BARTON ROAD DOVER STORM TANK CSO - 107652 EA ID / permit SWS00045 · A00717 Outlet location TR3142042180 (OS grid reference) · View on Apple Maps WFD catchment Dour from Kearsney to Dover (GB107040073310) 2024 spills / hours 0 / 0.0 Long-term average 0.8 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.5 hours spilling →	River Dour	1	1.5	up from 0	100%
High St Gravesend Outside 70 CSO Overflow on sewer network Company site name HIGH STREET GRAVESEND OUTSIDE 70 CSO - 108651 EA ID / permit SWS00424 · CASM.1319 Outlet location TQ6481074510 (OS grid reference) · View on Apple Maps WFD catchment THAMES MIDDLE (GB530603911402) 2024 spills / hours 45 / 99 Long-term average 13.5 spills a year (monitored since 2016) Monitor below 90% Sensor failure / issue · Resolved - Sep Investigation UWWTR investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 1.4 hours spilling →	River Thames Estuary	8	1.4	down 82%	82%
Wicor Mill Lane Portchester Ceo Storm discharge at pumping station Company site name WICOR MILL LANE PORTCHESTER CEO - 108502 EA ID / permit SWS00945 · A01374 Outlet location SU6083004750 (OS grid reference) · View on Apple Maps WFD catchment PORTSMOUTH HARBOUR (GB580705140000) Shellfish water Portsmouth Harbour 2024 spills / hours 6 / 11 Long-term average 8.4 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement Env Act (SODRP) improvement ongoing, Bathing Water and/or Shellfish Water improvement ongoing Volume & pollution Estimate from 1.4 hours spilling →	Portsmouth Harbour	5	1.4	down 17%	100%
Herne Road Gillingham CSO Overflow on sewer network Company site name HERNE ROAD GILLINGHAM CSO - 107632 EA ID / permit SWS00420 · A01313 Outlet location TQ8146067890 (OS grid reference) · View on Apple Maps WFD catchment MEDWAY (GB530604002300) 2024 spills / hours 7 / 1.3 Long-term average 4.2 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.4 hours spilling →	River Medway	7	1.4	no change	100%
Cobham Street Gravesend CSO Overflow on sewer network Company site name COBHAM STREET GRAVESEND CSO - 108609 EA ID / permit SWS00187 · CASM.0029 Outlet location TQ6481074520 (OS grid reference) · View on Apple Maps WFD catchment THAMES MIDDLE (GB530603911402) 2024 spills / hours 5 / 8.1 Long-term average 4.8 spills a year (monitored since 2016) Monitor below 90% Sensor failure / issue · Scheduled Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.3 hours spilling →	Tidal River Thames	1	1.3	down 80%	67%
Eastern Gardens Wps Storm discharge at pumping station Company site name EASTERN GARDENS SANDOWN CEO - 108039 EA ID / permit SWS00277 · A01108 Outlet location SZ6035084320 (OS grid reference) · View on Apple Maps WFD catchment Isle of Wight East (GB650705530000) Bathing water Sandown; Shanklin; Yaverland 2024 spills / hours 5 / 4.0 Long-term average 3.0 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.3 hours spilling →	English Channel	2	1.3	down 60%	90%
Upper Shoreham Road Shoreham CSO Overflow on sewer network Company site name UPPER SHOREHAM ROAD SHOREHAM CSO - 108819 EA ID / permit SWS00896 · A01245 Outlet location TQ2119005130 (OS grid reference) · View on Apple Maps WFD catchment ADUR (GB540704116000) Bathing water Shoreham Beach; Southwick 2024 spills / hours 1 / 0.2 Long-term average 2.6 spills a year (monitored since 2016) Monitor below 90% Sensor failure / issue · Resolved - Jun Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.3 hours spilling →	River Adur	5	1.3	up 400%	86%
Empress Rd Denton Catch Chamb' CS0 Overflow on sewer network Company site name EMPRESS ROAD DENTON CATCH CHAMBERS 3 CSO - 116099 EA ID / permit SWS00289 · CASM.0006 Outlet location TQ6642074330 (OS grid reference) · View on Apple Maps WFD catchment THAMES MIDDLE (GB530603911402) 2024 spills / hours 1 / 0.5 Long-term average 3.2 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.2 hours spilling →	The Thames Estuary (Tidal)	2	1.2	up 100%	100%
The Parade PS Storm discharge at pumping station Company site name THE PARADE COWES CEO - 108548 EA ID / permit SWS00864 · A00637 Outlet location SZ4952096520 (OS grid reference) · View on Apple Maps WFD catchment Solent (GB650705150000) Bathing water Cowes; Gurnard Shellfish water Central Solent; Cowes and Medina; Lepe Middle Bank; Stanswood Bay 2024 spills / hours 1 / 2.0 Long-term average 1.0 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.2 hours spilling →	Cowes Harbour	1	1.2	no change	100%
Blackgang PS Storm discharge at pumping station Company site name BLACKGANG CHINE CEO - 108511 EA ID / permit SWS00070 · A00221 Outlet location SZ4866076820 (OS grid reference) · View on Apple Maps WFD catchment Dorset / Hampshire (GB620705550000) 2024 spills / hours 4 / 8.3 Long-term average 2.2 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.2 hours spilling →	Freshwater River	2	1.2	down 50%	100%
Village Road Alverstoke Ceo Storm discharge at pumping station Company site name VILLAGE ROAD ALVERSTOKE CEO - 108824 EA ID / permit SWS00902 · A01373 Outlet location SZ6033098700 (OS grid reference) · View on Apple Maps WFD catchment PORTSMOUTH HARBOUR (GB580705140000) Bathing water Southsea East; Stokes Bay Shellfish water Central Solent; Cowes and Medina; Portsmouth Harbour; Ryde; Spithead and Stokes Bay 2024 spills / hours 2 / 1.7 Long-term average 0.9 spills a year (monitored since 2016) Investigation Bathing Water and/or Shellfish Water investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 1.2 hours spilling →	Stoke Lake	2	1.2	no change	100%
Surf. Water Sewer Sittingbourne Storm discharge at pumping station Company site name CROWN QUAY LANE SITTINGBOURNE CSO - 108623 EA ID / permit SWS00841 · K02078 Outlet location TQ9111064060 (OS grid reference) · View on Apple Maps WFD catchment SWALE (GB530604011500) Shellfish water Swale Central 2024 spills / hours 5 / 5.7 Long-term average 4.0 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.1 hours spilling →	Unnamed Trib of Milton Creek	2	1.1	down 60%	100%
Lone Valley Waterlooville CSO Overflow on sewer network Company site name LONE VALLEY WATERLOOVILLE CSO - 108452 EA ID / permit SWS00516 · A01017 Outlet location SU6715007790 (OS grid reference) · View on Apple Maps WFD catchment Potwell Trib (GB107042016400) Shellfish water Langstone Harbour; Portsmouth Harbour 2024 spills / hours 0 / 0.0 Long-term average 0.1 spills a year (monitored since 2018) Monitor below 90% Sensor failure / issue · Resolved - May Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.1 hours spilling →	Tributary of River Wallington	1	1.1	up from 0	82%
Buckland East Tank Overflow on sewer network Company site name BROOKFIELD AVENUE DOVER CSO - 102720 EA ID / permit SWS00119 · A00716 Outlet location TR3003043020 (OS grid reference) · View on Apple Maps WFD catchment Dour from Kearsney to Dover (GB107040073310) 2024 spills / hours 2 / 0.6 Long-term average 5.1 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.1 hours spilling →	Freshwater River	2	1.1	no change	100%
Pennington Road Ceo Storm discharge at pumping station Company site name PENNINGTON ROAD SOUTHBOROUGH CEO - 108700 EA ID / permit SWS00654 · A00163 Outlet location TQ5855043030 (OS grid reference) · View on Apple Maps WFD catchment Somerhill Stream (GB106040018410) 2024 spills / hours 10 / 6.6 Long-term average 5.5 spills a year (monitored since 2019) Investigation Env Act (SODRP) investigation ongoing Improvement Env Act (SODRP) improvement ongoing Volume & pollution Estimate from 1.1 hours spilling →	Trib of River Medway	2	1.1	down 80%	100%
Town Farm Estate Pumping Station Storm discharge at pumping station Company site name TOWN FARM HAILSHAM CEO - 108367 EA ID / permit SWS00880 · S01758 Outlet location TQ6005009480 (OS grid reference) · View on Apple Maps WFD catchment Horse Eye Sewer (GB107041012420) 2024 spills / hours 9 / 28 Long-term average 6.5 spills a year (monitored since 2019) Investigation Env Act (SODRP) investigation ongoing Improvement Env Act (SODRP) improvement ongoing Volume & pollution Estimate from 1.0 hours spilling →	Freshwater River	1	1.0	down 89%	100%
London Road Burgess Hill CSO Overflow on sewer network Company site name LONDON ROAD BEXHILL CSO - 108171 EA ID / permit SWS00515 · A00744 Outlet location TQ3113020180 (OS grid reference) · View on Apple Maps WFD catchment R. Adur East (GB107041012220) Bathing water Bexhill 2024 spills / hours 0 / 0.0 Long-term average 3.0 spills a year (monitored since 2016) Investigation Env Act (SODRP) investigation ongoing, Bathing Water and/or Shellfish Water investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 1.0 hours spilling →	Controlled Sea	2	1.0	up from 0	97%
Mustards Road Pumping Station Storm discharge at pumping station Company site name MUSTARDS ROAD LEYSDOWN ON SEA CEO - 108113 EA ID / permit SWS00590 · A01215 Outlet location TR0174070700 (OS grid reference) · View on Apple Maps WFD catchment Whitstable Bay (GB640604290000) Bathing water Leysdown Shellfish water Sheppey; Swale Central; Swale East; Swalecliffe 2024 spills / hours 0 / 0.0 Long-term average 2.0 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 1.0 hours spilling →	Warden Bay Drain	2	1.0	up from 0	100%
Alver Road Gosport Ceo Storm discharge at pumping station Company site name ALVER ROAD GOSPORT CEO - 108838 EA ID / permit SWS00014 · A01391 Outlet location SZ6097099320 (OS grid reference) · View on Apple Maps WFD catchment PORTSMOUTH HARBOUR (GB580705140000) Bathing water Southsea East; Stokes Bay Shellfish water Central Solent; Cowes and Medina; Portsmouth Harbour; Ryde; Spithead and Stokes Bay 2024 spills / hours 4 / 9.9 Long-term average 1.1 spills a year (monitored since 2016) Investigation Bathing Water and/or Shellfish Water investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 1.0 hours spilling →	Workhouse Lake	1	1.0	down 75%	100%
Pier Road Gillingham No.1 CSO Overflow on sewer network Company site name SAUNDERS STREET GILLINGHAM CSO - 107454 EA ID / permit SWS00743 · A00139 Outlet location TQ7778069590 (OS grid reference) · View on Apple Maps WFD catchment MEDWAY (GB530604002300) 2024 spills / hours 0 / 0.0 Long-term average 4.3 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.9 hours spilling →	Gillingham Reach/ Medway Est	2	0.9	up from 0	100%
Oxford Road Shepway CSO Overflow on sewer network Company site name OXFORD ROAD SHEPWAY CSO - 108868 EA ID / permit SWS00635 · A01434 Outlet location TQ7793054080 (OS grid reference) · View on Apple Maps WFD catchment Len (GB106040018430) 2024 spills / hours 1 / 0.7 Long-term average 2.5 spills a year (monitored since 2019) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.9 hours spilling →	A Trib of the River Len	1	0.9	no change	99%
Warden Bay Pumping Station Storm discharge at pumping station Company site name WARDEN BAY CEO - 108114 EA ID / permit SWS00908 · A01154 Outlet location TR0238071300 (OS grid reference) · View on Apple Maps WFD catchment Whitstable Bay (GB640604290000) Bathing water Leysdown Shellfish water Sheppey; Swale East; Swalecliffe 2024 spills / hours 0 / 0.0 Long-term average 1.8 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.9 hours spilling →	A Trib of the North Sea	1	0.9	up from 0	100%
Aldwick Road/Victoria Road CSO Overflow on sewer network Company site name VICTORIA ROAD BOGNOR CSO - 103300 EA ID / permit SWS00012 · A00733 Outlet location SZ9284098610 (OS grid reference) · View on Apple Maps WFD catchment Sussex (GB640704540003) Bathing water Bognor Regis (Aldwick); Bognor Regis East; Felpham; Pagham 2024 spills / hours 4 / 7.6 Long-term average 2.6 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.9 hours spilling →	Controlled Sea	1	0.9	down 75%	100%
Ferndale Road Gillingham CSO Overflow on sewer network Company site name FERNDALE ROAD GILLINGHAM CSO - 108635 EA ID / permit SWS00306 · A01315 Outlet location TQ7890069120 (OS grid reference) · View on Apple Maps WFD catchment MEDWAY (GB530604002300) 2024 spills / hours 1 / 0.0 Long-term average 17.9 spills a year (monitored since 2016) Investigation UWWTR investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 0.9 hours spilling →	River Medway	3	0.9	up 200%	100%
Hensbrook Eastchurch PS Ceo Storm discharge at pumping station Company site name HENSBROOK EASTCHURCH CEO - 108111 EA ID / permit SWS00418 · A01336 Outlet location TQ9941072630 (OS grid reference) · View on Apple Maps WFD catchment THAMES LOWER (GB530603911401) Shellfish water Outer Thames; Sheppey; Swale Central; Swalecliffe 2024 spills / hours 0 / 0.0 Long-term average 3.2 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.9 hours spilling →	The Hens Brook	1	0.9	up from 0	100%
Lakeside Lee-on-Solent Ceo Storm discharge at pumping station Company site name LAKESIDE LEE ON THE SOLENT CEO - 108829 EA ID / permit SWS00488 · A01385 Outlet location SZ5671099670 (OS grid reference) · View on Apple Maps WFD catchment Solent (GB650705150000) Bathing water Hillhead; Lee-on-Solent; Stokes Bay Shellfish water Central Solent; Cowes and Medina; Ryde; Spithead and Stokes Bay 2024 spills / hours 0 / 0.0 Long-term average 0.8 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.9 hours spilling →	The Solent	1	0.9	up from 0	99%
Wincheap Canterbury CSO Overflow on sewer network Company site name WINCHEAP CANTERBURY CSO - 108759 EA ID / permit SWS00953 · A00917 Outlet location TR1399057420 (OS grid reference) · View on Apple Maps WFD catchment Great Stour between A2 and West Stourmouth (GB107040019743) 2024 spills / hours 17 / 46 Long-term average 12.9 spills a year (monitored since 2018) Investigation UWWTR investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 0.9 hours spilling →	The Great Stour	3	0.9	down 82%	96%
Seaview Wps Storm discharge at pumping station Company site name ESPLANADE SEAVIEW CEO - 108555 EA ID / permit SWS00758 · A00766 Outlet location SZ6296091670 (OS grid reference) · View on Apple Maps WFD catchment Solent (GB650705150000) Bathing water Ryde; Seagrove; St Helens Shellfish water Ryde; Spithead and Stokes Bay 2024 spills / hours 4 / 2.7 Long-term average 2.7 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.8 hours spilling →	The Solent	2	0.8	down 50%	100%
Mount Noddy Cem. East Grinstead CSO Overflow on sewer network Company site name MOUNT NODDY CEMETERY EAST GRINSTEAD CSO - 108260 EA ID / permit SWS00588 · A01470 Outlet location TQ3982038790 (OS grid reference) · View on Apple Maps WFD catchment Shovelstrode Stream (GB106040018080) 2024 spills / hours 1 / 1.0 Long-term average 2.0 spills a year (monitored since 2019) Monitor below 90% Sensor failure / issue · Resolved - Oct Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.8 hours spilling →	Unamed Trib of Medway via Pond	1	0.8	no change	84%
Reading Street W.W.T.W Inlet overflow at sewage works Sewage works Reading Street W W T W Company site name READING STREET CSO - 116042 EA ID / permit SWS00697 · A01175 Outlet location TQ9224030350 (OS grid reference) · View on Apple Maps WFD catchment Reading Sewer, Small Hythe to Reading Street (GB107040013520) 2024 spills / hours 0 / 0.0 Long-term average 2.9 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.8 hours spilling →	The Reading Sewer	1	0.8	up from 0	100%
Foxborough Close Settled Storm Tank Storm discharge at pumping station Company site name FOXBOROUGH CLOSE WOODNESBOROUGH SSO - 115970 EA ID / permit SWS00328 · A01465 Outlet location TR3062056510 (OS grid reference) · View on Apple Maps WFD catchment North and South Streams in the Lydden Valley (GB107040019550) 2024 spills / hours 0 / 0.0 Long-term average 1.3 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.7 hours spilling →	Unnamed Ditch Trib River Stour	1	0.7	up from 0	100%
Gillingham Road Gillingham CSO Overflow on sewer network Company site name GILLINGHAM ROAD GILLINGHAM CSO - 100080 EA ID / permit SWS00347 · Permit applied for Outlet location SZ8665593439 (OS grid reference) · View on Apple Maps WFD catchment Sussex (GB640704540003) 2024 spills / hours 0 / 0.0 Long-term average 4.3 spills a year (monitored since 2023) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.7 hours spilling →	The English Channel	6	0.7	up from 0	100%
Marsh Road, Halling Combined EO Storm discharge at pumping station Company site name MARSH ROAD HALLING CEO - 111646 EA ID / permit SWS00556 · W00023 Outlet location TQ7099064420 (OS grid reference) · View on Apple Maps WFD catchment MEDWAY (GB530604002300) 2024 spills / hours 0 / 0.0 Long-term average 0.3 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.7 hours spilling →	The Tidal River Medway	1	0.7	up from 0	100%
Southcliff Road/Liverpool Street Overflow on sewer network Company site name LIVERPOOL STREET SOUTHAMPTON CSO - 108482 EA ID / permit SWS00798 · A00373 Outlet location SU4307013070 (OS grid reference) · View on Apple Maps WFD catchment SOUTHAMPTON WATER (GB520704202800) Shellfish water Southampton Water 2024 spills / hours 3 / 1.1 Long-term average 1.9 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.7 hours spilling →	Itchen Estuary	3	0.7	no change	100%
Wykeham Close Steyning CSO Overflow on sewer network Company site name WYKEHAM CLOSE STEYNING CSO - 108251 EA ID / permit SWS00975 · A00898 Outlet location TQ1818011590 (OS grid reference) · View on Apple Maps WFD catchment Black Sewer (GB107041012040) 2024 spills / hours – / – Long-term average 14.0 spills a year (monitored since 2019) Monitor below 90% Sensor failure / issue · Scheduled Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.7 hours spilling →	The River Adur	2	0.7		25%
Park Road Burgess Hill CSO Overflow on sewer network Company site name PARK ROAD BURGESS HILL CSO - 109220 EA ID / permit SWS00641 · A01255 Outlet location TQ3046018730 (OS grid reference) · View on Apple Maps WFD catchment Herrings Stream (GB107041012150) 2024 spills / hours 1 / 1.3 Long-term average 3.2 spills a year (monitored since 2019) Monitor below 90% Sensor failure / issue · Resolved - May Investigation Env Act (SODRP) investigation ongoing Improvement Env Act (SODRP) improvement ongoing Volume & pollution Estimate from 0.6 hours spilling →	Pookbourne Stream	2	0.6	up 100%	62%
Lion Point Transfer PS Storm discharge at pumping station Company site name LION POINT VENTNOR CEO - 108546 EA ID / permit SWS00509 · A00702 Outlet location SZ5628077190 (OS grid reference) · View on Apple Maps WFD catchment Isle of Wight East (GB650705530000) Bathing water Ventnor 2024 spills / hours 12 / 174 Long-term average 4.8 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.6 hours spilling →	English Channel	1	0.6	down 92%	100%
The Green Southwick CSO Overflow on sewer network Company site name THE GREEN SOUTHWICK CSO - 108356 EA ID / permit SWS00861 · A01005 Outlet location TQ2382004930 (OS grid reference) · View on Apple Maps WFD catchment ADUR (GB540704116000) Bathing water Shoreham Beach; Southwick 2024 spills / hours 81 / 1,309 Long-term average 13.3 spills a year (monitored since 2016) Investigation UWWTR investigation ongoing Improvement No improvement action in reporting period Volume & pollution Estimate from 0.6 hours spilling →	The Adur Estuary	1	0.6	down 99%	90%
Framfield Road Sewage Pumping Storm discharge at pumping station Company site name FRAMFIELD ROAD UCKFIELD CEO - 108227 EA ID / permit SWS00331 · A00664 Outlet location TQ4791020820 (OS grid reference) · View on Apple Maps WFD catchment Framfield Stream (GB107041012650) 2024 spills / hours 2 / 0.7 Long-term average 5.6 spills a year (monitored since 2016) Investigation No investigation activity in reporting period Improvement No improvement action in reporting period Volume & pollution Estimate from 0.6 hours spilling →	Freshwater River	1	0.6	down 50%	100%

Sewage treatment works

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

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