Official records compared
Permitted overflows not found on the hub
The Environment Agency's public register lists every permit held by a water company to discharge storm sewage in England. The National Storm Overflow Hub lists the overflows the companies report on. We compare the two.
Active storm sewage permits
10,935
No hub overflow within 500 m
1,297
Share
11.9%
What this does and does not show
The data shows a permitted storm sewage discharge point on the EA register with no overflow published on the hub within 500 m. It does not show that an overflow is unmonitored or that anything is wrong. Common reasons for a gap:
- the permit's grid reference is approximate or marks the works, not the outfall;
- one permit covers an overflow the hub lists under a different location;
- the overflow is not published on the hub.
35 active permits have no usable grid reference on the register and are left out. Each row links to the EA register so it can be checked. England only: Welsh permits are held by Natural Resources Wales. Company names are as recorded on the register. Register last read 2026-09-20.
By company
| Permit holder | Permits | Within 100 m | 100 to 500 m | Over 500 m |
|---|---|---|---|---|
| Severn Trent Water Limited | 1,989 | 977 | 626 | 386 |
| Wessex Water Services Limited | 874 | 442 | 262 | 170 |
| Northumbrian Water Limited | 1,330 | 817 | 373 | 140 |
| United Utilities Water Limited | 2,083 | 1,834 | 119 | 130 |
| Yorkshire Water Services Limited | 1,697 | 1,367 | 215 | 115 |
| Southern Water Services Limited | 708 | 470 | 124 | 114 |
| Anglian Water Services Limited | 995 | 683 | 208 | 104 |
| South West Water Limited | 904 | 544 | 265 | 95 |
| Thames Water Utilities Limited | 254 | 170 | 56 | 28 |
| Dŵr Cymru Cyfyngedig | 95 | 61 | 22 | 12 |
| Ancala Water Services (Estates) Limited | 3 | 0 | 1 | 2 |
| Yorkshire Water Services Limited|Northumbrian Water Limited | 1 | 0 | 0 | 1 |
| Severn Trent Water Limited|Environmental Permits Severn Trent Water | 1 | 1 | 0 | 0 |
| Severn Trent Water Limited|Yorkshire Water Services Limited | 1 | 0 | 1 | 0 |
Thames Water Utilities Limited: 28 permits with no hub overflow within 500 m
| Site (register name) | Area | Grid ref | Nearest hub overflow | Permit |
|---|---|---|---|---|
| BENINGTON SEWAGE PUMPING STATION | East Hertfordshire | TL2961022830 | 7.1 km | TH/CLCP.0116/001 |
| BIRCH GREEN SEWAGE PUMPING STATION | East Hertfordshire | TL2920010980 | 2.1 km | TH/CLCR.0181/001 |
| HANGER LANE CSO | Ealing | TQ1865080860 | 2.0 km | TH/EPRAB3796VT/001 |
| Canterbury Road, Thornton Heath | Croydon | TQ3130066900 | 1.9 km | TH/TEMP.2514/002 |
| WESTON PARK CSO | Haringey | TQ3021088400 | 1.8 km | TH/EPRCB3293RE/001 |
| CSO AT LONGSTONE AVE | Brent | TQ2198083830 | 1.8 km | TH/TEMP.2749/003 |
| ACTON PS SR CSO | Ealing | TQ2132079550 | 1.7 km | TH/TEMP.0312/003 |
| CSO AT ALLENDALE ROAD | Ealing | TQ1648084910 | 1.5 km | TH/TEMP.2367/003 |
| CSO AT EASTCOTE AVENUE | Ealing | TQ1648084980 | 1.5 km | TH/TEMP.2580/003 |
| CSO AT HIGH ROAD | Redbridge | TQ4011090530 | 1.5 km | TH/TEMP.2681/003 |
| WORPLE ROAD CSO | Merton | TQ2380069800 | 1.5 km | TH/TEMP.3044/003 |
| CSO AT DISTRICT ROAD | Brent | TQ1663085090 | 1.4 km | TH/TEMP.2551/003 |
| CSO AT SUDBURY HEIGHTS AVE | Ealing | TQ1665084970 | 1.4 km | TH/TEMP.2944/003 |
| BOURTON ON THE WATER CSO | Cotswold | SP1815020031 | 1.1 km | TH/CTCR.2036/002 |
| CSO AT MULBERRY COURT, | Waltham Forest | TQ3892085790 | 1.0 km | TH/TEMP.2801/003 |
| NUTTER LANE / PRESTON DRIVE CSO | Redbridge | TQ4050088500 | 1.0 km | TH/CEVR.0138/002 |
| CS0 AT LINDSAY DRIVE | Brent | TQ1938088360 | 0.9 km | TH/TEMP.2739/003 |
| CSO AT LEOPOLD ROAD | Brent | TQ2149084180 | 0.8 km | TH/TEMP.2737/003 |
| N Woolwich P.S., Albert Road | Newham | TQ4373079800 | 0.8 km | TH/TEMP.2366/002 |
| Beddington | Sutton | TQ2830066800 | 0.8 km | TH/TEMP.2381/002 |
| GREENWICH PS CSO | Greenwich | TQ3889078150 | 0.7 km | TH/CSAB.0537/002 |
| Farnham | Waverley | SU8530047400 | 0.7 km | TH/TEMP.2589/002 |
| FOLKESTONE ROAD | Newham | TQ4347883131 | 0.7 km | TH/CSBC.0127/001 |
| SWS | Guildford | SU9860050300 | 0.7 km | TH/CTCR.2000/001 |
| CSO AT AMYAND PARK ROAD, | Richmond upon Thames | TQ1650073900 | 0.6 km | TH/TEMP.2369/003 |
| CSO AT OAKENTROUGH | Newham | TQ4354083230 | 0.6 km | TH/CANM.0029/002 |
| Broadwell | Cotswold | SP2220027500 | 0.6 km | TH/TEMP.2418/002 |
| CSO AT GAP ROAD (CEMETERY) | Merton | TQ2540071600 | 0.5 km | TH/TEMP.2630/003 |
Sources: Environment Agency public register, Discharges to Water and Groundwater (Environment Agency Conditional Licence); National Storm Overflow Hub. The register is read weekly and every download is archived with a SHA-256 fingerprint (see how we keep the record).