Overflow history upstream of River Thames, Hurley
The spot's forecast · For event organisers
This page lists the monitored storm overflows upstream of this spot and how often each spilled in each year. It is not a water test, and it does not say whether the water is fit to swim in. It does not include farm runoff, misconnected drains, treated sewage effluent, wildlife or overflows without a monitor. A year's count depends on how long the monitor worked, shown as monitor uptime.
Each year, all overflows upstream
| Year | Overflows with a return | Spills | Spill hours | Spill hours, weighted by reach |
|---|---|---|---|---|
| 2021 | 41 | 1,510 | 20,256 | 280 |
| 2022 | 41 | 784 | 9,538 | 30 |
| 2023 | 43 | 1,765 | 25,248 | 402 |
| 2024 | 44 | 2,409 | 32,704 | 321 |
| 2025 | 44 | 857 | 12,111 | 67 |
Reach is the share of a spill's bacteria SwimSignal's model expects to arrive here, after die-off on the way and dilution by the river. Weighting by it counts an hour of spilling just upstream for far more than one 40 km away. Spills are counted by the Environment Agency's 12/24 method: any discharge in the first 12 hours counts as one spill, then one more for each 24 hours with any discharge. How reach is worked out.
The overflows, by reach
All 44, the one whose spills matter most here first. Hours away is how long sewage takes to arrive at the model's river speed.
| Overflow and id | Company | km upstream | Hours away | Reach | Spills 2023 | Spills 2024 | Spills 2025 | Spill hours 2025 | Monitor uptime 2025 |
|---|---|---|---|---|---|---|---|---|---|
| Hambleden sewage works overflow Hambleden STW · TWL00209 | Thames Water | 5.0 | 3 | 80% | 20 | 8 | 0 | 0 | 96% |
| Friday Street (Henley) pumping station overflow Friday Street (Henley) SPS · TWL00191 | Thames Water | 9.4 | 5 | 65% | 14 | 17 | 4 | 10 | 98% |
| Wargrave sewage works overflow Wargrave STW · TWL00428 | Thames Water | 16.7 | 9 | 23% | 28 | 46 | 12 | 121 | 100% |
| Caversham (Reading) pumping station overflow Caversham (Reading) SPS · TWL00345 | Thames Water | 23.7 | 13 | 7% | 0 | 0 | 0 | 0 | 91% |
| Reading sewage works overflow Reading STW · TWL00343 | Thames Water | 27.6 | 15 | 2% | 24 | 47 | 14 | 168 | 99% |
| New Mill sewage works overflow New Mill STW · TWL00176 | Thames Water | 38.4 | 21 | 2% | 36 | 68 | 27 | 325 | 99% |
| Goring sewage works overflow Goring STW · TWL00199 | Thames Water | 43.9 | 24 | 2% | 0 | 0 | 0 | 0 | 100% |
| Hartley Wintney sewage works overflow Hartley Wintney STW · TWL00216 | Thames Water | 44.4 | 25 | 1% | 46 | 39 | 21 | 300 | 100% |
| Mortimer sewage works overflow Mortimer STW · TWL00306 | Thames Water | 37.3 | 21 | 1% | 150 | 63 | 40 | 689 | 100% |
| Pangbourne sewage works overflow Pangbourne STW · TWL00324 | Thames Water | 34.6 | 19 | 0% | 5 | 70 | 14 | 271 | 100% |
| Sherfield-on-Loddon sewage works overflow Sherfield-on-Loddon STW · TWL00366 | Thames Water | 44.4 | 25 | 0% | 67 | 60 | 26 | 405 | 99% |
| Arborfield sewage works overflow Arborfield STW · TWL00014 | Thames Water | 30.6 | 17 | <1% | 52 | 53 | 28 | 251 | 100% |
| Henley sewage works overflow Henley STW · TWL00222 | Thames Water | 9.0 | 5 | <1% | 1 | 86 | 0 | 0 | 100% |
| Fleet sewage works overflow Fleet STW · TWL00186 | Thames Water | 49.7 | 28 | <1% | 86 | 103 | 39 | 525 | 99% |
| Crooked Billet (Hook) & Storm pumping station overflow Crooked Billet (Hook) SPS & Storm SPS · TWL00121 | Thames Water | 48.1 | 27 | <1% | 15 | 19 | 7 | 13 | 100% |
| Cholsey sewage works overflow Cholsey STW · TWL00097 | Thames Water | 50.8 | 28 | <1% | 2 | 45 | 4 | 44 | 99% |
| Newbury sewage works overflow Newbury STW · TWL00309 | Thames Water | 55.7 | 31 | <1% | 61 | 94 | 28 | 381 | 100% |
| Ash Ridge (Wokingham) sewage works overflow Ash Ridge (Wokingham) STW · TWL00459 | Thames Water | 27.6 | 15 | <1% | 20 | 74 | 11 | 136 | 100% |
| Easthampstead Park sewage works overflow Easthampstead Park STW · TWL00169 | Thames Water | 33.7 | 19 | <1% | 30 | 42 | 16 | 160 | 98% |
| Waterloo crescent outfall, wokingham TWL00756 | Thames Water | 31.6 | 18 | <1% | – | 29 | 7 | 17 | 100% |
| Water End (Newnham) pumping station overflow Water End (Newnham) SPS · TWL00431 | Thames Water | 52.1 | 29 | <1% | 1 | 2 | 0 | 0 | 100% |
| Burghfield sewage works overflow Burghfield STW · TWL00064 | Thames Water | 34.2 | 19 | <1% | 132 | 96 | 34 | 655 | 100% |
| South Moreton sewage works overflow South Moreton STW · TWL00378 | Thames Water | 56.4 | 31 | <1% | 162 | 261 | 137 | 2,721 | 99% |
| Silchester sewage works overflow Silchester STW · TWL00370 | Thames Water | 45.2 | 25 | <1% | 112 | 97 | 42 | 760 | 100% |
| Kingsclere sewage works overflow Kingsclere STW · TWL00256 | Thames Water | 56.9 | 32 | <1% | 134 | 119 | 49 | 852 | 100% |
| Aldermaston sewage works overflow Aldermaston STW · TWL00006 | Thames Water | 44.2 | 25 | <1% | 39 | 48 | 31 | 248 | 100% |
| Benson sewage works overflow Benson STW · TWL00034 | Thames Water | 53.1 | 30 | <1% | 12 | 101 | 18 | 361 | 97% |
| Chapel Row sewage works overflow Chapel Row STW · TWL00081 | Thames Water | 47.1 | 26 | <1% | 85 | 112 | 21 | 253 | 95% |
| Beenham sewage works overflow Beenham STW · TWL00031 | Thames Water | 45.4 | 25 | <1% | 62 | 54 | 14 | 132 | 100% |
| Ash Vale sewage works overflow Ash Vale STW · TWL00017 | Thames Water | 58.3 | 32 | <1% | 15 | 23 | 9 | 103 | 100% |
| Dorchester sewage works overflow Dorchester STW · TWL00157 | Thames Water | 59.4 | 33 | <1% | 4 | 63 | 15 | 121 | 100% |
| Hampstead Norreys sewage works overflow Hampstead Norreys STW · TWL00211 | Thames Water | 55.0 | 31 | <1% | 83 | 55 | 33 | 628 | 100% |
| Sandhurst sewage works overflow Sandhurst STW · TWL00359 | Thames Water | 48.3 | 27 | <1% | 18 | 37 | 10 | 114 | 100% |
| St Stephens Hall (Little London) pumping station overflow St Stephens Hall (Little London) SPS · TWL00319 | Thames Water | 52.6 | 29 | <1% | 60 | 72 | 21 | 18 | 100% |
| Briff Lane (Bucklebury) sewage works overflow Briff Lane (Bucklebury) STW · TWL00061 | Thames Water | 49.6 | 28 | <1% | 85 | 73 | 23 | 221 | 100% |
| Swains Road (Tadley) pumping station overflow Swains Road (Tadley) SPS · TWL00401 | Thames Water | 48.1 | 27 | <1% | 2 | 2 | 1 | 5 | 97% |
| Camberley sewage works overflow Camberley STW · TWL00070 | Thames Water | 51.6 | 29 | <1% | 26 | 25 | 7 | 69 | 100% |
| Wedmans Lane (Rotherwick) pumping station overflow Wedmans Lane (Rotherwick) SPS · TWL00354 | Thames Water | 45.4 | 25 | <1% | 6 | 11 | 8 | 74 | 100% |
| Basingstoke sewage works overflow Basingstoke STW · TWL00028 | Thames Water | 51.6 | 29 | <1% | 6 | 82 | 40 | 397 | 100% |
| Midgham sewage works overflow Midgham STW · TWL00301 | Thames Water | 47.9 | 27 | <1% | 3 | 3 | 1 | 6 | 99% |
| Elvetham Road (Fleet) pumping station overflow Elvetham Road (Fleet) SPS · TWL00171 | Thames Water | 50.6 | 28 | <1% | 3 | 9 | 7 | 10 | 78% |
| Knightsbridge Road, Camberley TWL00627 | Thames Water | 51.7 | 29 | <1% | 2 | 2 | 0 | 0 | 66% |
| Avondale Road (Fleet) pumping station overflow Avondale Road (Fleet) SPS · TWL00021 | Thames Water | 52.9 | 29 | <1% | 0 | 0 | 0 | 0 | 98% |
| West Heath (Charter Alley) pumping station overflow West Heath (Charter Alley) SPS · TWL00437 | Thames Water | 54.6 | 30 | 0% | 56 | 99 | 38 | 547 | 88% |
A dash: no annual return for that overflow in that year.
Sources and credits
Storm overflow annual returns: © Environment Agency copyright and/or database right 2025, Open Government Licence v3.0. Overflow positions: the water companies via the National Storm Overflow Hub, CC BY 4.0. River network: contains OS data © Crown copyright and database right 2026 (OS Open Rivers). Traced and weighted by SwimSignal (swimsignal.co.uk), whose method is at swimsignal.co.uk/methods.html. All credits and licences.