Overflow history upstream of Wharfe at Wilderness Carpark
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 | 49 | 2,065 | 13,308 | 2,028 |
| 2022 | 50 | 1,640 | 9,866 | 1,479 |
| 2023 | 50 | 2,493 | 21,931 | 4,092 |
| 2024 | 51 | 2,142 | 15,831 | 2,507 |
| 2025 | 51 | 1,642 | 11,045 | 1,564 |
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 52, 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 |
|---|---|---|---|---|---|---|---|---|---|
| Scott Lane storm overflow Scott Lane/CSO · YWS01175 | Yorkshire Water | 0.2 | under 1 | 98% | 15 | 14 | 20 | 23 | 98% |
| Wattle Syke storm overflow Wattle Syke/CSO · YWS00218 | Yorkshire Water | 2.8 | 2 | 88% | 2 | 0 | 1 | 10 | 82% |
| Langwith Valley storm overflow Langwith Valley/CSO · YWS00204 | Yorkshire Water | 5.4 | 3 | 73% | 2 | 9 | 3 | 1 | 100% |
| Kearby sewage works overflow Kearby/STW · YWS00213 | Yorkshire Water | 10.9 | 6 | 57% | 54 | 38 | 35 | 304 | 100% |
| Weeton sewage works overflow Weeton/STW · YWS00214 | Yorkshire Water | 14.9 | 8 | 44% | 194 | 164 | 92 | 836 | 100% |
| Warren Lane Otley storm overflow Warren Lane Otley/CSO · YWS00202 | Yorkshire Water | 20.4 | 11 | 34% | 10 | 10 | 8 | 28 | 99% |
| Pool sewage works storm tank overflow Pool/STW/3Xdwf Overflow · YWS00199 | Yorkshire Water | 20.5 | 11 | 34% | 152 | 100 | 78 | 963 | 100% |
| Pool sewage works overflow Pool/STW/6Xdwf Overflow · YWS00200 | Yorkshire Water | 20.5 | 11 | 34% | 31 | 54 | 14 | 117 | 100% |
| Arthington Lane storm overflow Arthington Lane/CSO · YWS00215 | Yorkshire Water | 23.1 | 13 | 29% | 26 | 20 | 20 | 42 | 100% |
| Otley sewage works overflow Otley/STW · YWS00192 | Yorkshire Water | 27.9 | 16 | 17% | 113 | 85 | 42 | 367 | 100% |
| Otley sewage works overflow Otley/STW · YWS00193 | Yorkshire Water | 28.0 | 16 | 17% | 0 | 0 | 0 | 0 | 100% |
| Otley Bridge Street storm overflow Otley Bridge Street/CSO · YWS01289 | Yorkshire Water | 29.0 | 16 | 16% | 39 | 15 | 11 | 23 | 68% |
| Ilkley Road storm overflow Ilkley Road/CSO · YWS01270 | Yorkshire Water | 29.7 | 16 | 15% | 64 | 46 | 28 | 52 | 100% |
| West Busk Lane storm overflow 2 West Busk Lane/NO 2 CSO · YWS00206 | Yorkshire Water | 30.3 | 17 | 15% | 32 | 21 | 19 | 20 | 100% |
| Burley in Wharfedale sewage works overflow Burley IN Wharfedale/STW · YWS00893 | Yorkshire Water | 31.3 | 17 | 13% | 132 | 126 | 80 | 1,144 | 100% |
| Burley Lodge storm overflow Burley Lodge/CSO · YWS01338 | Yorkshire Water | 32.5 | 18 | 12% | 6 | 6 | 12 | 38 | 100% |
| Ben Rhydding sewage works overflow BEN Rhydding/STW · YWS00173 | Yorkshire Water | 36.5 | 20 | 9% | 140 | 158 | 127 | 1,758 | 100% |
| Wyvil Crescent storm overflow Wyvil Crescent/CSO · YWS00171 | Yorkshire Water | 38.2 | 21 | 8% | 107 | 87 | 80 | 595 | 100% |
| Wheatley Lane storm overflow 2 Wheatley Lane/2 CSO · YWS01032 | Yorkshire Water | 38.2 | 21 | 8% | 78 | 50 | 49 | 255 | 100% |
| Wyvill Road storm overflow Wyvill Road/CSO · YWS01033 | Yorkshire Water | 38.4 | 21 | 8% | 0 | 0 | 0 | 0 | 100% |
| YWS02298 YWS02298 | Yorkshire Water | 38.6 | 21 | 7% | – | – | – | – | – |
| Ilkley sewage works overflow Ilkley/STW/6Xdwf Overflow · YWS00175 | Yorkshire Water | 39.5 | 22 | 7% | 82 | 74 | 71 | 298 | 100% |
| Ilkley sewage works storm tank overflow Ilkley/STW/3Xdwf Overflow · YWS00174 | Yorkshire Water | 39.5 | 22 | 7% | 67 | 63 | 65 | 727 | 94% |
| Ilkley Middleton storm overflow Ilkley Middleton/CSO · YWS00176 | Yorkshire Water | 39.7 | 22 | 7% | 49 | 38 | 24 | 214 | 100% |
| Rivadale View storm overflow Rivadale View/CSO · YWS00674 | Yorkshire Water | 40.2 | 22 | 6% | 65 | 40 | 20 | 48 | 100% |
| Addingham sewage works overflow Addingham/NO 1 SPS/Preliminary Treatment-STW/6Xdwf Overflow · YWS00145 | Yorkshire Water | 43.8 | 24 | 5% | 100 | 23 | 28 | 61 | 100% |
| Addingham sewage works storm tank overflow Addingham/NO 1 SPS/Preliminary Treatment-STW/3Xdwf Overflow · YWS00144 | Yorkshire Water | 43.8 | 24 | 5% | 94 | 66 | 41 | 371 | 100% |
| Collingham Leeds Road storm overflow Collingham Leeds Road/CSO · YWS01160 | Yorkshire Water | 5.5 | 3 | 5% | 17 | 65 | 67 | 430 | 96% |
| Meadow Close storm overflow Meadow Close/CSO · YWS00212 | Yorkshire Water | 6.9 | 4 | 4% | 73 | 30 | 47 | 192 | 100% |
| Bardsey the Drive storm overflow Bardsey THE Drive/CSO · YWS00210 | Yorkshire Water | 7.7 | 4 | 3% | 14 | 15 | 7 | 10 | 87% |
| Bolton Bridge storm overflow Bolton Bridge/CSO · YWS00828 | Yorkshire Water | 48.9 | 27 | 2% | 20 | 10 | 5 | 24 | 98% |
| Hetchell View storm overflow 2 Hetchell View/NO 2 CSO · YWS00211 | Yorkshire Water | 9.0 | 5 | 2% | 112 | 65 | 23 | 292 | 100% |
| Scarcroft storm overflow Scarcroft/CSO · YWS00728 | Yorkshire Water | 11.3 | 6 | 2% | 19 | 30 | 25 | 51 | 100% |
| Bridge House Farm storm overflow Bridge House Farm/CSO · YWS00205 | Yorkshire Water | 16.0 | 9 | 2% | 67 | 50 | 36 | 231 | 100% |
| Bardsey storm overflow Bardsey/CSO · YWS00021 | Yorkshire Water | 9.2 | 5 | 1% | 3 | 7 | 3 | 8 | 100% |
| Shadwell storm overflow Shadwell/CSO · YWS00203 | Yorkshire Water | 14.4 | 8 | 1% | 63 | 64 | 47 | 124 | 100% |
| Beamsley sewage works overflow Beamsley/STW · YWS01340 | Yorkshire Water | 48.3 | 27 | 1% | 77 | 104 | 120 | 118 | 100% |
| Crook Farm storm overflow Crook Farm/CSO · YWS01304 | Yorkshire Water | 22.8 | 13 | 0% | 33 | 56 | 44 | 141 | 100% |
| Netherfield Road storm overflow Netherfield Road/CSO · YWS01121 | Yorkshire Water | 34.3 | 19 | 0% | 3 | 17 | 10 | 22 | 100% |
| Billams Hill storm overflow Billams Hill/CSO · YWS01280 | Yorkshire Water | 29.0 | 16 | <1% | 76 | 64 | 49 | 133 | 100% |
| Askwith storm overflow Askwith/CSO · YWS00178 | Yorkshire Water | 35.0 | 19 | <1% | 53 | 44 | 29 | 98 | 100% |
| Leeds Road Ilkley storm overflow 2 Leeds Road Ilkley/2 CSO · YWS00172 | Yorkshire Water | 39.0 | 22 | <1% | 0 | 0 | 0 | 0 | 100% |
| Westbourne Drive storm overflow 2 Westbourne Drive/NO 2 CSO · YWS00184 | Yorkshire Water | 32.7 | 18 | <1% | 23 | 17 | 9 | 12 | 100% |
| Menston Cemetery storm overflow Menston Cemetery/CSO · YWS00180 | Yorkshire Water | 32.7 | 18 | <1% | 63 | 55 | 41 | 98 | 97% |
| Station Road storm overflow 2 Station Road/NO 2 CSO · YWS00182 | Yorkshire Water | 32.7 | 18 | <1% | – | 0 | 0 | 0 | 83% |
| Westbourne Drive storm overflow 1 Westbourne Drive/NO 1 CSO · YWS00183 | Yorkshire Water | 32.7 | 18 | <1% | 45 | 28 | 15 | 14 | 100% |
| Station Road storm overflow 1 Station Road/NO 1 CSO · YWS00181 | Yorkshire Water | 32.7 | 18 | <1% | 13 | 10 | 4 | 5 | 97% |
| Alwoodley storm overflow Alwoodley/CSO · YWS00197 | Yorkshire Water | 24.7 | 14 | <1% | 35 | 37 | 24 | 70 | 100% |
| Draughton sewage works overflow Draughton/STW/6Xdwf Overflow · YWS00189 | Yorkshire Water | 52.1 | 29 | <1% | 14 | 47 | 56 | 629 | 100% |
| Bridge Lane storm overflow Bridge Lane/CSO · YWS00179 | Yorkshire Water | 40.9 | 23 | <1% | 3 | 0 | 0 | 0 | 97% |
| Draughton Priors Lane storm overflow Draughton Priors Lane/CSO · YWS00188 | Yorkshire Water | 52.1 | 29 | <1% | 4 | 15 | 7 | 28 | 67% |
| Low Mill Lane 179 storm overflow LOW Mill Lane 179/CSO · YWS00191 | Yorkshire Water | 44.7 | 25 | <1% | 9 | 5 | 6 | 17 | 96% |
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.