| 293 Preston Old Road CSO (052m0) | River Blakewater | Not Discharging | 24:00 Jan 01 1970 | 23:52 Jan 18 |
| 293 Preston Old Road CSO (052m0) | River Darwen | Not Discharging | 08:32 Jan 04 | 23:52 Jan 18 |
| Accrington Road CSO | Culverted section of Knuzden Brook | Not Discharging | 24:29 Jan 06 | 23:52 Jan 18 |
| Addison Close CSO | River Blakewater a tributary of the River Darwen | Not Discharging | 22:00 Jan 05 | 23:52 Jan 18 |
| Apple Street CSO | River Blakewater | Not Discharging | 19:10 Dec 31 2024 | 23:52 Jan 18 |
| Appleby Sreett CSO | Culverted tributary of the River Blakewater, a tributary of the River Darwen | Not Discharging | 08:30 Jan 06 | 23:52 Jan 18 |
| Aqueduct Road CSO | River Darwen | Not Discharging | 16:44 Jan 14 | 23:52 Jan 18 |
| Back Queens Park Rd | Culverted Tributary of River Blakewater | Not Discharging | 07:30 Dec 20 2024 | 23:52 Jan 18 |
| Beechwood Road CSO | River Blakewater | Not Discharging | 19:10 Dec 31 2024 | 23:52 Jan 18 |
| Bolton Road Combined Sewer Overflow | River Darwen | Not Discharging | 21:40 Jan 05 | 23:52 Jan 18 |
| Brownhill Drive CSO | Culverted Tributary of River Blakewater | Not Discharging | 19:32 Dec 31 2024 | 23:52 Jan 18 |
| Cherry Tree Works Site | River Darwen | Not Discharging | 23:00 Jan 18 | 23:52 Jan 18 |
| Cumberland Street CSO | Queens Park Culvert (Tributary of River Blakewater) | Not Discharging | 21:26 Jan 05 | 23:52 Jan 18 |
| Daisy Lane CSO | River Blakewater | Not Discharging | 24:00 Jan 01 1970 | 23:52 Jan 18 |
| Dickens Street CSO | Queens Park Culvert (tributary of River Blakewater) | Not Discharging | 11:30 Jan 06 | 23:52 Jan 18 |
| Dukes Brow CSO | River Blakewater | Not Discharging | 06:36 Jan 01 | 23:52 Jan 18 |
| Fielden Street CSO | River Blakewater, a tributary of the River Darwen | Not Discharging | 24:00 Jan 01 1970 | 23:52 Jan 18 |
| Gate Street CSO | Culverted tributary of River Blakewater | Not Discharging | 06:34 Jan 01 | 23:52 Jan 18 |
| Gorse St Combined Sewer Overflow | River Darwen | Not Discharging | 21:04 Jan 05 | 23:52 Jan 18 |
| Great Bolton Street CSO | River Blakewater | Not Discharging | 05:18 Aug 13 2024 | 23:52 Jan 18 |
| Grimshaw Park CSO | Culverted section of an unnamed trib. of River Blakewater | Not Discharging | 24:00 Jan 01 1970 | 23:52 Jan 18 |
| Infirmary Street CSO 05050 | Leeds Liverpool Canal | Not Discharging | 02:24 Jan 01 | 23:52 Jan 18 |
| Lark Hill/Brookhouse Lane CSO | Culverted tributary of River Blakewater | Not Discharging | 13:44 Oct 11 2024 | 23:52 Jan 18 |
| Lower Audley CSO | Culverted tributary of River Blakewater | Not Discharging | 21:26 Jan 06 | 23:52 Jan 18 |
| Manor Road CSO (052er) | Culverted tributary of River Blakewater via surface water surface | Not Discharging | 24:00 Jan 01 1970 | 23:52 Jan 18 |
| Merchants Landing Culvert St CSO | River Blakewater via the Culvert street culvert | Not Discharging | 14:48 Jan 05 | 23:52 Jan 18 |
| New Mill Street CSO | River Blakewater | Not Discharging | 07:13 Jan 01 | 23:52 Jan 18 |
| Notre Dame Gardens CSO | River Blakewater | Not Discharging | 19:36 Dec 31 2024 | 23:52 Jan 18 |
| Philips Road CSO | River Blakewater | Not Discharging | 23:40 Jan 06 | 23:52 Jan 18 |
| Philips Road CSO (052lo) | A culverted tributary of River Blakewater via surface water sewer | Not Discharging | 14:46 Jan 06 | 23:52 Jan 18 |
| Preston New Road | Tributary of Arley Brook | Not Discharging | 03:23 Jan 06 | 23:52 Jan 18 |
| Pringle Street CSO | Culverted tributary of River Blakewater | Not Discharging | 03:02 Dec 21 2024 | 23:52 Jan 18 |
| Queens Park Road CSO | Queens Park Culvert and then to the River Blakewater via surface water sewer | Not Discharging | 22:30 Jan 05 | 23:52 Jan 18 |
| Ramsgreave Drive CSO | Culverted tributary of the River Blakewater | Not Discharging | 23:00 Jan 14 | 23:52 Jan 18 |
| Revidge Rd/Preston New Rd Sso | Trubutary of Arley Brook | Not Discharging | 24:58 Jan 14 | 23:52 Jan 18 |
| Sharples Street CSO | Culverted tributary of River Darwen | Not Discharging | 24:08 Jan 17 | 23:52 Jan 18 |
| Thwaites Brewery Yard | River Blakewater | Not Discharging | 09:00 Jan 06 | 23:52 Jan 18 |
| Victoria Street CSO | Tributary of River Blakewater | Not Discharging | 04:50 Jan 01 | 23:52 Jan 18 |
| Wellington Road CSO | River Darwen | Not Discharging | 19:38 Dec 31 2024 | 23:52 Jan 18 |
| Whalley New Road CSO | River Blakewater | Not Discharging | 24:00 Jan 01 1970 | 23:52 Jan 18 |
| Whalley Old Rd/Providence St CSO | Little Harwood Brook | Not Discharging | 12:08 Jan 06 | 23:52 Jan 18 |
| Whalley Range / Wesley Street CSO | River Blakewater | Not Discharging | 10:02 Dec 03 2024 | 23:52 Jan 18 |
| Whalley Range/Grace Street CSO | River Blakewater | Not Discharging | 18:46 Dec 31 2024 | 23:52 Jan 18 |
| Whalley Range/Millham Street CSO | River Blakewater via surface water sewer | Not Discharging | 18:44 Dec 31 2024 | 23:52 Jan 18 |
| Witton Tanks CSO | River Blakewater | Not Discharging | 24:00 Jan 06 | 23:52 Jan 18 |