| 293 Preston Old Road CSO (052m0) | River Blakewater | Not Discharging | 24:00 Jan 01 1970 | 04:02 Jul 31 |
| 293 Preston Old Road CSO (052m0) | River Darwen | Not Discharging | 21:16 Jul 16 | 04:02 Jul 31 |
| Accrington Road CSO | Culverted section of Knuzden Brook | Not Discharging | 17:32 Jul 15 | 04:02 Jul 31 |
| Addison Close CSO | River Blakewater a tributary of the River Darwen | Not Discharging | 16:16 Jul 15 | 04:02 Jul 31 |
| Apple Street CSO | River Blakewater | Not Discharging | 15:58 Jul 15 | 04:02 Jul 31 |
| Appleby Sreett CSO | Culverted tributary of the River Blakewater, a tributary of the River Darwen | Not Discharging | 16:18 Jul 15 | 04:02 Jul 31 |
| Aqueduct Road CSO | River Darwen | Not Discharging | 23:07 Jul 06 | 04:02 Jul 31 |
| Back Queens Park Rd | Culverted Tributary of River Blakewater | Not Discharging | 07:30 Dec 20 2024 | 04:02 Jul 31 |
| Beechwood Road CSO | River Blakewater | Not Discharging | 11:12 Jul 30 | 04:02 Jul 31 |
| Bolton Road Combined Sewer Overflow | River Darwen | Not Discharging | 18:00 Jul 15 | 04:02 Jul 31 |
| Brownhill Drive CSO | Culverted Tributary of River Blakewater | Not Discharging | 10:50 Jun 23 | 04:02 Jul 31 |
| Cherry Tree Works Site | River Darwen | Not Discharging | 03:30 Jul 31 | 04:02 Jul 31 |
| Cumberland Street CSO | Queens Park Culvert (Tributary of River Blakewater) | Not Discharging | 16:10 Jul 15 | 04:02 Jul 31 |
| Daisy Lane CSO | River Blakewater | Not Discharging | 24:00 Jan 01 1970 | 04:02 Jul 31 |
| Dickens Street CSO | Queens Park Culvert (tributary of River Blakewater) | Not Discharging | 23:06 Jul 06 | 04:02 Jul 31 |
| Dukes Brow CSO | River Blakewater | Not Discharging | 16:00 Jul 15 | 04:02 Jul 31 |
| Fielden Street CSO | River Blakewater, a tributary of the River Darwen | Not Discharging | 03:22 Jan 30 | 04:02 Jul 31 |
| Gate Street CSO | Culverted tributary of River Blakewater | Not Discharging | 16:06 Jul 15 | 04:02 Jul 31 |
| Gorse St Combined Sewer Overflow | River Darwen | Not Discharging | 23:12 Jul 15 | 04:02 Jul 31 |
| Great Bolton Street CSO | River Blakewater | Not Discharging | 11:06 Feb 03 | 04:02 Jul 31 |
| Grimshaw Park CSO | Culverted section of an unnamed trib. of River Blakewater | Not Discharging | 20:18 Jul 22 | 04:02 Jul 31 |
| Infirmary Street CSO 05050 | Leeds Liverpool Canal | Not Discharging | 02:24 Jan 01 | 04:02 Jul 31 |
| Lark Hill/Brookhouse Lane CSO | Culverted tributary of River Blakewater | Not Discharging | 17:00 Jul 29 | 04:02 Jul 31 |
| Lower Audley CSO | Culverted tributary of River Blakewater | Not Discharging | 23:30 Jul 06 | 04:02 Jul 31 |
| Manor Road CSO (052er) | Culverted tributary of River Blakewater via surface water surface | Not Discharging | 21:30 Jul 06 | 04:02 Jul 31 |
| Merchants Landing Culvert St CSO | River Blakewater via the Culvert street culvert | Not Discharging | 13:34 May 28 | 04:02 Jul 31 |
| New Mill Street CSO | River Blakewater | Not Discharging | 07:48 Apr 10 | 04:02 Jul 31 |
| Notre Dame Gardens CSO | River Blakewater | Not Discharging | 19:36 Dec 31 2024 | 04:02 Jul 31 |
| Philips Road CSO | River Blakewater | Not Discharging | 24:10 Jul 07 | 04:02 Jul 31 |
| Philips Road CSO (052lo) | A culverted tributary of River Blakewater via surface water sewer | Not Discharging | 18:50 Jul 20 | 04:02 Jul 31 |
| Preston New Road | Tributary of Arley Brook | Not Discharging | 08:27 Jul 23 | 04:02 Jul 31 |
| Pringle Street CSO | Culverted tributary of River Blakewater | Not Discharging | 16:00 Jul 15 | 04:02 Jul 31 |
| Queens Park Road CSO | Queens Park Culvert and then to the River Blakewater via surface water sewer | Not Discharging | 16:12 Jul 15 | 04:02 Jul 31 |
| Ramsgreave Drive CSO | Culverted tributary of the River Blakewater | Not Discharging | 08:04 Jul 30 | 04:02 Jul 31 |
| Revidge Rd/Preston New Rd Sso | Trubutary of Arley Brook | Not Discharging | 12:52 Jun 02 | 04:02 Jul 31 |
| Sharples Street CSO | Culverted tributary of River Darwen | Not Discharging | 22:12 Jul 23 | 04:02 Jul 31 |
| Thwaites Brewery Yard | River Blakewater | Not Discharging | 16:26 Jul 15 | 04:02 Jul 31 |
| Victoria Street CSO | Tributary of River Blakewater | Not Discharging | 16:02 Jul 15 | 04:02 Jul 31 |
| Wellington Road CSO | River Darwen | Not Discharging | 21:24 Jul 22 | 04:02 Jul 31 |
| Whalley New Road CSO | River Blakewater | Not Discharging | 15:58 Jul 15 | 04:02 Jul 31 |
| Whalley Old Rd/Providence St CSO | Little Harwood Brook | Not Discharging | 18:40 Jul 20 | 04:02 Jul 31 |
| Whalley Range / Wesley Street CSO | River Blakewater | Not Discharging | 10:02 Dec 03 2024 | 04:02 Jul 31 |
| Whalley Range/Grace Street CSO | River Blakewater | Not Discharging | 16:00 Jul 15 | 04:02 Jul 31 |
| Whalley Range/Millham Street CSO | River Blakewater via surface water sewer | Not Discharging | 16:02 Jul 15 | 04:02 Jul 31 |
| Witton Tanks CSO | River Blakewater | Not Discharging | 16:28 Jul 15 | 04:02 Jul 31 |