Caernarfon Notice to Mariners 03/2026
Bar Caernarfon Bar
Aid to navigation Fairway Buoy L FL10s is now on station.
53° 06’.95 N 004°25’.14 W
David John O’Neill
Harbwr Feistr Caernarfon Harbour Master
Author: Austin Goudge
Conwy Notice to Mariners 06/2026
All mariners are advised that The Environment Agency/Briggs Marine are scheduled to undertake a small scale scientific survey (sediment grab sampling) between 1st June – 31st June 2026 in Conwy Bay and Red Wharf Bay from the vessel Severn Guardian.
- Date: 1st June – 31st June 2026. The surveys are likely to be done between 12th June to 15th June.
- Duration : 1 Day
- Activity: Day grabs at 2 locations in Conwy Bay/Estuary and 2 locations in Red Wharf Bay.
- Vessel: CSV Severn Guardian MMSI: 235091052 Callsign: 2FGL5 VHF: Ch. 16
- Skipper (Briggs Marine): Mark Wiliams ([email protected])
- Survey Officer (Environment Agency) : Richard Pritchard (richard[email protected])
Marine licence RML 2503, maps and locations all attached.
Conwy & Red Wharf Bay Benthic locations 2026
| Location | Site code | Easting | Northing | WGS84 Lat DD.DDDDDD | WGS84 Long DD.DDDDDD | WGS84 Lat DD°MM.MMMM’ | WGS84 Long DD°MM.MMMM’ |
|---|---|---|---|---|---|---|---|
| Conwy_Bay | CON016 | 273047 | 382188 | 53.32133865 | -3.90743041 | 53°19.2803’N | 3°54.4458’W |
| Conwy_Bay | CWC002 | 268484 | 380236 | 53.30269241 | -3.975095034 | 53°18.1615’N | 3°58.5057’W |
| Red_Wharf_Bay | RWB002 | 255770 | 382159 | 53.31665421 | -4.166613102 | 53°18.9993’N | 4°09.9968’W |
| Red_Wharf_Bay | RWB011 | 253734 | 383802 | 53.33085632 | -4.197908401 | 53°19.8514’N | 4°11.8745’W |
Maps
Conwy Notice to Mariners – Cultch deployment
Notice of Exempted Activities for scientific instruments
Connecting Conwy research project – Scientific monitoring
An underwater video survey will take place on 01 April 2026 (weather dependent) within the licensed area of licence Ref: DEML2284. A copy of the location and coordinates are below. The equipment will be deployed from Bangor University vessel, Macoma, over slack high water and recovered after 2 hours. The vessel will remain in the area throughout to monitor the equipment. The equipment will be marked with surface buoys. It should be noted that these are not for any navigational warning purposes.
Project Location
Project Coordinates
| Site | Latitude | Longitude |
|---|---|---|
| Area 1 | 53° 18.778 North | 3° 52.575 West |
| Area 2 | 53° 19.546 North | 3° 52.781 West |
Caernarfon Notice to Mariners – Benthic Survey 2
The Environment Agency/Briggs Marine are scheduled to undertake a small scale scientific survey (sediment grab sampling) from the vessel Severn Guardian.
Survey Details
Survey Period: 07/04/2026 – 23/04/2026
Survey duration: 1 day
Time on station: 15-60 mins
Survey Vessel: Severn Guardian
Skipper: Mark Williams
Survey Officer: Tom Lord [email protected]
| Station | OSGB36 Easting | OSGB36 Northing | OSGB36 OS Reference | WGS84 Lat DD.DDDDDD | WGS84 Long DD.DDDDD | WGS84 Lat DD°MM.MMM’M | WGS84 Long DD°MM.MMMM’ |
|---|---|---|---|---|---|---|---|
| Cefni_01 | 237443.7 | 364727.3 | SH 37444 64727 | 53.1547851 | -4.435267 | 53°09.2871’N | 4°25.9541’W |
| Cefni_02 | 238436 | 363340.4 | SH 38436 63340 | 53.1426315 | -4.4170494 | 53°08.5579’N | 4°25.0230’W |
| Cefni_03 | 238018.7 | 364197 | SH 38018 64197 | 53.1502037 | -4.423717 | 53°09.0122’N | 4°25.4230’W |
| Cefni_04 | 237972.5 | 363473.7 | SH 37972 63474 | 53.1436920 | -4.4240408 | 53°08.6215’N | 4°25.4424’W |
| Cefni_05 | 237378.2 | 364262.1 | SH 37378 64262 | 53.1505889 | -4.4333124 | 53°09.0353’N | 4°25.9987’W |
Caernarfon Notice to Mariners – Benthic Survey
The Environment Agency/Briggs Marine are scheduled to undertake a small scale scientific survey (sediment grab sampling) in the Caernarfon Bay area from the vessel Severn Guardian.
Survey Details
Survey Period: 07/04/2026 – 23/04/2026
Survey duration: 2 days
Time on station: 15-60 mins
Survey Vessel: Severn Guardian
Skipper: Mark Williams
Survey Officer: Tom Lord [email protected]
| Station | OSGB36 Easting | Northing | OSGB36 OS Reference | DD.DDDD DD | Long DD.DDDDD | DD°MM.MM MM’ | DD°MM.MM MM’ |
|---|---|---|---|---|---|---|---|
| CAERN_1 | 239280 | 361992 | SH 39280 61992 | 53.130783 | -4.403765 | 53°07.8470’N | 4°24.2261’W |
| CAERN_2 | 240832 | 361471 | SH 40832 61471 | 53.126572 | -4.380327 | 53°07.5943’N | 4°22.8196’W |
| CAERN_4 | 238263 | 360637 | SH 38263 60637 | 53.118366 | -4.406132 | 53°07.1019’N | 4°24.3679’W |
| CAERN_5 | 240341 | 357819 | SH 40341 57819 | 53.09366 | -4.385842 | 53°05.6172’N | 4°23.1506’W |
| CAERN_6 | 238946 | 357409 | SH 38946 57409 | 53.09043 | -4.406453 | 53°05.4258’N | 4°24.3872’W |
| CAERN_8 | 241276 | 353524 | SH 41276 53524 | 53.055325 | -4.369768 | 53°03.3195’N | 4°22.1861’W |
| CAERN_9 | 235278 | 358288 | SH 35278 58288 | 53.084604 | -4.451153 | 53°05.0762’N | 4°27.0692’W |
| CAERN_12 | 243950 | 347509 | SH 43950 47550 | 52.961015 | -4.421605 | 52°57.9408’N | 4°25.6606’W |
| CAERN_13 | 231147 | 348006 | SH 31147 48006 | 53.002663 | -4.517861 | 53°00.1598’N | 4°31.0741’W |
| CAERN_18 | 243907 | 360290 | SH 43907 60290 | 53.111536 | -4.401007 | 53°06.6922’N | 4°24.0604’W |
| CAERN_19 | 241302 | 359327 | SH 41302 59327 | 53.107452 | -4.372259 | 53°06.4471’N | 4°22.3369’W |
| CAERN_20 | 237878 | 361000 | SH 37878 61000 | 53.118084 | -4.453248 | 53°07.0850’N | 4°27.1949’W |
| CAERN_21 | 239993 | 355372 | SH 39993 55372 | 53.037578 | -4.480073 | 53°02.1467’N | 4°28.0047’W |
| CAERN_22 | 238150 | 351600 | SH 38150 51600 | 53.053778 | -4.480079 | 53°03.1467’N | 4°28.0047’W |
| CAERN_23 | 242151 | 342151 | SH 42251 42151 | 52.949333 | -4.423998 | 52°56.9600’N | 4°23.9985’W |
| CAERN_24 | 228285 | 341382 | SH 22825 41382 | 52.942268 | -4.559601 | 52°56.5361’N | 4°33.4176’W |
Caernarfon Notice to Mariners 02/2026
Aid to navigation Port No C2 Fl.R 10s is on its appropriate station.
53° 07’.17 N 004°24’.32 W
David John O’Neill
Harbwr Feistr Caernarfon Harbour Master
Menai Bridge Notice to Mariners 01/2026
Mariners are advised that between 8 March 2026 and 14 March 2026 there will be heightened commercial vessel traffic operating in the area identified on the above chart, particularly during periods around low water slack.
This traffic will include barges and seagoing tugs which may need to hold sta on for extended periods. All vessels and barges will be displaying the appropriate day shapes or lights.
Mariners should navigate with caution and maintain a safe distance from the vessels. If in any doubt, mariners should make contact with the standby vessel Delta2 on VHF Channel 16.
Overnight, large vessels will be anchored in the vicinity of the marked ‘X’, displaying the required anchor lights.
For press enquiries: Press Office – UK Highways: Call 0844 693 1448 – this is a 24/7 number. Journalists are requested not to contact individual departments. The Press Office will assist and arrange an appropriate spokesperson if required and may be contacted on 01248 752130 or 01248 752128.
This notices self-cancels at 11:59pm on 14 March 2026.
Harbwr Feistr Porthaethwy/ Menai Bridge Harbormaster
Ebost/Email: [email protected]
Caernarfon Notice to Mariners 01/2026
Aid to navigation C2 is not on its appropriate station.
53° 07’.13′ N 004° 24’.35 W
Mariners are advised to exercise caution in this area.
David John O’Neill
Harbwr Feistr Caernarfon Harbour Master
Conwy Notice to Mariners 05/2026
All mariners are advised that dredging operations will commence at Deganwy Marina on 01/03/2026. Dredging is carried out in accordance with marine licence DML 2322. A further Local Notice to Mariners will be issued advising the position of the lit outfall mark once the mark is laid.
Matthew Forbes
MSc LLB (hons) BSc AFNI
Conwy Harbour Master
Conwy Notice to Mariners 04/2026
All mariners are advised that Local Notice To Mariners 03/2026 is hereby cancelled. Navigation mark C11 in the Conwy Harbour approach channel is now on station and lit.
Matthew Forbes
MSc LLB (hons) BSc AFNI
Conwy Harbour Master