Caernarfon Notice to Mariners 19/2025

Mariners are advised of the current positions of the Aids to Navigation listed below.

Yellow Highlight =Change of position since last
Aid to NavigationDepth
(5 metres off correct
side of AtoN,
adjusted to CD).
LatitudeLongitudeLight
LLANDDWYN ISLAND
SW ROCK BUOY
S CARDINAL
8.5m53ᵒ 07’.89 N004ᵒ25’.15 WUnlit
LLANDDWYN ISLAND
NE ROCK BUOY
S CARDINAL
2.02m53ᵒ 08’.04 N004ᵒ24’.47 WUnlit
SAFE WATER MARK7.64m53ᵒ 06’.95 N004ᵒ25′.14 WL Fl.10s
C 1 STARBOARD5.38m53ᵒ 06’.96 N004ᵒ24’.71 WFl.G.5s
C 2 PORT0.34m53ᵒ 07’.12N004ᵒ24’.71 WFl.R.10s
C 3 STARBOARD1.7m53ᵒ 07’.23 N004ᵒ 23’.88 WQ.G
C 4 PORT1.8m53ᵒ 07’.12 N004ᵒ22’.72 WQ.R
GRAMPIAN CASTLE
S CARDINAL
N/A53ᵒ 07’.26 N004ᵒ 22’.96 WVQ(6)+LFl.10s
C 5 STARBOARD1.93m53ᵒ 07’.19 N004ᵒ23’.37 WFl.G(2).5s
C 6 PORT2.3m53ᵒ 07’.16 N004ᵒ21’.91 WFl.R.5s
MUSSEL BANK PERCH5.59m53ᵒ 07’.32 N004ᵒ20’.92 WFl.R(2).5s
C 8 PORT3.76m53ᵒ 07’.63N004ᵒ19’.43 WFl.R.3s
C 10 PORT2.1m53ᵒ 07’.95 N004ᵒ18’.22 WQ.R
C 7 STARBOARD2.3m53ᵒ 08’.14 N004ᵒ18’.13 WQ.G
C 12 PORT3.03m53ᵒ 08’.50 N004ᵒ17’.38 WFl(2)R.10s
C 9 STARBOARD3.58m53ᵒ 08’.57 N004ᵒ16’.88 WFl.G.2s
CHANGE BUOY
S CARDINAL
2.19m on station
6.09m in channel
53ᵒ 08’.81 N004ᵒ16’.72 WVQ(6)+LFl.10s
SEIONT RIVER
BIFURCATION
-1.21m53ᵒ 08’.55 N004ᵒ16’.79 WUnlit
TRAETH GWYLLT
STARBOARD
6.04m53ᵒ 09’.29 N004ᵒ16’.08 WFl(2)G.10s
C 13 STARBOARD3.74m53ᵒ 09’.54 N004ᵒ15’.89 WFl(4)G.10s
C 11 STARBOARD4.2m53ᵒ 09’.88 N004ᵒ15’.63 WFl(2)G.5s
C 14 PORT7.38m53ᵒ 10’.23 N004ᵒ15’.41 WFl.R.5s
C TEMP53ᵒ 10’.53 N004ᵒ14’.67 WFL(2)R.5s
C 9 STARBOARD
PORT DINORWIC
1.29m53ᵒ 10.69 N004ᵒ13’.81 WFL(3)G.10s

David John O’Neill
Harbwr Feistr Caernarfon Harbour Master

Conwy Notice to Mariners 15/2025

Notice of Commencement of Works- Oyster deployment

Wild Oysters: Conwy Bay Project – Native oyster (Ostrea edulis) Habitat Restoration, Conwy Bay.

The deposit of native oysters, Ostrea edulis for Wild Oysters: Conwy Bay Project is due to take place between 17 June 2025 until 24 June 2025. The works will involve depositing oysters on the seabed undertaken by the Conwy Harbour Authority, using the vessel Jac-Y-Do. Temporary buoys will be in place to aid deployment within the site. It should be noted that these are not for any navigational warning purposes.

See the attached document for more information.

Matthew Forbes
MSc LLB (hons) BSc AFNI
Conwy Harbour Master

Conwy Notice to Mariners 14/2025

All mariners are advised that 4 orange buoys will be positioned in Conwy bay to aid in the cultch deployment for the Bangor University oyster regeneration project. Please see attached detailed information of the planned cultch deployment works issued by Bangor University.

Works are scheduled to commence on the 9 th June 2025 for a period of 20 days.

A further notification will be issued on completion of the Cultch deployment.

Matthew Forbes
MSc LLB (hons) BSc AFNI
Conwy Harbour Master

Caernarfon Notice to Mariners 15/2025

Notice of temporary restriction to enter or depart the Afon Seiont. due to mechanical failure of the Aber Bridge.

The bridge is not mechanically able to open for vessels. Emergency work will be completed as soon as possible. Once the bridge is repaired a cancellation notice will be issued.

For vessel requiring safe haven. Please make contact with the Dock Master. Ch 80. 01286 672346

David John O’Neill
Harbwr Feistr Caernarfon Harbour Master

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