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Local Notice to Mariners 20/2023
29/11/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Mae cymhorthydd mordwyo Port Rhif C2 Fl. R 10s nawr ar ei safle priodol.
53ᵒ07.14′ Gog 004ᵒ24.38′ Gor
Cynghorir morwyr fod Rhybudd Morwriath Lleol 18/2023 nawr wedi’i ganslo.
Aid to navigation Port No C2 Fl. R 10s is now on its appropriate station.
53ᵒ07.14′ N 004ᵒ24.38′ W
Mariners are advised that Notice to Mariners 18/2023 in now cancelled.
Local Notice to Mariners 19/2023
29/11/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Mae cymhorthydd mordwyo Starbord Rhif C1 Fl G 5s nawr ar ei safle priodol.
53ᵒ07.06′ Gog 004ᵒ24.67′ Gor
Cynghorir morwyr fod Rhybudd Morwriath Lleol 17/2023 nawr wedi’i ganslo.
Aid to navigation Starboard No C1 Fl G 5s is now on its appropriate station.
53ᵒ07.06′ N 004ᵒ24.67′ W
Mariners are advised that Notice to Mariners 17/2023 in now cancelled.
Local Notice to Mariners 18/2023
21/11/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Nid yw cymhorthydd mordwyo Port Rhif C2 Fl. R 10s nawr ar ei safle priodol.
53ᵒ07.14′ Gog 004ᵒ24.38′ Gor
Aid to navigation Port No C2 Fl. R 10s is NOT on its Station appropriate station.
53ᵒ07.14′ N 004ᵒ24.38′ W
Local Notice to Mariners 17/2023
13/11/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Nid yw cymhorthydd mordwyo Starbord Rhif C1 Fl G 5s ar ei safle priodol.
53ᵒ07.06′ Gog 004ᵒ24.67′ Gor
Aid to navigation Starboard No C1 Fl G 5s is NOT on its Station appropriate station.
53ᵒ07.06′ N 004ᵒ24.67′ W
Local Notice to Mariners 16/2023
06/10/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Nid yw cymhorthydd mordwyo Bwi Tramwyo L FL 10s ar ei safle priodol.
53ᵒ06.95′ Gog 004ᵒ25.14′ Gor
Mae’r cymhorthydd mordwyo wedi derfynwyd dros dro ar gyfer y gaeaf.
Aid to navigation Fairway Buoy L FL10s is not on station.
53ᵒ06.95′ N 004ᵒ25.146′ W
The Aid to navigation has been temporarily discontinued for the winter.
Local Notice to Mariners 15/2023
06/10/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Ynys Llanddwyn Island
Mae cymhorthydd mordwyo “Graig Gogledd-ddwyrain” Ynys Llanddwyn Cardinal De, Melyn a Du ar ei safle priodol.
53ᵒ08.04′ Gog 004ᵒ24.47′ Gor
Aid to navigation Llanddwyn Island “North East Rock” South Cardinal, Y.B is now on
its appropriate station.
53ᵒ08.04′ N 004ᵒ24.47′ W
Local Notice to Mariners 14/2023
23/09/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Ynys Llanddwyn Island
Nid iw cymhorthydd mordwyo “Graig Dde Dwyrain” Ynys Llanddwyn Cardinal De, Melyn a Du ar ei safle priodol.
53ᵒ08.04′ Gog 004ᵒ24.46′ Gor
Cynghorir morwyr i fod yn ofalus iawn yn y ardal hwn.
Aid to navigation Llanddwyn Island “South East Rock” South Cardinal, Y.B is not on its appropriate station.
53ᵒ08.04′ N 004ᵒ24.46′ W
Mariners are advised to exercise extreme caution in this area.
Local Notice to Mariners 13/2023
31/08/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Cynghorir morwyr mae’r cymhorthydd mordwyo Starbord Rhif C1 nawr wedi goleu.
53ᵒ07.06′ Gog 004ᵒ24.67′ Gor
Aid to navigation Starboard No C1 is now lit
53ᵒ07.06′ N 004ᵒ24.67′ W
Local Notice to Mariners 12/2023
25/08/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Cynghorir morwyr mae’r cymhorthydd mordwyo Starbord Rhif C1 heb golau.
Cynghorir morwyr i fordwyo gyda gofal yn yr ardal hon.
53ᵒ07.06′ Gog 004ᵒ24.67′ Gor
Aid to navigation Starboard No C1 is unlit
Mariners are advised to navigate with caution in this area.
53ᵒ07.06′ N 004ᵒ24.67′ W
Local Notice to Mariners 11/2023
15/08/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Caernarfon
Ar ddydd Sadwrn 19 a dydd Sul 20 o Awst Mae Harbwr Caernarfon yn cynnal y OCRDA Rasio Cychod Pŵer.
Cynghorir Morwyr y bydd rasio cychod pŵer yn yr ardal tu allan i’r Afon Seiont a Doc Fictoria. Bydd oedi posibl mewn gall llywio i mewn ac allan o’r Afon Seiont
a Doc Fictoria. Byddwch yn amyneddgar a dilynwch geisiadau’r swyddogion os gwellwch yn dda.
Mae mordwyo y tu mewn i’r ardal GLAS yn gwahardd yn llym yn ystod yr amseroedd rasio.
Cysylltwch â Meistr Doc am ragor o wybodaeth ar y diwrnodau rasio. VHF ch 80.
Gwelwch y PDF am y manylion
On Saturday the 19th and Sunday the 20th of August Caernarfon Harbour is hosting the OCRDA Powerboat racing.
Mariners are advised that there will be Powerboat and Jest ski racing in the area outside the River Seiont and Victoria Dock There will be potential delays in being able to navigate inbound and outbound of both the River Seiont and the Victoria Dock. Please be patient and follow the official’s requests.
Navigation inside the BLUE area is strictly prohibited during the racing times.
Please contact the Dock Master on VHF ch80 for further info on the race days.
Mariners are advised to exercise extreme caution in this area.
See PDF for full details
Local Notice to Mariners 10/2023
04/08/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Doc Fictoria – Victoria Dock
Hysbysir morwyr na fydd y Gât Llanw yn Doc Victoria yn cael ei weithredu oherwydd Gwaith yn gael ei neud ar y giat ar bore Dydd Iau 07:00-08:42BST 10/08/2023.
Fydd y giat ar agor pnawn Dydd Iau fel rheol 15:22-21:13BST
Ar gyfer pob symudiadau cychod sy’n ymwneud â’r Doc, cysylltwch â Meistr y Doc ar dm@caernarfonharbour.org.uk
Bydd yr Hysbysiad hwn i forwyr yn dod i ben 15:22 ar 10/08/2023.
Mariners are advised that the Tidal Gate in Dock Victoria will not be operated on Thursday morning (10/08/2023) 07:00-08:42 to allow necessary work to be carried out.
The gate will only be closed for the morning tide. The gate will be operational as normal on the evening tide 15:22-21:13. 10/08/2023
For all vessels movement relating to the Dock please contact the Dock Master on dm@caernarfonharbour.org.uk
This Notice to mariners will expire 15:22 on the 10/08/2023.
Local Notice to Mariners 09/2023
04/06/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Doc Fictoria – Victoria Dock
Hysbysir morwyr na fydd y Gât Llanw yn Noc Victoria yn cael ei weithredu oherwydd methiant Gât.
Nid oes unrhyw gychod wedi’u hawdurdodi i fynd i mewn nac allan o’r Doc heb gysylltu â Meistr y Doc yn gyntaf.
Ar gyfer pob symudiad cychod sy’n ymwneud â’r Doc, cysylltwch â Meistr y Doc ar dm@caernarfonharbour.org.uk
Bydd yr Hysbysiad hwn i forwyr yn dod i ben ar 11/06/2023 os bydd angen, bydd Hysbysiad pellach i Forwyr yn cael ei gyhoeddi ar 11/06/2023.
Mariners are advised that until further notice the Tidal Gate in Dock Victoria will not be operated due to a gate failure.
No vessels are authorised to enter or exit the Dock without first making contact with the Dock Master.
For all vessels movement relating to the Dock please contact the Dock master on dm@caernarfonharbour.org.uk
This Notice to Mariners will expire on the 11/06/2023, if required a further Notice to Mariners will be issued on the 11/06/2023
Local Notice to Mariners 08/2023
25/05/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Ni iw cymhorthydd mordwyo “Graig Gogledd-ddwyrain” Ynys Llanddwyn Cardinal De, Melyn a Du ar ei safle priodol.
53ᵒ08.04′ Gog 004ᵒ24.47′ Gor
Cynghorir morwyr i fod yn ofalus iawn yn y ardal hwn.
Aid to navigation Llanddwyn Island “North East Rock” South Cardinal, Y.B is off station.
53ᵒ08.04′ N 004ᵒ24.47′ W
Mariners are advised to exercise extreme caution in this area.
Local Notice to Mariners 07/2023
24/05/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Mae cymhorthydd mordwyo Bwi Tramwyo L FL 10s ar ei safle priodol.
53ᵒ06.95′ Gog 004ᵒ25.14′ Gor
Cynghorir morwyr fod Rhybudd Morwriath Lleol 05/2023 nawr wedi’i ganslo.
Aid to navigation Fairway Buoy L FL10s is now on station.
53ᵒ06.95′ N 004ᵒ25.14′ W
Mariners are advised that Notice to Mariners 05/2023 in now cancelled.
Local Notice to Mariners 06/2023
20/04/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Mae cymhorthydd mordwyo Bwi Drylliad dros dro yn nodi Castell Grampian Fl (4) Y10s ar ei safle priodol.
53ᵒ07.26′ Gog 004ᵒ22.96′ Gor
Y safle siartredig llongddrylliadau yw 53̊ 07’.30 Gog 004̊ 22’.98 Gor
Aid to Navigation Temporary Wreck Buoy marking the Grampian Castle Fl(4) Y10s is not on station.
53ᵒ07.26′ N 004ᵒ22.96′ W
The Wrecks charted position is 53̊ 07’.30 N 004̊ 22’.98 W
Local Notice to Mariners 05/2023
20/04/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Mae cymhorthydd mordwyo Bwi Tramwyo L FL 10s ar ei safle priodol.
53ᵒ06.95′ Gog 004ᵒ25.11′ Gor
Aid to navigation Fairway Buoy L FL10s is now on station.
53ᵒ06.95′ N 004ᵒ25.11′ W
Local Notice to Mariners 04/2023
20/04/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Mae cymhorthydd mordwyo Port Rhif C8 Fl R 3s ar ei safle priodol.
53ᵒ07.62′ Gog 004ᵒ19.45′ Gor
Aid to navigation Port No C8 Fl R 3s is on its appropriate station.
53ᵒ07.62′ N 004ᵒ19.45′ W
Local Notice to Mariners 03/2023
20/04/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Mae cymhorthydd mordwyo Starboard rhif C3 Q.G nawr ar ei safle priodol.
53ᵒ07.19′ Gog 004ᵒ23.84′ Gor
Aid to Navigation Starboard No C3 Q.G is now on its appropriate station.
53ᵒ09.19′ N 004ᵒ23.84′ W
Local Notice to Mariners 02/2023
20/04/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Mae cymhorthydd mordwyo Port Rhif C2 Fl. R 10s nawr ar ei safle priodol.
53ᵒ07.14′ Gog 004ᵒ24.38′ Gor
Aid to navigation Port No C2 Fl. R 10s is on its appropriate station.
53ᵒ07.14′ N 004ᵒ24.38′ W
Local Notice to Mariners 01/2023
20/04/2023 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Bar Caernarfon Bar
Mae cymhorthydd mordwyo Starbord Rhif C1 Fl G 5s ar ei safle priodol.
53ᵒ07.06′ Gog 004ᵒ24.67′ Gor
Aid to navigation Starboard No C1 Fl G 5s is on its appropriate station.
53ᵒ07.06′ N 004ᵒ24.67′ W
Longterm Notices to Mariners
Local Notice to Mariners 19/2021
02/07/2021 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Cynghorir morwyr bod yr ardal a amlygir isod ar y siart, yn benodol o amgylch C7 ac C12 wedi datblygu banc tywod sydd rhyw 1 metr yn uwch na Chart Datwm.
Cynghorir morwyr i gymryd rhybudd a rhoi sylw dyledus i’r dyfnder dŵr sydd ar gael wrth fordwyo yn yr ardal hon.

Mariners are advised that the area highlighted below on the chart, specifically around C7 and C12 has developed a sand bank that is approximately 1 meters above Chart Datum.
Mariners are advised to take caution and have due regard for the available depth of water when navigating in this area.
Local Notice to Mariners 12/2021
01/04/2021 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Harbour Master’s General Direction
5 Knot Speed Limit
By virtue of the provisions of Sec. 52 Harbour, Docks and Piers Clauses Act 1847, Port and harbour of Caernarfon Harbour Master has made the following General Direction:
1. This Direction is given to Masters (see note a) and persons having command or charge of any vessel (see note b) other than those vessels listed in paragraph 4(i) to 4(v).
2. This Direction applies at all times and in the area north of the existing and active speed limit at Y Felinheli. (Now known as the “Y Felinheli to Garreg Ginnog” Area of General Direction). The “Y Felinheli to Garreg Ginnog” means the area below the level of mean high water spring tides bounded by a line drawn along the northern extent of the existing charted speed limit at Y Felinheli and through to a new line drawn from a point 53ᵒ12.30’N 004ᵒ12.44’W to a point 53ᵒ12.40’ N 044ᵒ12.82’W. (Illustrative chart extract at end of NtoM).
3. At the Northern and Southern extent of the entire speed limit. Special Marks will be positioned to demark the area.
4. This Direction is not given to Masters and persons having command or charge of vessels:
(i) used by search and rescue organisations
(ii) of the Caernarfon Harbour Authority
(iii) of HM Customs and Excise
(iv) vessels under sail.
(v) used as safety boats by Yacht and Sailing Clubs and other such organisations when engaged in operations where complying with this Direction would inhibit their ability to fulfil their function as a safety boat
5. No vessel, except those listed in paragraphs 4(i) to 4(v), shall proceed at a speed of greater than 5 knots.
6. This Direction is given notwithstanding the requirements of the International Regulations for Preventing Collisions at Sea (see note c) and The Port and Harbour of Caernarfon Bylaws 1991 (see note d).
7. Not to comply with this Direction is a criminal offence for which the person having command or charge of the vessel may be prosecuted (see note e).
8. The Harbour Master or his deputies will be actively monitoring the compliance with this General Direction.
David John O’Neill
Caernarfon Harbour Master
Notes
a Sec.3 Harbour, Docks and Pier Clauses Act 1847
b As defined in the Port and Harbour of Caernarfon Bylaws 1991.
c Merchant Shipping (Distress Signals and Prevention of Collisions) Regulations 1996 [SI 75/1996]
d Port and Harbour of Caernarfon Bylaws 1991.
e Sec.3 and Sec.53 Harbour, Docks and Piers Clauses Act 1847
Owners, Agents Charterers, Marinas, Yacht Clubs and Recreational Sailing Organisations should ensure that the contents of this Notice are made known to the master or persons in charge of their vessel or craft.
Blue area denotes existing speed limit. Yellow area denotes new area of General Direction.
Local Notice to Mariners 14/2019
16/05/2019 – Y Fenai – Siart 1464 – Menai Strait – Chart 1464
Menai Strait
Cynghorir morwyr bod yr ardal a amlygir isod ar y siart, yn benodol o C11 er i C9 wedi datblygu banc tywod sydd rhyw 0.5 metr o ddŵr yn is na Chart Datwm.
Cynghorir morwyr i gymryd rhybudd a rhoi sylw dyledus i’r dyfnder dŵr sydd ar gael wrth fordwyo yn yr ardal hon.
Mariners are advised that the area highlighted below on the chart, specifically from C11 though to C9 has developed a sand bank that has approximately 0.5 meters of water below Chart Datum.
Mariners are advised to take caution and have due regard for the available depth of water when navigating in this area.