Conwy Marina through Menai Strait and The Swellies on one tide?

[Gazza]

I'm hoping that someone with local knowledge will be kind enough to give me some detail on whether we could leave Conwy Marina at the first opportunity on (probably) Thursday 31st August and, using the Penmean Swatch, get into the Strait as early as possible. I've worked out that it seems feasible (if tight) to get to The Swellies 2 hours before HW, which seems to be the best time.

However, I've seen a comment on the entry for Conwy in a port information site where a local has specifically stated that, unless you're in a fast power boat, it's not feasible. We're in a 33' yacht, so 5-6 knots is our maximum realistic speed. If all else fails, then waiting at Beaumaris until the next daylight tide seems the only option.

Any thoughts gratefully received.

 

[vyv_cox]

As you say, the ideal time to pass through the Swellies is at slack, two hours before HW Liverpool. However, if your trip is with the tide, as yours is, you can get through much later. I have gone north 1.5 hours before slack and south 1 hour after, although I know people who regularly go south 2 hours after. Can be a bit swirly on springs but following the directions you will have no problems.

 

[TSB240]

As Vyv says this is quite a normal trip for locals. We have been through on the ebb much much later than is recommended! If it's your first time don't! I think we recorded over 13 knots SOG when our 30 footer maxes out at 5 knots WOT. Ferry Gliding practice along the route was required. I don't think the boat ever pointed in the direction of travel for any of the transit. Any doubts pick up a vacant mooring or raft up to Prince Madog at MB. Don't bother with Beaumaris unless it is flat calm.

Passage plan Thursday

Gate opens 10.30 Ish? 16.00?

15 nm via swatch 3 hours max at 5 knots. You will get an advantageous tide from the swatchway to Menai bridge from about 10.00 so you will probably only take about 2 and a half hours maximum to do this trip!

Arrive Menai bridge 13.00. 18.30

Hw Swellies slack is 12.00 ish? 18.00 (proper neap tide now)

I doubt you will have more than a couple of knots of tide under you at that time as they are neaps and you will probably have a number of other boats for an escort.

Best spot to stop off is Port Dinorwic. Marina is cheap and is not silted uplike Caernarfon and has good food outlets locally. Alternatively moorings in Rowen Bay just south of Y Felinheli are free and very sheltered with a tidal back eddy that means a good nights sleep.

Enjoy Much more fun at Low Water!

Steve

 

[TSB240]

Oops that is this Thursday! Not the 31st! I will edit again! See second times added to previous post

 

[GrahamM376]

We've done from Conwy mooring, through Swellies and over the Bar lots of times on one tide but, you may be a bit pushed for time from the marina due to later departure. Have done Swellies up to slack +3 and not a problem if you are familiar with course.

 

[[3889]]

We've done from Conwy mooring, through Swellies and over the Bar lots of times on one tide but, you may be a bit pushed for time from the marina due to later departure. Have done Swellies up to slack +3 and not a problem if you are familiar with course.

My last 2 transits of the Swellies from Conwy were at LW slack (2m draft) . Leave late on the ebb (circa 9am on 31/8), go though Puffin sound as the flood starts and hang about at Menai Bridge until LW slack. Minimum depth on neaps was 3.5m though it's best to put a dog-leg into the normal transits to avoid Cheese rock (53d12.97N 4d10. 99W). I wouldn't do it without a plotter and check position accuracy passing under bridge and at Prices point.
I have done swellies at HW slack, leaving the marina as soon as the gate drops, but that was a few years ago and when I was there in April I gor the impression the gate opening times have been shortened since then.

 

[GrahamM376]

My last 2 transits of the Swellies from Conwy were at LW slack (2m draft) . Leave late on the ebb (circa 9am on 31/8), go though Puffin sound as the flood starts and hang about at Menai Bridge until LW slack. Minimum depth on neaps was 3.5m though it's best to put a dog-leg into the normal transits to avoid Cheese rock (53d12.97N 4d10. 99W). I wouldn't do it without a plotter and check position accuracy passing under bridge and at Prices point.
I have done swellies at HW slack, leaving the marina as soon as the gate drops, but that was a few years ago and when I was there in April I gor the impression the gate opening times have been shortened since then.

I always found the leading marks to be accurate enough and trust those rather than a plotter. Only got a bit fraught once when we were squeezed between the Waverley and Cribbin rock. Used to do Conwy down to France each summer for about 6 years so liked to clear over the bar on one tide (except in strong SW when we went the long way around) and then straight down south.

 

[TSB240]

Local knowledge.

Easiest way to avoid Cheese rock at low water is to turn sharp to starboard and aim for the base of the Electricity pylon on the Angelsey shore when you get to the concrete Pyramid at the end of the marked channel lay line.This takes you through deeper water and the centre of the other arch of the Bridge.

IMHO relying on plotter accuracy for Swellies especially at Low water could well and truly dent more than your pride!

Also don't rely on VHF contact with HHCG should you get into trouble as it is well known by locals as a big black hole for VHF on most craft. Mobile reception is fine!

 

[Gazza]

Many thanks for all the info. - it has certainly helped to put my mind at rest and, particularly as we will be at neaps, it looks like a runner.

Once again, thanks for the help.

 

[[3889]]

IMHO relying on plotter accuracy for Swellies especially at Low water could well and truly dent more than your pride!

/QUOTE]


Hence the precision checks. Out of interest, have you done a LW slack transit?

 

[TSB240]

Yes Many most recently last year on a spring tide with our draft of 1.09M squeeky bum time at Cribbin.
Low water slack is far more interesting as you actually get to see the bits you think you are avoiding at High Tide! My Great Uncle and Father introduced me to sailing the strait over 55 years ago. The late Howard Davies of the outward bound training school gave me a further understanding of the whole area including the Swellies when I was teenager.
I will not profess to knowing all the lumps intimately yet!

Have you considered the effect of loosing a couple of satellites on your accuracy from your pulpit mounted GPS as you lose a fair bit of "visible sky" at low tide in the gorge. I have spent more time than most in this area and will often see our boat position icon is well off the leading lines that I am following by mark one eyeball. In particular this is most obvious at the narrowest part of the transit alongside Cribbin just before the exit Pyramid. At high water this is really not a problem for shallow draft boats as the tip of Cribbin has between 4 foot of water at neaps and 11 foot at springs over the top of it.

Really this is about the only hidden obstruction that any yacht going through at high tide could hit other than the visible perch on Swelly rock! Swelly rock has abot 9-14 foot of water over the top of it and the Platters 14 to 21 feet!

A tip from my tutor was that if the Platters are covered then the passage around the other side of Gored Goch is as open as the mainland route! Indeed this is the preffered route that the Balmoral takes. Below is a link to a chart that the local pilots used and was developed by lead line surveys over a period of time by students at HMS Conway based locally at Plas Newydd. Take a close look at it.... The underlined soundings are not the usual drying heights found on modern charts but actual soundings at local HW spring.

http://www.hmsconway.org//RootFolder/Assets/Navigation/HTML_Doc/swelly_channel.htm

Glazebrook gave you even more options to try!

https://www.liverpool.ac.uk/~cmi/boat/swelly/gla04.jpg

Steve