Swansea to Portishead - Advice needed please (copied from Scuttlebutt)

[Achillesheel]

It's been suggested that I should move this request to this forum from Scuttlebutt:-

I was asked this morning about sailing on the Bristol Channel. An acquaintance has been asked to deliver a Westerly Griffon from Swansea to Portishead one day in June, probably around the 26th; he is a YM, but his sailing experience is mainly in the Solent.

He asked me because he’d heard that I have sailed on the Bristol Channel, but my experience is only on a Laser at Portishead Sailing Club, so I couldn’t really help.

I told my acquaintance that the YM Scuttlebutt forum is a great source of wisdom and experience, but it takes a while to be registered, so I said I would post this on his behalf.

Any advice on the best time to leave, how long the passage might take, any hazards to avoid, would be greatly appreciated.
Read more at http://www.ybw.com/forums/showthrea...-Portishead-Advice-needed#ViMKHi9QPMKCA1sI.99

 

[Yellow Ballad]

I'll copy my reply here so other can build on it.

I did Oxwich Bay to Newport for the first time the other week, similar distance to Portishead. I had planned on stopping at Barry or Cardiff but it was such a quick and easy trip I carried on to Newport and got there with 2 hours of tide to go (you gain an hour of tide going up channel). I left 2 hours before LW Swansea as the winds were light, I ended up motoring till the wind filled but it got me a bit futher up when the tide changed. I believe there's an anticlockwise eddy in Swansea bay so leaving a bit earlier might be a worthwhile thing so you don't fight it. Getting through Nash Passage I can't comment, some say it's fine other avoid it at all costs. He might want to nip out before.

Wolves rock nead Cardiff is one to keep clear as well as any Grounds (Swansea/Cardiff). The run up from Cardiff to Portishead is fine but there are shipping channels Avonmouth like you to keep clear. I had a horrible windshift (goosewinged to none and then a beat off Lavernock Spit/Ranny, the tide ripping through didn't help. Heading through the Holmes might help with the wind but it can get lumpy round there.

Also look behind for ships, they come out of nowhere!

 

[vodzurk]

Newbie Mobo owner based at Portishead, so might not be entirely relevant to sailing...

I'd put a phonecall in on the morning to Bristol VTS - 01179 802638, or channel 12 callsign "Bristol VTS"... and take note of any traffic and their anticipated timings / direction. As Yellow Ballad says, they can sneak up on you, and they aren't able to maneuver very well in the "Kings Road" due to their draft.

Again, as Yellow Ballad says, watch out for Wolves Rock... someone got stuck on it last year.

Personally, approaching from Wales, I now stick North/West of the Holms to avoid unanticipated lumps that have caught us out when going between Steep+Flat Holm. We're only 21", so lumps aren't great for us.

Obviously... don't go against the tide unless you're motoring... It can easily push against you with 5mph, and I swear I've seen eddies doing 15mph... though that's debatable .

Also keep an eye on how much water you've got under, as large parts dry out. We use Navionics and it's always kept us safe so far (along with a paper backup to note the markers).

Portishead Marina website (link) has oodles of details on it, including pilotage info.

Oooh, don't miss the lock in! Your draft might mean you can't use the first/final ones too, might be worth checking.

Edit: Just remembered... be aware of wind blowing from south-westerly direction, especially over tide... it can really jack the waves up.

 

[Tamar]

Wolves won't be a problem on a rising tide, by the time you get in the vicinity they will be well covered,as will most of the sand banks past Cardiff.
Edit

 

[mattonthesea]

Did this on Saturday

Useful to have AIS or a good look out

If calm:

turn left out of Swansea and go up through Nash Passage. Keep a good eye out here with your own pilot plan in hand to avoid the reefs. But it gets nasty in adverse weather

Planned speed: 5 kts - leave around low water depending on your depth (Swansea is shallow at low tide springs). At 6 kts you could probably leave it until just after low water.


If wind stronger and with West or South wind:

keep straight our of Swansea until you can round the cardinal at the west end of the reefs. Then east

Planned speed:

5kts - leave Swansea 2 hours before low tide - the tide will be in your favour to the cardinal and then against you for a while and then with you as you approach Nash Point. It's like 'Warp Factor 7 Mr Zulu' as it turns. At springs you could be doing up to 10 kts SOG easily as you approach Steep and Flat Holme


If wind is from east or north and stronger then you're in for a choppy ride - I wouldn't. The wind over tide effect is much more pronounced in the Bristol Channel. I have spent an hour surfing in a 32ft boat and staying still with wind over tide whilst waiting for the tide to turn. Pooped on three occasions!

Several commercial ports on south coast of Wales and two either side of river Avon so sometimes makes Solent look a bit quiet Keep to the edge or out of the channel but be aware that ships don't always keep to it. Monitor CH12 once passed the Holmes and don't be afraid to ask Bristol VTS about traffic. They are usually friendly and the commercial traffic will then be aware of you. On Sat I agreed port to port with one ship as we were on a collision course; but I was surprised that he was happy to be on 30m away! We were about half a mile outside the channel at that point. Useful info at http://gloucesterharbourtrustees.or...al-Craft-Navigation-Guidelines_download-1.pdf

With the tidal range you can cut a lot of the corner off going up but do be aware of the changing depths around English Banks. If you go up the west/north side of the channel be aware that it takes a mile or two to cross back to the Portishead side because of the tidal speed. Portishead has an eddy that slows you down as you approach very close to Portishead Point. and you can turn into the bay to take sails down etc. 24 hour lock for the marina but it all but dries. You;ll be getting there an hour or so before high water so no problem.

Safe Havens: very little on south side! North side there is not much more but the commercial ports will take you in emergency. Barry and Cardiff are your main choices. I have hourly waypoints marked to check on progress. I use the ones past Cardiff as decision points: to turn in there or keep going.

Hope this doesn't put you off! It's quite a fun passage but you do need to keep your wits about you quite a lot of the time.

Any other questions just ask

 

[oldmanofthehills]

All the above advise is sound. Ideally plan to get to Nash Passage at low tide and simply take the tide up. The extra hour of tide at Portishead gives considerable margin unless you insist on drifting up with 3kt wind. If you are too late you will never get to Portishead as the tides run 5kt against you, so motor on if needed. Nash passage is very sheltered except for the entrance and I have been in and out in F6 gusting F7 looking somewhat awed at sea pounding on the seaward sandbanks, though it might be unpleasant in some wind directions. More usefully the tides are weaker inside the grounds and to get from Swansea to the Nash at low tide its easier inside the grounds.

If you go for purist sailing in light weather however and the tide turns as you approach Cardiff, go into the lagoon and enjoy the delights of Mermaid Quay.