The Firth is well known for the strength of its tides, being among some of the fastest in the world, a speed of 16 knots (30 km/h) being reported close west of Pentland Skerries. The force of the tides gives rise to overfalls and tidal races which can occur at different stages of the tide. Some of the principal tidal races are:
‘The Merry Men of Mey’. Forms off St John’s point in the west-going stream and extends as the tide increases NNW across the firth to Tor Ness. The worst part is over a sand wave field about 3½ miles (5.6 km) west of Stroma. The waves formed by this race form a natural breakwater with relatively calm water to the east of it, particularly noticeable when a westerly swell is running. Tides in this area can exceed 10 kts (18.5 km/h).
‘The Swelkie’. The race at the north end of Stroma, off Swelkie Point is known as ‘The Swelkie’. It extends from the point in an easterly or westerly direction depending on the tide and can be particularly violent. The whirlpool of the same name was, according to a Viking legend, caused by a sea-witch turning the mill wheels which ground the salt to keep the seas salty. The name derives from an Old Norse term, Svalga meaning "the Swallower".
The ‘Duncansby Race’ forms off Ness of Duncansby at the start of the SE-going tidal stream (flood). Initially extending ENE but wheeling gradually anti-clockwise until it extends about 1 ml. (1.6 km) NW some 2½ hrs later at which point it is known as ‘The Boars of Duncansby’. During the time of the SE stream there is additional turbulence off Duncansby Head, particularly to the East. The race temporarily ceases at the turn of the tide before forming in an ENE direction in the NW-going tidal stream (Ebb) before ceasing again at the next turn of the tide. The race is particularly violent and dangerous when the tidal stream is opposed by gales in the opposite direction. During the east-going stream a race forms off Ness of Huna. This race can be particularly violent in an easterly or southeasterly gale.
The ‘Liddel Eddy’ forms between South Ronaldsay and Muckle Skerry in the East-going stream (flood). A race also forms for part of the time off Old Head at the SE part of South Ronaldsay
I've stopped drinking water .... I have seen what it does to the bottom of our boat!
"The only time you have too much fuel is when you're on fire."
Thanks for that info Alf, I can see why the Cal Canal is so popular
MoBos are not as bad as a yacht with the mast down, but at displacement speed they are bloody uncomfortable in those conditions. The Colvic is a round bilge design & thus more susceptible to rolling than semi-displacement or planing craft with sharp chines.
For the top of Scotland I'd be inclined to hop between the islands where there are a few anchorages to wait for slack water. However the races up there cover several miles & require careful planning for a safe passage as mainland refuges are some distance apart. It is awe inspiring to stand on Duncansby Head or John o'Groats & watch & listen to the races roar from a mile or two away.
Maybe this old tub would be better suited to the journey
I just watched Tim Spall going round some headland near Peterhead. A twenty six foot, pretty, 6 knot Colvic does not seem the place to be on such seas. And they were nearly calm
Maybe the West coast is milder.
The S/D Sealion would be a better sea-going boat than Timmy-boy's - but you said you didn't want to take on a project? Have you seen all that wood?
They appeared quite concerned with what they may encounter around the top end and the NW coast and quite relieved when they didn't get a belting.
May 3, 2016
May 3, 2016