Crossing the Sunk Sand - a 'new' route?

[tillergirl]

Question for forumites here please

I spent a while yesterday crossing the Sunk Sand in the vicinity of the Barrow No 6. I have a fair bit of work to do to reduce the data to Chart Datum and all that but my preliminary calculations show that there is a flat bit 0.7nm NE of the old beacon from the Barrow No 6 on a track of approx 115/295 degrees true. Unfortunately there is no easy transit, for example between the Barrow No 6 and the Black Deep No 7. After a number of runs in the best place, I did also try a transit of lining up the western line of the Gunfleet Wind Farm (as per Christo2024's suggestion) and eeekk 'that were shallow'! In fact, there wasn't enough water but then that is half a mile further to the NE and really attempting to cross the Middle Sunk which is a bit daft. (Curiously the Windfarm lines are really difficult to see when lined up and in the sun!)

However there is this flat bit, about a tenth of a mile wide on a 115/295 track beginning or ending on the Barrow No 6 (which is in approx 18 metres of water at CD), well clear of the SW Sunk Beacon wreckage with about 1.4m least water at CD.

That seems to suggest that this is a settled weather 'half tide' crossing for most.

It will take a little while to crunch the data and draw up a chartlet (annoying SWMBO in t'process - 'Are you on that computer again?'). Question is chaps and chapesses, is this worth the effort? Or is this a bit too restrictive? Views please?

Mind you I'll probably do it anyway........

 

[Phoenix of Hamble]

Definitely worth the effort.... a well documented half tide Sunk Sand crossing is certainly valuable to me!

 

[Athene V30]

Roger

Your efforts are always appreciated! So far this year I have managed to avoid crossing the Sunk Sand.

BTW coming back from Gravelines into Harwich I went 'outside' as it was better for the tide but was surprised to find that Long Sand sticks out a LOT further to NE than the chart (& CP) would suggest. In an area where there should have been about 4 or 5 m the depth was under 2.5 for quite a time so I turned 90 right and headed 060 until I had a bit of spare water under the keel before resuming.

 

[FullCircle]

Roger, that has been my 'normal' crossing point for a number of years.

However, when we went to Ramsgate week a couple of years ago, we had around F6 but still flattish, and took a southerly line from Barrow 6 about 300m until it shallows steeply then about 090/270 until about 2/3rds of way across charted sand, then dogleg south on a transit through the middle of Fishermans. We were seeing 2.1m at just after mid tide (can't remember neaps or springs dammit).

When we returned up the same track after a week of gales, that track was a visible bank of sand just past the dogleg on the Barrow Deep side of the bank. We edged North and found a new saddle (probably a result of the gales too) quite a long way north where the bank usually shallows. Around 1.8m. Much more messing around, and I was going to backtrack out and go the long way round!
We knew it was true, as I still had the GPS track loaded on screen from the previous week.

While I was typoing this I was looking at my wall at the Thames Estuary chart of April 1992 which sort of shows a channel through there. Looks like I used that for a Ramsgate to Burnham race at some point as that approx track is still on the chart.

 

[tillergirl]

Thanks chaps. I'll get cracking then.

FC - interesting. Don't suppose you have any coordinates? I rather fear that this spot is very liable to change. 1932 you could walk there!

 

[FullCircle]

Sorry Roger, I can barely remember what I had for breakfast.
We don't do any bold lines on the charts between Barrow and Black Deep, just sniff.....
We tend to creep that passage at 2.5kts or so until reassuring depth gradients start to dawn on the instrument.
As we are all aware, you can't take anything for granted in that area, which is why its so fascinating.