Got down there yesterday; day promised so much with nice early sunshine but it ended as a gloomy, misty day but without much wind so it was ok for the purpose. Strangely lumpy for 7kts of wind down to the Spitway; couldn't see the Gunfleet wind farm until I reached the Eagle when the two new larger turbines became visible - actually handy those on the return as they were pretty much the only thing visible on the way back when I rounded the East Barrow sands. Cross the Swin was pleasant though and vis was ok to pilot down to the Barrow No 6. Never saw the London Array though once, nor indeed nothing in the Black Deep, apart from one yacht coming north and turning up the Swin towards Harwich. Pretty lonely old day except for the chatter on London VTS. If that is any measure of the economy, things are looking up.
Enough of that: Findings!
Well have people have said, it's still there but has moved north-east a little. Or rather the old track recommended in 2012 cannot be used as there is encroachment of sand up from the direction of the old SW Sunk beacon. Just like Peter (Karouise) I touched - crump, crump. Sand - slightly soft, steep to, uneven and not very large - but very there. Strange because it wasn't very large and even though I was monitoring carefully I did not have sufficient warning to stop/avoid or do anything. One moment there was 2.5ft on the sounding, next crump! Even with very little swell, not actually going hard aground, twas not pleasant.
Anyway, Mystique's knoll is still there; this time with a couple of seals on it and I think it has retreated slightly to the NE but spread wider. I did start to try a circumnavigation but though I better use my time to go over the swatchway instead. The images shows the knoll at LW with 1.3 on the tide gauge at Margate (listen in to 69 for London VTS tide broadcasts at 15 mins to and 15 mins past the hour).
What we have is a passage with a controlling depth of 2m at chart datum (bear in mind that there is 1m+ height of tide at LW neaps but not as much at LW springs). I have worked up two new waypoints which are on the chart which can be downloaded as usual at http://www.crossingthethamesestuary.com/page6.html. The lines on the PDF are looking a little lumpy and I'll try and sort that to make it look a little better later on.
The yacht I mentioned coming north on my approach crossed to the NE of this charted swatchway - ie the other side of Mystique's knoll. I didn't have time to explore that (it takes two and a half hours of going backwards and forwards) but will try if we get another favourable wind/tide combination. Sorry not to be able to provide drying heights but that would require me to be down there at the top of the tide and of course from Mersea that means a plug down against the tide and a plug back against it making it a 12 hour stint rather than the 8 hour jaunt this is. Thanks to the launchman Dougie at West Mersea who hung on for me to get back so I could sleep ashore rather than on my mooring!