Beached?

A wander round the Royal Harbour yesterday raised a couple of questions. How do ships the size of these get through an entrance as sandy as this? Has it always been like this, or are we going through a particularly silty period? Shouldn't the dredger be working here? OK, presumably this is not a new phenomenon, at high tide there is obviously enough clearance or the Grand Turk, the Customs and Excise boat and these two little ships wouldn't manage it, and obviously the harbour management are aware of this. But to the casual observer (me) it seems a little curious that the beach is so big at low tide.






And then overcome by nerdiness, I looked up the ships registrations. Finding myself in the world of Vesseltracker, ShipSpotting, and the World Shipping Register I learnt that the Hoo Swift and Hoo Pipit were built by the Yorkshire Dry Dock Company in Hull in 1989, managed by Coastal Bulk Shipping Ltd, Rochester and are of 794 GWT (that's Gross Weight Tonnage - cargo and related equipment). Lordy, lordy, where will this thirst for knowledge take me next?