|Water, silt, mud, spawning grounds, channels, life, death. Admiralty Chart, but scraped here.|
The Thames rises on the spring line of the Cotswolds, near Circencester in Gloucestershire, and runs 215km to the sea. The Admiralty (MoD now) chart above of the banks and channels at its mouth is ephemeral, like all of the underwater geography laid down by the river in its latest interglacial incarnation. With a 16,000 square kilometer catch-basin, it's not surprising that the Thames has a relatively small discharge of 65.8 cubic meters, compared with, say, the Escaut/Scheldt (120), Meuse/MaaΒ (350), much less the Rhine (2000) --not even that much more than the little Aa (10) or Medway (11)!
It carries enough before it, however, to water London, giving ships and their crews reason to thread their way through the sandbanks and silted shallows at the mouth of the river to the metropolis. The Gunfleet Sands probably do not their name from the weapons the weapons that ships had carried since perhaps the 1300s. They had already carried that name down from time immemorial by the days when the English fleets of the Anglo-Dutch Wars anchored there. Someone would have said something at a time when they were the focus of the Atlantic.