But a pontoon such as Austin's requiring side access would also need to keep level, so was the water capacity for flooding entirely in the bottom section? If so, then that section would presumably need to be deeper than in a floating drydock with 2 sides, and that would work against the available draught for getting a ship on or off (unless it was in a deep hole!!).
Answers on 2 sides (or maybe 1) please .....
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