In message , at 17:19:56 on Sat, 16
May 2009, John Rowland
remarked:
Maybe they wouldn't be allowed to have platforms below water.

They are below water, just like the Jubilee line station.

The Jubilee Line station looks like it's entirely below ex-water to me.

I can assure you that the top half of the escalators down to the booking
hall, and the canopies over the entrances, are above water!
--
Roland Perry