This sign talks about the illusion, in two languages, but I'm not sure if you'll be able to see it and can't figure out how to make it zoom in... (new Photobucket, just getting used to it).
The idea was that all the little bits of paper looked like a pool of water with a high level, but you could walk along a little bridge and then see "under" the water. It was pretty cool in person.
I can read the sign. Thanks.

It looks pretty cool, all right! I would have liked to see it. Some installation work can be pure rubbish but when they work they are sooo fantastic and stay with you. Years ago there was an installation in Pearse St train station, Dublin, which is a Victorian roof with high eaves, and an artist had hung hundreds of tiny birdhouses, all different colours with something shiny on them, and they very subtly glittered and shone in the morning sunlight. Made the horrible rush hour commute to work a lot more bearable!