Awesome! I lived on a houseboat for a couple of years (still miss it). I was always happy when boats started dredging when I was home. Mesmerizing. All the stuff they got out of the canals (mainly bicycles). This project 'Below the surface' is about what they have found because of the building of the North-South metro line (which, btw, I'm going to boycot. Shame on Amsterdam, but that's a different story).
Nice website where you can create your own display with the finds. Be an artist, unleash your creative self and try it out. And of course there's a book which I'm not going to buy (see remark in the first alinea, although my curious self wants to, but I will stay strong).
Below a documentary 'Amstel, mirror of the city' by AT5, yes, with english subtitles added.
Amstel, Spiegel van de Stad from AT5 on Vimeo.