The design called for water to remain year round and for the entire bottom to be filled with the stones. I think the latter has been discussed here already.
One of the earlier materials suggested the natural ice could be used for skating (of course this is aspirational as even natural ice requires a lot of maintenance for skating).
Year round water with stone bottom vs an empty pond with concrete floor for half the year is a pretty big difference! Considering the incredible level of detail that goes into designing this thing, it's like building a palace but the front door is from home depot and the front lawn is dirt.
A huge consideration for the designers is how the park will be used. How will people use the empty concrete pond? graffiti, skateboarding. a truly interesting experiment
the attached are from Waterfront TO.
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