question

She died.

i think you mean the whole scene (also before she died). maybe the ocean can be interpretet as a symbol for fading life? see also the scene before, when the water goes back...

besides the fact of the symbolic use of the drying of the lake, it was/is common use here in holland to drain big lakes to create polders. this land is then used for crops or cattle, while the land is constantely being drained to stop it from filling up again. I think they used this in the movie also to point out the passing of time, we used to have a lot of big lakes, but quite a few of them are gone now...

In my view, when the father had to get a boat, the 'passage' was not ready yet, at least for the girl. With the passing of the years, the lake turns shallower. And, when she is very old, the lake is dry. Now it is the time for her to go. Beautiful film.

It means the time passing. Everything changes, sea recedes to field, the daughter grows old. But the only unchanged is her love and awaiting to the father.

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