Valentine322 said:

If they're standing in the middle of the river, they're about to get caught in the torrent, aren't they.
Man, this arc hasn't been nice to the girls at all.

Good guess, that's exactly what happened. Poor girls!

Yet again !

For a split second I thought it'd be cool to see Yuugi surfing atop this wave while holding the rest of the gang under her arms and on shoulders, but oh well!

I'm so amused that one of the earlier arcs had both Cirno and Mokou protecting themselves and their friends from a full-on avalanche (each in her own way), but in this one the wall of H2O just keeps winning.