As shown in the attached screenshot, currently, tidal rivers do not have wide estuaries when they meet with the sea. It would, I think, enhance both appearance and gameplay challenges if tidal rivers such as that shown could be generated with estuaries (i.e. - they get wider when they get near the sea) to match their real life counterparts.
Well, an estuary is more or less the end of a river, asuming all rivers in game end up in the sea, so a possible solution would be to create a end tile for rivers that represents the estuary.
I'm not quite sure how that would work to make estuaries wider than they are now...?
more of a problem for experimental, where the tile size can be set to 250 m. In standard the tile size is already 1 km, that should be enough for estuaries.
What counts is the relative size of the estuary compared to the width of the river itself. The shape of the river mouths is currently incorrect.
The river gets wider: It is a full tile plus two border tiles at the lowest hight level.
The estuaries don't seem to widen enough in proportion to the width of the pre-estuary tidal river, though, as in the picture.
I can't help but notice that there aren't actually any river tiles in that screenshot, only sea.
Tidal rivers are generated in game by lowering a channel of land to sea level on map generation.
That is the widening ...
Yes, but they'd widen
further just before they reached the sea.