Question on commuting in Region play by water

[RubinoCE 1]

I have a question.  I am starting a 16 city region.  I see the the cities are group in 4 each with 1 Great  works each.  The regional highway is not connected between groups the groups of 4.  My question.....Will worker/shoppers/tourists/students commute between the groups of 4 via the water connection, or will they only commute within their respective groups defined by their common regional highway?  Thanks for your help.

[thefallzversion 0]

This is something I've wondered as well.  Anyone know?

[perafilozof 143]

Since they will commute by train between two cities from two separate clusters connected by regional train tracks, they will also use the ferry to commute to distant cities from other clusters. 

[bokrif 18]

Yep, I think this kind of partitioning of large regions are about resource sharing, as you can't export more than your current amount of water/electricity/else then this amount divided by the number of possible import cities. Dumb game rule..