Not really, the draught of those catamarans is so small that they can safely navigate on most of the flooded plains that constitute the "River" De La Plata. Notice for instance that the colonia ferries never go that far southeast to then north. They go pretty much straight over the less than 5 meters zone. I remember joking with Buquebus crew that these ships can't easily sink, but rather soothly run aground and have to wait for hours for a rescue boat. I think it never happened and the only Buquebus accident was a small fire. The canals are for the truly ocean-going cargo ships and they go all the way up to Rosario (much like the tract between New Orleans and Baton Rouge, the biggest/most active port in America)