It's nice of the community to build infrastructure for the merfolk. I bet they don't like stepping in seaweed any better than we do unless it's kept trimmed, but any time I try to mow the riverbed, my lawnmower dies and the park rangers get cross with me.
Do you think freshwater merfolk have some sort of echolocation like the pink river dolphins in the Amazon? So they can see through the silt? Apparently normal humans can do it so why not merfolk?