It might be a cool idea to program this map like pl_snowplow, in that the BLU tugboat would have to move through the locks of the canal, or in other words, move "up" the fishladder, and at each canal lock there'd be a trap that BLU would have to capture the point for so that the trap wouldnt damage their tugboat. BLU would win by getting the tugboat past all the traps, and the tugboat would sail through the final lock into the open sea, and RED would win by damaging the tugboat to the point where it explodes and sinks.

Basically, pl_snowplow with tugboats.

NOTE: just realized mid-way through this post that this map is payload RACE, not normal payload. So in that case, make a modified map whith just the BLU tugboat and nautical themed-traps (dropping anchor, collapsing dock, etc.) to make this a normal payload map.

One more thing-I just had a cool idea! Going on with the nautical themed traps, it woulld be awesome if the tugboat model had damage corresponding to which traps hit it-for example, the dropping anchor trap (similar to the falling car trap in pl_snowplow) would leave an anchor-shaped hole in the tugboat's superstructure if the anchor hits the boat and then comes back up, or, if the trap is a one-time damage hit, the actual anchor becomes lodged in the ship! And if each trap only hits and damages the ship once (in that case, make 5 or so traps total) then with the collapsing pier/bridgetrap, actual pieces of it/wood planks would be on the tugboat model as well!

NOTE: This was originally a comment, but the length was too long for the Steam comment requirements, so i'm posting it here.