Problem:
Ocean debris is becoming a real issue on the server. Non-passable blocks are cluttering up waterways and making it nearly impossible to navigate ships through certain areas. Sometimes it's intentional griefing, other times it's just sunken/abandoned ships or crafts that were released while still floating and never despawned. Either way, it's making ocean travel a pain.

Solution:
Add a new craft type specifically designed to clear ocean debris, basically a bulldozer for water. This craft would work similarly to a harvester, but instead of breaking crops, it breaks non-piloted blocks in its path as it moves through the water. It could be used to clear shipping lanes, remove abandoned structures, and generally clean up the oceans (and save the turtles).

Of course like anything, the craft can have limitations like low speed, no weapons, etc.