Dredging

I would like to be able to tidy up the edges of the map after removing the ground which seems unachievable with the excavators as they wont go far enough into the water to do it so maybe a dredging barge that works the same way as the excavators only in water.

Like a type of cargo dock that has a dredge. Which goes out to dig orders below water and returns to offload. Maybe only capable to -10.

I've really been wanting this! Please, devs!

Would be a good way to get sand and dirt as well.

This is needed.
My thoughts;
Size.wise a 2 module ship.
Speed and fuel usage as per mega excavator.
Needs a dedicated dock.
Tiers of dredging tech (sub -5, -10, -20)
Dredges up what has been dumped, + 20% volume with sludge as waste solids, plus 50% volume waste water
Volumes could be like the large dump truck (Capacity 180 solids = 150 solids, 30 sludge, 90 waste water)
Dock have 2 outputs, waste water and u-shape belt.