Colin says: The bubous bow which was so obvious in the earlier photo of the dredger in now completely submerged and is creating a massive bow wave ahead of the vessel. Unlike the prow of a traditional ship - a bulbous bow creates a relatively small wash which makes it idea for dredgers which work in narrow channels. The reduced wash is not only appreciated by other users of the channel but also helps to reduce the rate at which silt is eroded from the sides of the channel in the first place.
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