What is Dredge up?
Dredge up definition and meaning on Dictionary terms:
Also called dredging machine. any of various powerful machines for dredging up or removing earth, as from the bottom of a river, by means of a scoop, a series of buckets, a suction pipe, or the like.
a barge on which such a machine is mounted.
a dragnet or other contrivance for gathering material or objects from the bottom of a river, bay, etc.
verb (used with object), dredged, dredg