Channel maintenance dredging

Channel maintenance dredging is the repeat removal of sediment that accumulates in a navigation channel after the original capital dredging, restoring the authorized depth. It targets shoaling from littoral drift, fluvial sediment, and tidal infill, and is scheduled by survey against the channel’s design depth and an allowed advance-maintenance over-depth. A trailing suction hopper dredger is the common tool for fine maintenance material because it works under traffic without anchoring; grab and water-injection dredging suit confined or thin-layer deposits. Volumes are tracked against pre-dredge and post-dredge hydrographic surveys to IHO S-44 order, and removed material is taken to a licensed disposal site or reused.