Abstract: The invention relates to a dredging method for dredging a navigation channel for guaranteeing a nautical depth of a navigation channel. The method comprises performing agitation for mobilizing sediment and displacing the mobilized sediment to a collector which is embedded in the bottom of the navigation channel, the collector being a trench in the navigation channel wherein the trench has, when not being filled with sediment, a bottom level positioned substantially deeper than the nautical depth of the navigation channel. The method also comprises, in a step different from said performing agitation dredging, after solidification of the sediment collected in the collector, removing the solidified sediment from the collector so that the collector again has a bottom level positioned substantially deeper than the nautical depth of the navigation channel.

Abstract: A handheld profiling system for obtaining information regarding a mud, sediment, sand or soil is disclosed. The handheld profiling system comprises a sounding pole, a sensor array provided along the sounding pole, the sensor array being configured for providing a different output signal in air, water and sediment, and a measurement unit for determining a resistance on the sounding pole when intruding the sediment. A corresponding processing means and computer program product is also described.

Abstract: A computerized system for obtaining information regarding a waterway is described. The system comprises an input means for receiving accelerometer data from an accelerometer of a free fall object and a processing means being programmed for deriving, based on said data accelerometer data at least one of a density, a viscosity or a depth of a soil. The present invention also relates to a free fall impact object comprising such a computerized system, to a method for obtaining information regarding a waterway and to corresponding computer related products.