Determination of a waterway characteristic

A computerized system (200) for obtaining information regarding a waterway is described. The system (200) comprises an input means (210) for receiving accelerometer data from an accelerometer (110) of a free fall object (100) and a processing means (220) 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 (100) comprising such a computerized system (220), to a method for obtaining information regarding a waterway and to corresponding computer related products.