Determining the features of riverbeds is one of the principal tasks of measurement. via donau surveys flowing waters, ponds, lakes and the ocean at specific places, linearly and over entire surfaces. The riverbeds of flowing and standing waters are usually measured by standard single-beam echo sounders. via donau uses shallow water echo sounders for special tasks. Depending on the assignment, single and multi-beam sounders, sounding poles or other mechanical methods such as leadlines are used. The sounding ships are equipped with the latest instruments and are capable of combined position and depth measuring. In some cases, the data can be processed directly on site. A continuous data flow is assured for any post-processing that might become necessary. The results are available in analogue format as well as in profile, trackplots and isobath plans. The sidescan option of the multi-beam echo sounder also enables measurements in murky waters.