Newly-designed structures and landscaping elements are often used for flood protection.This article assesses the use of existing sunken lanes for retaining water in a landscape andthe sedimentation of washed-off soil. The article also describes ways how to preserve or, atleast minimally disrupt, existing biotopes and landscape segments. Geodetic data from onespecific sunken lane in South Moravia in the Czech Republic were transferred to a digitalterrain model; 9 models were subsequently generated, each with a different longitudinalsunken lane bed slope. Retention dams consisting of gabions were placed in them. Thenumber of dams, the volume of structures made of steel gabions, and the retention areavolume behind the dams were determined for each model specifically. It was determinedthat the number of dams, as well as their total volume, increased with the averagelongitudinal slope of the sunken lane bed. It was also discovered that the retention volumeremained almost the same, as it only very slightly decreases with an increasing longitudinalslope.
