EN
Building roads and accompanying facilities in river valleys lead to partition and limitation of wild animals’ nesting sites. They also obstruct migration of certain spieces and organisms moving wit water. The task of water structures is to maintain damming as well as bed gradient, protect river bed against erosion and transport river sediment by dam section. This article analyses working conditions of overbuilt pipelines of culverts. Maintenance of road constructions, simplicity of execution, big repeatability of solution on utilization allowing the use of semi-fi nished elements are advantages. These conditions were examined with the aim to evaluate the degree of discharge limitation of the object by the passages for animals and sediment settled on the culvert’s bed line. Analysis of infl uence of building passages for animals in pipe culverts as well as amassed brash providing water organisms with maintenance of migration is discussed in the article. Presented analyses include study on infl uence of changes introduced in section of traverse pipeline on capacity of the object.