Motorways represent barrier effect for wild animals and they can disrupt their natural migration. To reduce this effect green bridges (overpasses) are built over the motorways. These overpasses increase cost of the motorway construction and do not have to bring the expected effect. Right location of green bridges is needed for sufficient functionality. There is also a need to ensure acceptable surface for wild animals and to reduce surrounding disturbances and to carefully evaluate financial cost. Migration potential is used to evaluate functionality of overpasses. Migration potential is calculated using functions corresponding to a gamma distribution function. From structural point of view concrete or wooden arches or double arches are being the most frequently used. It is not easy task to find acceptable compromise for economic and ecological aspect and to select correct materials and structural system. Our objective is to explore whether different type of structures and different materials used can have influence on functionality or price of the structure. To evaluate the total price of the overpass not only the building and preparation budget but also the maintenance budget must be taken into account.