This study examines the role of environmental impact assessment in road construction planning and designing process to improve the traffic safety and diminish the fragmentation impact on wildlife habitats caused by road network. Qualified EIA of technical projects should provide sufficient amount of data and positive motivation for decision-makers to include environmentally friendly solutions in the early stages of road construction planning. The important result of EIA is the list of definite measures to introduce new or respect existing wildlife passages. In this study we have examined the traditions in road building industry in Latvia, when roads are constructed without special infrastructure for wildlife passages, as well as implementation and efficiency of measures recommended within EIA. The real efficiency of environmental measures is appraised with results of monitoring, in our case - with reducing of collisions with animals and number of animals and species used wildlife passages. In our study animals monitoring has been carried out during 2 winters on sections of 2 roads with different importance (category). The results of this study give answer what role has EIA for fauna conservation, how effective are recommendations of EIA and how usable for wildlife passages are bridges in Latvia.