Abstract. The natural rivers and their flood areas are among the most complex and diverse ecosystems in the world. Traditional structural solutions in river training works are focused on basic requirements as flood protection, littoral zone protection, river bed protection, providing the space for economic development. In this study a method of anticipated assessment of certain physical impact of designed river training works is presented, perceived as global effect of river bed artificialization. The method mainly serves to compare the various possible solutions of river training works, based on the „artificialization parameter” also named „global impact GI”. Key words: river training works, environmental cost