Generally dams are considered as an integral part of the water source management system, which is effective in the regulating surface flows especially in areas with no uniform spatial distribution of rainfall and temporal. Considering the worldwide, developing trend for dam construction, especially in Iran, the necessity of reviewing the environmental impacts of dam construction becomes apparent. The main purpose of this paper is assessment of cultural and environmental impacts of dam on under irrigation and rural drainage network development. The method of research was qualitative and data were collected by interview, observation and transect base on theoretical protocol. Research population consist of council members in villages that covered by the dam irrigation and drainage network (N=48) that were chosen as the census. In order to analysis data were used mind maps and content analysis techniques. Results of content analysis showed that generally dam's cultural impacts are summarized in 6 general categories: cultural exchange, awareness, tourism, entertainment places revival, culture urbanization, destruction of social-cultural attachments. As well as the content analysis of research population, environmental impacts of dam include 4 types: 1-climate change, 2- entry of new species of birds to the region, 3-degraded landscapes and 4- green area.