Khersan 3 Dam, one of the major water resources development projects in Iran, faces several challenges in the field of environmental impact assessment (EIA) and respect for the rights of local communities. This article aims to examine these challenges and provide solutions to improve the EIA process and protect local rights, by conducting a detailed analysis of this issue. Using qualitative methods, including library studies, document review, and content analysis of relevant laws and regulations, this study identifies and examines the environmental impacts of the construction of Khersan 3 Dam. The findings show that the project has caused destruction of natural habitats, pollution of water resources, changes in groundwater flow, and harm to local communities. In addition, weaknesses in the EIA process and insufficient participation of local communities are among the main challenges of this project. Emphasizing the importance of sustainable development, the article offers suggestions for improving the EIA process, increasing local community participation, and strengthening environmental monitoring to help reduce negative impacts and ensure long-term benefits for local communities and the environment.