A Simulation-Optimization System to Assess Dam Removal With a Focus on Environmental Degradations at Downstream

The present study proposes and evaluates an integrated framework to assess dam removal in which downstream river habitats and reservoir operation were simulated in three different statuses including conventional reservoir operation optimization, optimal release considering environmental aspects in the structure of the optimization model and natural flow. Fuzzy physical habitat simulation was used to assess physical habitats. Moreover, ANFIS based model was utilized to simulate thermal tension and dissolved oxygen tension at downstream habitats. Particle swarm optimization was applied in the optimization models. Results of the optimization models and habitat suitability in the natural flow were compared by applying different measurement indices including reliability index, vulnerability index, The Nash–Sutcliffe model efficiency coefficient (NSE) and root mean square error (RMSE). Based on the results in the case study, reliability of water supply might be reduced in the optimal release for environment and demand. Furthermore, optimal release for environment is not able to protect downstream aquatics habitats properly. Thus, if protecting downstream habitats is aimed, dam removal might be logic in the case study. The main limitation of the proposed method is high computational complexities.