Developing Flood Economic Loss Evaluation Model in Residential and Commercial Sectors (Case Study: Darband and Golab Darreh Rivers)

Flood phenomenon is one of the catastrophic natural disasters which usually cause injuries and economic losses more than any weather phenomenon. Therefore, evaluating flood economic losses is important dramatically and it should be consider in socioeconomic development, spatial planning policies and flood control plans. Contrary to importance of this issue, available evaluating methods of flood economic losses are not comprehensive and there is not any consideration of environmental, economic and uncertainty approaches simultaneously. Comprehensive methods of flood economic losses evaluating help to decision makers for choosing best strategies of flood control in structural and non-structural plans. In this research flood losses scale and distribution are evaluated based on economic and environmental approaches. According to importance and requirement of developing a comprehensive master plan for evaluating flood economic losses especially in mega-cities, a flood economic losses evaluating model is developed in Darband and Golab Darreh Rivers and Maghsoud Beyk Channel using HEC-FDA model. The results showed most economic losses are occurred in 8 hazardous locations of residential sectors in Maghsoud Beyk Channel zone, also in this region total loss calculated is 12,220,237 dollars, and so the cost of flood control plan should be lower than this loss amount, in order to have economic justification. For the purpose of obtaining acceptable accuracy in evaluating flood economic losses, hydraulic and hydrological uncertainties have been calculated based on Monte-Carlo method.