Investigation and simulation of flood inundation hazard in urban areas in Iran

Abstract

Extensive impervious area and the man-made streams are the characteristics of urban areas. In recent years, rapid urbanization has led to change of rural areas into urban areas, and urban runoff will increase as the result of spread and growth of impervious areas. Land use changes, increasing urbanization, unauthorized construction, inefficiency of sewage system and increased impervious surface in urban areas have significant impacts on inundation hazard. Therefore, to manage urban areas and prioritize regions to inundation elimination problems, the area most affected by inundation should be determined. In this study, the Storm Water Management Model (SWMM) is used to simulate the rainfall-runoff in the study area. The simulated runoff in the SWMM model is used as input to the HEC-RAS model and determines inundation hazard zones in 5, 25 and 50 return periods. Then, six factors such as distance from the main channel, slope, land use, drainage density, the main channel slope and elevation were selected to determine inundation hazard map using Analytic Hierarchy Process (AHP). The results showed that the combined model (SWMM and HEC-RAS) was suitable to analyze urban inundation and determine inundation hazard zones on urban areas. Simulated results can be used to develop urban inundation hazard forecasts. In addition, the result of inundation hazard map indicates that 8.2% of the case study is determined as a high hazard zone.

Designing effective educational storymaps for flood disaster mitigation in the Ciliwung River Basin: An empirical study

“…Zevenbergen et al further emphasize the need to traverse across spatial and temporal scales to address the challenges in urban flood management [2]. In a study conducted in Iran, Rostami Khalaj et al investigated and simulated flood inundation hazards in urban areas, highlighting the significance of understanding the dynamics of flood propagation in urban settings [3]. The adverse effects of flood disasters in urban areas are further exacerbated by hillside development, as noted by Teng and Chen.…”

The assessment of drainage performance in the residential area using SWMM

“…Water that has been accommodated in the detention pond will flow back to the drainage channel when the drainage channel is no longer filled with water. Detention ponds are usually shaped like ponds or artificial lakes formed according to the condition of the area [16].…”

Study of inundation and eco drainage system approach in Cicayur Kampong area

“…SWMM uses modeling with input parameters that have been recorded in field conditions [7][8][9][10][11]. Modeling using the SWMM can be built using five main environmental components: rainfall, temperature, and evaporation data; surface runoff components; subsurface groundwater components; pipe conveyance systems, channels, flow regulators, contaminant storage, and accumulation units [12][13][14][15]. Not all of these components need to be included in the analysis process, most only include rainfall, surface runoff, and the hydraulics of the conveyance system.…”