| Author | Kyaw, Kay Khaing |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Water Engineering and Management |
| Publisher | Asian Institute of Technology |
| Abstract | This study presents developing flood hazard mapping for lower Ayeyarwaddy delta and also taking into account for land cover change impacts. HEC-RAS model is choosen for flood inundation mapping and thereby to produce flood hazard maps corresponds to 10,20, 50 and 100 years return period flooding events. Based on these flood map, land cover change scenarios are proposed to reduce flood inundated areas. The requisite peak discharge data set for the inundation model is produced from the rainfall-runoff modeling utilizing HEC-HMS.
In the rainfall-runoff model, terrain processing of delineating watershed and basin characteristics are processed in HEC-GeoHMS. When developing HMS model, basin model, metrological model and control specifications are required. Observed rainfall from hydro-metrological stations and Aphrodite global data are used as time series data input to the HEC-HMS. Calibration and validation are done for 10 and 5 years each. By using Gumbel’s distribution, rainfall depth duration frequency data are analyzed and input to frequency storm method of HEC-HMS. The runoff for different return periods are simulated and are used as flow data in the hydraulic modeling. According to the trend of inflow data from sub-catchments, sub-basin no.5 is highly contributed and other sub-basin no.1, 2 and 4 are followed. To reduce flood peaks, curve number changes in sub-basin is effective so that scenarios are proposed by changing curve number, time of concentration and storage coefficient in sub-basins.
In Hydraulic model HEC-RAS, calibration and validation are done with the same periods of HECHMS model. After calibration and validation, small and big flood periods are taken to run the model and produce flood maps. By using flow data for different return periods, flood maps for different return periods are produced. Flood hazard maps of different return periods are used as base line and there is a decrease of flood inundated areas under each land cover change scenarios. As a result, Danuphyu is the most flood vulnerable areas and these areas can be reduced by proposed land cover change scenarios. These maps can be used to prevent or mitigate flood disaster for the local community. |
| Year | 2018 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Duc Hoang Nguyen ; |
| Examination Committee(s) | Shrestha, Sangam;Virdis, Salvatore G.P.;Hoa Xuan Pham ; |
| Scholarship Donor(s) | Deutscher Akademischer Austausch Dienst (DAAD) Germany – AIT Fellowship ; |