Rainfall-Runoff Simulation and Modelling Using HEC-HMS and HEC-RAS Models: Case Studies from Nepal and Sweden
(2018) In TVVR 18/5009 VVRM01 20181Division of Water Resources Engineering
- Abstract
- Floods are probably the most frequent, widespread and disastrous hazards of the world. Almost every year, Sweden and Nepal are affected by floods though their nature and impact differs due to complete different geographical and hydrological setting. This study aims to develop Hydrologic Engineering Centre’s Hydrologic Modelling System (HEC-HMS) and Hydrologic Engineering Centre’s River Analysis System (HEC-RAS) models for Kankai River basin of Nepal and Kävlinge river basin of Sweden to analyse the effects of rainfall on surface runoff and peak discharges of these rivers and ultimately produce flood inundation levels to assess the flood risks in both areas. Being a rainfed catchment, the flood discharges of Kankai River are highly affected... (More)
- Floods are probably the most frequent, widespread and disastrous hazards of the world. Almost every year, Sweden and Nepal are affected by floods though their nature and impact differs due to complete different geographical and hydrological setting. This study aims to develop Hydrologic Engineering Centre’s Hydrologic Modelling System (HEC-HMS) and Hydrologic Engineering Centre’s River Analysis System (HEC-RAS) models for Kankai River basin of Nepal and Kävlinge river basin of Sweden to analyse the effects of rainfall on surface runoff and peak discharges of these rivers and ultimately produce flood inundation levels to assess the flood risks in both areas. Being a rainfed catchment, the flood discharges of Kankai River are highly affected by the extreme rainfall events whereas Kävlinge River has a significant influence of ground water. Apart from some extreme events, HEC-HMS modelling using Soil Moisture Accounting (SMA) loss method, manage to simulate flood discharges of Kankai River more accurately than Kävlinge River. The flooding impact of Kävlinge River is significantly less as the catchment is small with defined flow route while the Kankai River being a large catchment with braided river form, inundates vast downstream flood plain region during high flood level. With numerous people living along the river and downstream plains, flood risk is predominately high in the Kankai River catchment. (Less)
- Popular Abstract
- Sufficient and reliable flood predictions and proper design of control and mitigation measures remain a major challenge everywhere in this world. To overcome this challenge requires a proper understanding of underlying hydrological and hydro-dynamic processes of river and the associated catchment characteristics. This paper aims for hydrological and hydraulic modelling of two catchments: Kävlinge river basin in Sweden and Kankai river basin in Nepal and a comparative study of these models which are in completely different climatic zones and topographic locations.
Kävlinge river basin lies in temperate zone with precipitation in the form of snow and rainfall. The precipitation is distributed throughout the year with mostly snowfall... (More) - Sufficient and reliable flood predictions and proper design of control and mitigation measures remain a major challenge everywhere in this world. To overcome this challenge requires a proper understanding of underlying hydrological and hydro-dynamic processes of river and the associated catchment characteristics. This paper aims for hydrological and hydraulic modelling of two catchments: Kävlinge river basin in Sweden and Kankai river basin in Nepal and a comparative study of these models which are in completely different climatic zones and topographic locations.
Kävlinge river basin lies in temperate zone with precipitation in the form of snow and rainfall. The precipitation is distributed throughout the year with mostly snowfall between December to March and rain for rest of the year. The basin area is mostly flat with till as dominant soil type. Whereas, Kankai river basin lies partly in tropical and temperate zone. The precipitation occurs only in the form of rain and is concentrated in summer months between July to August. Unlike Kävlinge basin, its topography is highly varying with steep upper part and flat lower part with high percentage of clay throughout the basin.
The hydrological model using HEC-HMS was carried out to study the effect of rainfall on surface runoff and peak discharges and flood inundation maps produced through HEC-RAS were used to study the flood extent and its characteristics. The rainfall runoff modelling (HEC-HMS) was found to be more suitable for Kankai River basin than Kävlinge as Kankai is a rainfed river while Kävlinge river has more influence of groundwater. Furthermore, it was observed that the hydrological models of both basins were controlled by land use type more than other factors (climatic, geographic). Therefore, the result of sensitivity analysis of different parameters used in HEC-HMS depicted that both models were influenced by groundwater parameters. According to the hydraulic modelling (HEC-RAS), the flooding impact of Kävlinge River is significantly less as the catchment is small with defined flow route while the Kankai River being a large catchment with braided river form, inundates vast downstream flood plain region during high flood level. The area inundated by Kankai river was found to be 13 times bigger than that of Kävlinge basin during 100-year flood. With numerous people living along the river and downstream plains, flood risk is predominantly high in the Kankai River catchment. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/8956602
- author
- Khadka, Jeevika LU and Bhaukajee, Jagritee LU
- supervisor
- organization
- alternative title
- Hydrologic and Hydraulic Model Development for Flood Inundation Mapping of Kävlinge and Kankai River Basin
- course
- VVRM01 20181
- year
- 2018
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- HEC-HMS, HEC-RAS, Kankai, Kävlinge, Rainfall Runoff, Flood Inundation, Modelling
- publication/series
- TVVR 18/5009
- report number
- 18/5009
- ISSN
- 1101-9824
- language
- English
- additional info
- Examiner: Kenneth M. Persson
- id
- 8956602
- date added to LUP
- 2018-08-24 09:27:13
- date last changed
- 2018-08-24 11:05:46
@misc{8956602,
abstract = {{Floods are probably the most frequent, widespread and disastrous hazards of the world. Almost every year, Sweden and Nepal are affected by floods though their nature and impact differs due to complete different geographical and hydrological setting. This study aims to develop Hydrologic Engineering Centre’s Hydrologic Modelling System (HEC-HMS) and Hydrologic Engineering Centre’s River Analysis System (HEC-RAS) models for Kankai River basin of Nepal and Kävlinge river basin of Sweden to analyse the effects of rainfall on surface runoff and peak discharges of these rivers and ultimately produce flood inundation levels to assess the flood risks in both areas. Being a rainfed catchment, the flood discharges of Kankai River are highly affected by the extreme rainfall events whereas Kävlinge River has a significant influence of ground water. Apart from some extreme events, HEC-HMS modelling using Soil Moisture Accounting (SMA) loss method, manage to simulate flood discharges of Kankai River more accurately than Kävlinge River. The flooding impact of Kävlinge River is significantly less as the catchment is small with defined flow route while the Kankai River being a large catchment with braided river form, inundates vast downstream flood plain region during high flood level. With numerous people living along the river and downstream plains, flood risk is predominately high in the Kankai River catchment.}},
author = {{Khadka, Jeevika and Bhaukajee, Jagritee}},
issn = {{1101-9824}},
language = {{eng}},
note = {{Student Paper}},
series = {{TVVR 18/5009}},
title = {{Rainfall-Runoff Simulation and Modelling Using HEC-HMS and HEC-RAS Models: Case Studies from Nepal and Sweden}},
year = {{2018}},
}