 |
| Titel |
A Flash Flood Study on the Small Montaneous River Catchments in Western Romania |
| VerfasserIn |
Maria-Mihaela Győri, Ionel Haidu, Joël Humbert |
| Konferenz |
EGU General Assembly 2013
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250083820
|
|
|
|
|
|
| Zusammenfassung |
| The present study focuses on flash flood modeling on several mountaneous catchments
situated in Western Romania by the use of two methodologies, when rainfall and catchment
characteristics are known. Hence, the Soil Conservation Service (SCS) Method and the
Rational Method will be employed for the generation of the 1%, 2% and 10% historical flash
flood hydrographs on the basis of data spanning from 1989-2009. The SCS Method has been
applied on the three gauged catchments in the study area: Petris, Troas and Monorostia
making use of the existing interconnection between GIS and the rainfall-runoff models.
The DEM, soil data and land use preprocessing in GIS allowed a determination
of the hydrologic parameters needed for the rainfall-runoff model, with special
emphasis on determining the time of concentration, Lag time and the weighted
Curve Number according to Antecedent Moisture Conditions II, adapted for the
Romanian territory. HEC-HMS rainfall-runoff model (Hydrologic Engineering Center-
Hydrologic Modeling System) facilitates the historical 1%, 2% and 10% flash flood
hydrograph generation for the three afore mentioned watersheds. The model is calibrated
against measured streamflow data from the three existing gauging stations. The
results show a good match between the resulted hydrographs and the observed
hydrographs under the form of the Peak Weighted Error RMS values. The hydrographs
generated by surface runoff on the ungauged catchments in the area is based on
an automation of a workflow in GIS, built with ArcGIS Model Builder graphical
interface, as a large part of the functions needed were available as ArcGIS tools. The
several components of this model calculate: the runoff depth in mm, the runoff
coefficient, the travel time and finally the discharge module which is an application
of the rational method, allowing the discharge computation for every cell within
the catchment. The result consists of discharges for each isochrones that will be
subsequently interpolated in order to obtain the hydrograph of the historical flash
floods. The two methodologies employed offer the hydrologist the opportunity of
computing the historical hydrographs be it on a section of the river at choice, or
for every affluent within the small river basins studied, the graphical data being
easily accessed both in GIS and HEC-HMS. The peak discharge values of the main
rivers as well as those of their tributaries are of great importance in establishing the
hydrologic hazard under the form of floodplain maps that are inexistent for the studied
watersheds.
Key words: flash flood modeling, ungauged catchments, GIS, HEC-HMS rainfall-runoff
model.
Aknowledgements
This work was possible with the financial support of the Sectoral Operational
Programme for Human Resources Development 2007-2013, co-financed by the
European Social Fund, under the project number POSDRU/107/1.5/S/76841 with
the title "Modern Doctoral Studies: Internationalization and Interdisciplinarity". |
|
|
|
|
|
|