LAND USE RELATED PAREAMETERS AS AN INPUT FOR THEESTIMATION OF FLOOD CHARACTERISTICS IN SMALL CATCHMENTS

References: 13th SGEM GeoConference on Water Resources. Forest, Marine And Ocean Ecosystems, www.sgem.org, SGEM2013 Conference Proceedings, ISBN 978-619-7105-02-5 / ISSN 1314-2704, June 16-22, 2013, 189 - 196 pp

ABSTRACT

The methodology for estimations of flood characteristics of small catchment is being developed at the Department of Irrigation, Drainage and Landscape Engineering. This methodology is supposed to be based on different catchment descriptors. It is considered that one descriptor will be expressed by land use related parameter. Several such parameters were selected for the detail analysis to get the data for the decision on the selection of the one most suitable for this purpose. In this paper, the model based analysis on the influence of land use related parameters on flood characteristics of small catchments is presented. The analysis was carried out using Gridded Surface Subsurface Hydrogogic Analysis (GSSHA) model. The catchment of Divišovský stream was used as the study area because it is an experimental site of the department which is well instrumented and thus there are calibration data available. The results show that interception parameters are not very suitable for given purpose. The main reason is that the model is very sensitive to a correct estimation of the parameter value in case of interception coefficient while in case of canopy storage capacity the influence on runoff characteristics is negligible. Other results were achieved by the analysis of Manning roughness coefficient which could be suitable for the methodology.

Keywords: land use, interception, overland flow, hydrologic modeling.