The use of NRCS synthetic unit hydrograph and Wackermann conceptual model in the simulation of a flood wave in an uncontrolled catchment

摘要

The paper presents the results of using two models: a conceptual model of Wackermann and a NRCS-UH synthetic unit hydrograph, for flow calculation in uncontrolled catchment of the Slonka, Poland. These models were chosen because of simplicity of models' parameters evaluation, what is important from engineering calculation point of view. Flows with the probability of exceed amounting to 0.5%, 1%, 2%, 5%, 10%, 20%, and 50% and for different levels of the catchment moisture were evaluated.The flood waves generated in the Wackermann model were characterized by a short duration (over 2 hours), shorter concentration time (about 1 hour), and by about 70% higher peak flow values than those generated using the NRCS-UH method. A common feature of both methodswere higher values of peak flows for the third level of the catchment moisture, as compared to the second level. It is also worth noticing that in both methods no flood wave was generated for the probabilities of 10, 20 and 50% and for the second levelof the catchment moisture. It was assumed that hydrographs made with use Wackermann model better describe flood wave in mountain river, which Slonka is.