Nonparametric design hydrograph in the gauged cross sections of the Vistula and Odra basin

The Archer method for construction of nonparametric hydrographs was regarded as the basic one for constructing design hydrographs in gauged cross sections. The hydrographs designed using this method belong to a group of non-formalized hydrology. Unlike the commonly used formalized methods, where a nonparametric hydrograph is strictly determined and defined, the hydrographs defined in this way are constructed on the assumption, that flow is the main determined parameter. On the other hand, the Archer method assumes that the basic parameter is time, which is determined for assigned standardized flow, called a flow percentile. Hydrographs constructed using this method are the basis for constructing parametric design hydrographs used for engineering computations. The Archer method is relatively new and should be verified for various regions. Presented manuscript compares the results obtained using this method in the middle Odra and upper Vistula basins with the nonparametric method developed at the Cracow University of Technology, called the Cracow method. The obtained results show, that four highest registered flood waves are sufficient to construct a nonparametric design hydrograph, whereas semi-standardized volumes above descriptors W75 and W50 and the duration time of the descriptors are bigger than the volumes and duration times calculated by means of the Cracow method in the Vistula River basin, and approximate with regard to the values in the Odra River basin.