Vízügyi Közlemények, 2004 (86. évfolyam)

1-2. füzet - Tóth Sándor-Ijjas István: Árvízkezelés - európai trendek, hazai kihívások

128 Tóth Sándor-Ijjas Ist\>án both in the catchment of the River Tisza and in the hilly catchments of the Hungarian "Dunántúl", the area on the right side of the Danube. The regularly inundated flood corridors of our rivers had been reduced to 10.1% of the flood plain of the 1000 year flood (including the area of flood-islands), while that of the 100 year flood sunk to l/8th of the floodplain. The extent of the ecological floodplain of the rivers, which are to sustain a healthy aquatic ecosystem by more-orless regular inundation, that is the area that should be inundated for ecological purposes could be essentially less than the presently recorded protected floodplain. The area that shall be considered for this purpose is likely not more than the one that is annually inundated for at least 5-10 days. The determination of this area should be the task of scientific research. On the other hand the emergency reservoirs of the Tisza River Valley, which are included in the "Vásárhelyi Plan Update, the VTT", the recent flood control programme of Hungary, will potentially provide regular inundation for an area, which is one and half times larger than the presently inundated area. The VTT would best serve the requirements of the WFD and the European regulations when the options of regular inundation, as included in the VTT, will be realised. Regular inundations to be made for landscape management purposes can be implemented by using the flood flows of the river and this would best serve the interests of nature conservation and those of all stakeholders. In the case of floodplains within the levees, forming the flood channel, one must not always consider the flood conveyance capacity as the first priority. Considering the fact that the most valuable remnants of the natural habitats are found in this floodplain and also considering the obligatory compliance with the requirements of the WFD one may consider the complete clearing of the flood channel only on such cases when it can be justified and verified that there are no other ecologically more favourable means of flood conveyance. The inventories of small and open flood basins and uninhabited areas should be updated. The measures relating to these areas shall be such, after knowing the results of appropriate investigations, that supports the conversion of these area into parts of the green corridors, whenever possible, with the opening of the dikes. Regarding the analysis and management of flood risk the preparation of the document "Guidelines for the analysis and mapping of flood risk" was the only stepforward in Hungary. The document was prepared in 2003. Further steps for the development of pilot plans and the preparation of detailed guidelines are still to be done. Public consultations and the involvement of the society in the decision making are, unfortunately, made frequently only after having all important professional issues settled at ministerial level. This practice could be rectified by the promotion of the method of "planning the future jointly" with the involvement of all stakeholders.