Vízügyi Közlemények, Az 1998. évi árvíz, 2003 (különszám)

I. kötet: Az 1998. évi árvíz - Váradi József: Bevezető

EDITOR S PREFACE Ever since her foundation 125 years ago in 1879, the editors of the journal Hydraulic Engineering have consistently devoted special care to publish detailed accounts of major floods, inundations by undrained runoff, of the course of events and analyses of the professional experiences gained. These articles and reports have always represented an invaluable source of information to those responsible for taking decision on the policies and methods of future improvement of the defences, on the application of more efficient organisation patterns and on the introduction of new materials, techniques and technologies of emergency measures. The hydro-meteorological situation and events leading to the national disaster in 1940, to the then record flood on the Danube in 1954 and 1965

, further to that on the River Tisza in 1970 had been described in special issues together with the lessons learned from these. With the intent of continuing this tradition the particulars of the four abnormal Hood waves will be presented, which had travelled down the River Tisza between November, 1998 and March, 1991. Contrary to widespread belief, large Hoods are relatively rare. During the 146 years long period from 1855 to 2001 no more than 23 floods have passed down the River Tisza and her tributaries, which could be classified important or abnormal in terms of some criteria and have set milestones in the evolution of the defences in the Tisza Valley. Major floods have always revived public interest in, and provided impetus for, flood control development. This was the case in the past centuries as well, when e.g. approval of, and the commencement of construction work on, the ambitious Tisza Valley Reclamation project was prompted by the floods of 1816, 1830 and 1845. The subsequent floods in 1855, 1867-68, 1881 and 1888, each of disastrous proportions, have re-emphasised the importance of continuing and completing the works. The 20

th century has brought no change in philosophy. The extension of flood control to the lands between the Tisza and Szamos rivers was triggered by the 1913 flood, while work on the defences along the flood plain sections in Borsod County were started after the/9.?2flood (and completed in 1937). This was the last constructional measure which has reduced substantially the area of the open flood plains along the Hungarian section of the River Tisza. The flood disaster on the Upstream-Tisza on New-Years eve in 1947-48 had direct consequences, in that it has justified the re-organisation of water management in Hungary including the nationalisation of the associations. In response to the experiences gained during the floods in 1964 and 1966 the engineering-technological level of emergency operations was improved materially. The 1970 flood in the Tisza Valley has resulted in the adoption of a new approach in the revision of the design flood levels. The Körös floods of 1974. 1980 and 1981 have made imperative the formulation and implementation of a new development strategy of the defences, viz. the use of emergency storage. The experiences gained during the four abnormal floods between 1998 and 2001 have been collected, arranged methodically and processed over the past two years. Compounded with these were the observations made during the extensive inundations caused by undrained runoff in 1999-2000 and the heavy local losses wrought on minor