Vízügyi Közlemények, Kivonatok, 1965
Dégen Imre: Az 1965. évi dunai árvíz és árvízvédelmünk fejlődése
(34) 2.1 THE 1965 FLOODS IN AUSTRIA By Dipl. Ing., Dr. Techn. H. Zettl (Austria) (For the Hungarian text see pp. 103) Besides the Danube flood several other exceptional floods occurred in Austria, in 1965. A brief hydrological review is presented about their causes and progression in the paper. In this connection the events of special interest and influence on floods in Hungary are discussed in greater detail. Stage hydrographs for the period April to September, 1965 are presented in Fig. 2 for a few major watercourses in Austria, from which the development of flood waves can be traced and from which a good overall picture can be gained on the great number and duration of frequently widely divergent phenomena taking place over individual catchment areas. The floods which occurred in April over the eastern and southern parts of Austria are described in Chapter 1. Rains of great intensity fell on the 21st, 22nd and 27th April, and monthly precipitation over the northern part of Burgenland and the eastern part of Steiermark exceeded by as much as 400° 0 the normal average. Over the eastern slopes of the Alps the excess was 300 0 0, while over the remaining parts of Austria from 150 to 200 %. The thickness of the snow cover in the mountains around the 2000 m zone attained 2 to 3 metres, while around elevation 3000 m in some places even 5 m. The rainwater which fell on the 21st and 22nd April formed direct runoff and stages on the watercoui^es in the catchment areas of the Rába, Rábca and Lajta Rivers rose in many places above maxima on record. The first flood catastrophe in 1965 caused severe damages to streambeds, flood levees and extensive inundations. Discharges of the Danube, and over the reach of the Mura River downstream from Gro.z showed at the same time no extraordinary increase. Chapter 2 is concerned with floods in May —June. Repeated extensive rains occurred in May, with the number of rain}' days exceeding on the majority of raingages 15 and even 25. Precipitation over large parts of Austria surpassed 200 and even 300 % of the normal average. As a consequence further severe floods occurred in May. but these centered over the western parts of the country. Two flood waves passed in succession on the Salzach , the lower reaches of the Inn, as well as in the catchment of the Enns, Traun and Mura rivers, which raised stages in the Danube considerably. Adverse weather conditions continued in the first part of June also and were followed by a calmer period. Over the Austrian catchment of the Danube rainfalls of great extension and high intensity occurred at low temperatures between the 8th and 11th June. Western tributaries of the Danube responded with a very
