Vízügyi Közlemények, Kivonatok, 1965
Dégen Imre: Az 1965. évi dunai árvíz és árvízvédelmünk fejlődése
(47) 3.7 FLOOD CONTROL OPERATIONS ALONG THE TRIBUTARIES IN TRANSDANUVIA By L. Najmányi, Civ. Engr. (For Hungarian text see pp. 274) Floods along the tributaries discharging into the Danube over the Moson Danube Arm at river station 1749 km are closely interrelated with the Danube high water. These tributaries are the Marcal, Lower Rába. Rábca and Lajta Rivers enclosed by levees, and the Upper Rába with its tributaries and the Répce Rivers along which no levees have been built so far. The aggregate length of the levees is 391 km. Round one-half of the about 18.000 sq.km large catchment lies on the territory of Austria (Fig. 1). Tn connection with the floods in Austria it has been stated in Paper 3.1 that rainfalls substantially in excess of the average occurred over the entire catchment area (Fig. 2) and as a consequence thereof high waters surpassing maxima on record occurred almost simultaneously on each of the watercourses crossing the Hungarian —Austrian borderline. Sudden inundations of long duration resulted on Hungarian territory along the unleveed sections of these watercourses but grave situations developed over the leveed stretches as well. These discharges formed eventually a significant contribution to the Danube high water. The succession of flood waves is clearly represented by the stage hydrograph of the Rába River (Fig. 3). Floods appeared in three cycles in the Rába Basin. In the first cycle, from April 22 to the middle of May three, in the second, from the end of May to the second half of June five, and in the third cycle, from the end of June to the middle of July two flood waves passed. The paper is concerned mainly with the first cycle. Flood events over the unleveed reaches are described in Chapter 1, detailing floods of the Gyöngyös and Sorok Creeks , both tributaries of the Rába, which inundated the southern parts of the town Kőszeg (Fig. 4) and the central parts of Szombathely town (Figs. 5 and 6), together with several villages. An account is given on the flood of the Répce River of which the levees of the flood relief canal crevassed (Figs. 7, 8) and several villages were inundated, on the flood of the Pinka Creek inundating also a number of villages. Stages in the Rába were raised by bridge backwater so that several villages and parts of Sárvár were inundated (Fig. .9). Protection against the end-April flood over the unleveed stretches of small watercourses was practically impossible. Flood events over the leveed reaches are described in Chapter 2. At several points along these stretches, namely in the flood relief canal o£ the Répce River, the Rába and Marcal Rivers, the Hanság Main Canal and the Lajta River, stages were flush and above the levee crest and overtopping
