Vízügyi Közlemények, Kivonatok, 1965

Dégen Imre: Az 1965. évi dunai árvíz és árvízvédelmünk fejlődése

(38) Ruptures in the levees and consequences thereof are dealt with b, Chapter 3. The sequence of ruptures started at the climax of flood control operations on the 10th June. The following ruptures occurred (Fig. 3): 1. Novoszelo (river station 1360 km) on the 10th June, with 600 hectares inundated; 2. Kamariste (river station 1360 km) on the 16th June, with 17.400 hectares inundated; 3. Mladenovo (river station 1310 km) on the 23rd and 24th June, at two locations with 3000 hectares inundated; 4. Tshelarevo (river station 1284 km) on the 26th June, with 30.000 hectares inundated. Altogether 25.400 hectares were inundated. A detailed description is given of individual ruptures with special attention given to that at Kamariste, which was caused by erosion under the levee due to boil formation (Fig. 4). Water entering through the rupture was intercepted by an auxiliary dyke constructed on the edge of a high bank with heights varying from 1 to 3 m. Construction was carried out with great forces of labour and equipment; 40.000 men were employed per shift. Water was returned by blasting a cut in the main levee, which was then deepened by a suction dredge (Fig. 5). Experiences gained during flood control are summarized in Chapter 4. Fills placed on the riverside of the levee with a suction dredge proved very effective for strengthening the levee (Figs. 7 and 8). Cutoff sheet pile walls proved similarv successful (Fig. 9). The flood wave was one of the longest duration, caused greatest damages and involved highest costs for control. Losses to the national economy amounted to 88 thousand million Dinars (1965 currency value) of which 16 thousand millions were spent on control operations. Altogether 5 ruptures occurred and 7 return cuts were opened, the reconstruction of which necessitated 1 million cu.m earthwork. In 1965 1.8 million cu.m of earth were placed of which 1 million with hydraulic fill. Further works are envisaged to create uniform safety along the entire line of protection, the cost of which is estimated at 10.5 thousand million Dinars (1965 currency value). Favourable experiences gained during the improvement of levees at the time of the flood, as well as on realizing cuts and reconstruction of ruptures and cuts, further on final strengthening of levees with the use of suction dredges, is especially emphasized. A proper construction technology is a prerequisite for successful operation. Standard levee cross sections have been adopted for strengthening existing levees (Fig. 1G) where freeboard is 1.2 m, the width of the levee at the height of the highest stage is 16 m, and the slope on the protected side built by the hydraulic fill method is 1 : 7, in the case of cohesive soils 1 : 5