Hidrológiai Közlöny 1977 (57. évfolyam)

1. szám - Mátrai István: A magyar vízügyi nagylétesítmények és a Vízminőségszabályozási Mintaterületek Project

Hidrológiai Közlöny 1977. 1. sz. 15 The large water projects in Hungary and the Pilot Zones for Water Quality Management Project By I. MÁTRAI» In the second half of the XX-th century, as a consequence of social, economic advancement, increasing problems have been encountered in meeting the domestic-, industrial- and agricultural water demands, especially in areas with scarce supplies. Growing demands have been accompanied by increasing pollution of the recipients, endangering also the existing water resources. A growing need has become apparent for increasing per cent of the average annual flow volume, while 99 per cent of the critical August supplies originate from the neighbouring countries. Both the Danube and the Tisza River originate abroad and only cross the country (Fig. 1). The August streamflow of 85 per cent duration is 1700 and no more than 250 cu.m/sec on the Danube and the Tisza Rivers, respectively. On the other hand, two-thirds of the present water demand <3)Plonne d A o Fig. 1. Hungary (1) Danube-Tisza Canal, (2) Existing (3) Contemplated, (4) Weir, (5) Water power station, (6) Canal, (7) Industrial area, (8) Major diversions, (9) Bank filtered wells 1. ábra. Magyarország (1): Duna-Tisza-csatorna; (2): Meglevő; (3): Tervezett; (4): Duzzasztómű; (5): Vízerőtelep; (6): Csatorna; (7): Ipari terület; (8) Nagyobb vízkivételek; (9): Parti szűrésű kutak the available supplies by the construction of great water resources projects for controlling runoff, such as dams, barrages, reservoirs and water transfers. Within the large water resources systems thus created additional care must be devoted to the conservation and control of the quality of the increased supply. Concerning water resources, the situation in Hungary is a very adverse one. The per capita water resources originating within the territory hardly exceed the 1000 cu

. m/year figure, which is one-fifth of the average for Kurope. The natural surface supply of 85 per cent duration is significant for the water balance and originates in 90 per cent from the Danube

—Dráva system and in 10 per cent from the Tisza River and her tributaries. 96 * Directór, Co-Manager UNDP/WHO Project Bureau, Budapest. appear in the less water abundant Tisza Valley, because of the extensive irrigation developments there. An added difficulty in the solution of the water management problems results from the nonuniform temporal distribution of the surface supplies, which in turn is due to the extreme water regime of the streams. Thanks to their Alpine character, the streamflow in the Danube and the Dráva rivers is fairly uniform, the ratio of the extreme flow rates ranging from 1 : 8 to 1 : 10, whereas on the Tisza River and her tributaries this ratio attains 1 : 50, or even 1 : 100, indicating their flashy regime. The safe yield from subsurface resources amounts to round one-sixth of the critical surface supplies. The following figures are illustrative of the water demands encountered in the critical August period of 1975: (2) Existing (4) River barrage A (5) Hydro power • (6) Canal g (7) Industrial areas WW (8) Major water intakes J* (9) Rlter wells