Hidrológiai Közlöny, 2016 (96. évfolyam)
2016 / 3. szám - HISTORICAL SNAPSHOT - Ligetvári Ferenc: The power of irrigation
36 Hungarian Journal of Hydrology Vol. 96. No. 3. 2016. come of national economies is not sufficient for the necessary developments. Realizing this economic reason people who are expecting bleak future are leaving their homeland (mother country) in the hope of a better living. With previous investments an almost fair method of water distribution was established where they are heading for. The knowledge of resources in itself is not enough. Efforts must be made for the formulation and working out of optimal developments. The role of responsible decision-makers requires great caution in the event of all changes. Perhaps it is true also for them what true is for an engineer following a resolution: Knowledge, Ingenuity (seeing behind the scenes), and Integrity. HUNGARIAN POLICY-MAKERS’ VISION IN THE 1960s It is well-known internationally that Hungary has excellent climatic and soil conditions. All these enable its active participation in feeding the world. Besides production volume the production of quality goods is an equally important aim. The increase of crop yields is based on the coordination of production conditions and factors affecting yields. The most significant production conditions are: proper agricultural techniques, sufficient amount of organic and inorganic fertilizers, plant protection, optimal water supply, introduction of the production of intensive varieties etc. In order to increase production plant breeding, nutrients and water supply have major roles. When the production factors - aside from water — are in optimum, water becomes the key factor of yield increase and the application of irrigation necessarily occurs. The best production areas of the country are located in the valley of River Tisza. However, water scarcity occurs in these areas during the years (Fig. 3 and 4). This led to the discovery that elimination of water scarcity occurring during the growing period can happen by the construction of reservoirs. The capitalist form of economy between the World Wars I and II made also necessary the irrigation water supply of peasant smallholdings. For this purpose the building of Tiszalök Barrage had been started but its construction could be completed only after World War II in 1954. With its construction the water supply of the south-east region of the country surrounded by the three- branch Körös River has been solved through the East Main Canal and Berettyó River. Many people make critical statements and approach to the barrages with negative feelings. Although the low precipitation in the growing period and its extreme temporal distribution can be counteracted only with the use of mainly winter water collected in reservoirs. The following barrage built on River Tisza at Tiszalök, an other one, the Kisköre Barrage was implemented with the same aim. It is well known that 300 mm rain may fall in the growing period in the middle of the Great Plain, while up to 500 mm rain may fall in the Western part of the country. Owing to this the total water demand of plants can be supplied with the irrigation of 175 mm water in addition to the natural precipitation in areas affected by water scarcity. The various water supply indexes, so the water scarcity in the growing period or the quotient of the potential evaporation and the expected precipitation, the aridity values verify the construction of the new barrage. Figure 3. Average precipitation of the growing period Figure 4. Aridity map of Hungary Reasons for the implementation of the Kisköre Barrage and its irrigation systems Four-fifths of the Great Plain can be irrigated only from the River Tisza and its tributaries. The River Tisza is the main artery of the Tisza Valley river system. The extremely fluctuating natural discharge of River Tisza, the minimum flows occurring in months July - August and the water demand of the irrigations and fish ponds established until the end of 1965 demonstrate that irrigations cannot be developed further in the valley of River Tisza. Moreover, in years of drought the demand of the existing water uses cannot be satisfied. Water scarcity even increased during the last quarter of the last century because of the newer water uses realized in the neighbouring countries - in the territory of the then Soviet Union, Czechoslovakia and Romania. Therefore, in the central area of the Great Plain with the lowest precipitation, large-scale water supplementation establishments had to be constructed which increased the natural low summer discharge of River Tisza and satisfied the water demand being necessary for the further development of irrigation. That is why the Kisköre Barrage with the connecting reservoirs and irrigation systems were built. The fulfilment of the water management and agriculture development needs closely related to the economic development of Tisza Valley made the implementation of the Kisköre Barrage and its irrigation systems justified and necessary. (Fig. 5)