Egyszerű számítások és megjegyzések a magyarországi öntözővízzel kapcsolatban

In 2024, Hungary was asked to retain the 4 cubic kilometers of water that rivers carry out of the country more than they bring in. The first part of the article contains simple calculations to illustrate the magnitude of the technical task. It is important to understand that this means continuous withdrawal and also continuous transmission of water. The quality of the retained water is an important issue, including the possible presence of pathogens, drug residues and poisons, such as cyanide. Care must also be taken to prevent harmful side effects, such as the spread of malaria. It is often argued that a complete solution to the problem would be very expensive. In this regard, it is important to point out that the problem cannot be solved in a single year, because there is no such large construction capacity in the country, so only a fraction of the total cost would be charged to the state budget each year. It is also important to note that a complete solution to the problem will not only support agriculture, but also make life in the affected areas sustainable. A system must be built that covers the affected part of Hungary in the form of a large network or networks, but at the same time allows for the integration of available local options. Only elements that can be put into operation immediately after completion should be developed. It is also worth considering whether it is not necessary to fundamentally change the philosophy of irrigation and, through it, its regulation. It is also important to note that the circumstances – i.e. climate, water pollution, the location of settlements, the world market, including the domestic market, economic requirements, and harmful effects such as the spread of pathogens and the appearance of toxic substances – have fundamentally changed compared to the 19th century, and there is no going back.