Vízügyi Közlemények, 2021 (103. évfolyam)
2021 / 2. szám - Introduction by the editors
10 Introduction by the editors For the last decade the most tumultuousness professional topic is the water management of the groundwater resources. A collective of nine professionals dealing with the topic from manifold aspects have prepared a thorough review in their paper “Problems in relation with the wells from the point of view of the sustainable groundwater management and protection The number of illegally built wells has gradually increased since 1990 as they present. Today 90-95% of the wells are built illegally by their estimation. They state that there is an overexploitation of groundwater bodies in substantial parts of Hungary that has a negative influence on the drinking water resources. Estimations show that about 20% of the water abstraction from the groundwater comes from unlicensed wells. The unlicensed and abandoned wells (there are even a million of them in the country) threaten the sustainability of the water uses. Legislation related to licencing of wells has not been based on professional basis. The legal water management organizations, that should act in licensing and controlling, cannot administer their tasks due to not cautious reorganisations. The authors make numerous recommendations - among them - registration of well pushers, direct supervision of well constructions, re-regulation of the training of well pushers, review of the licencing of the well drilling and development of a national well organization. The paper of Gábor Keve: “Measuringfluvial ice-cover by webcam ” presents the method developed by the author for processing the webcam observations of ice-drift carried out since 2002 along the lower Danube section of Hungary. The high frequency method of measurement provides an impartial way for the analysis of the pulsation of the ice-cover ratio in time and its daily run curve. The results of this research can be used in the ice forecast. The sluice gate of Rajka was constructed at the upstream end of Moson- Danube, by the bifurcation of the Danube, at the limits of village Rajka between 1905 and 1908. It was installed to control the water flow entering into the Moson-Danube from the main Danube and to prevent the former from the floods of the Danube. The paper by József Kertész describes the details of the hydraulic structure, the process of its design and construction. The paper presents the historical importance of the structure during the negotiations about the border after WW2, its role related to the new situation arose in the region with the construction of the Gabcikovo Barrage, as well as its role today. We publish two water management historical paper in this issue, both recall an event that happened 125 years ago. The millennium exhibition opened its gates on 1 May 1896 in the Budapest parkland (Városliget). It included Pavilion of Water
