Vízügyi Közlemények, 1965 (47. évfolyam)
4. füzet - Rövidebb közlemények és beszámolók
'(12) HYDROLOGICAL CONDITIONS AND WATER RESOURCES MANAGEMENT IN THE NETHERLANDS By G. Santing M. Sc. (Eng.) Delft (For the Hungarian text see pp. 3) In his lecture delivered in October, 1964 in Budapest, the author, who is in the employment of Kijksinsiitut voor Drinkwatervoorziening, Den Haag, presented a picture of the technical and administrative aspects of water resources management and water supply in the Netherlands. Most detailed attention was devoted to hydrogeological problems, these constituting his special field of work, and consequently the problem of surface waters was inevitably neglected in comparison. He succeeded however in pointing to the difficulties which hydraulic management in the Netherlands is called upon to solve and to the methods with which such solutions are attempted. A detailed description of the material presented in the lecture will be omitted here, reference is made to the bibliography foreign to be found at the end of the Hungarian text, and only the backbone of the lecture will be reproduced : The 1 st Section is devoted to general hydrological conditions in the Netherlands , with special regard to interrelations between surface and underground waters. In Section 2 the water balance of the country is described, according to which the total average annual volume of water entering into the country may be estimated at 80.000 million eu.m, while the contribution of precipitation to water resources is, with evaporation subtracted, only 9,000 million cu.m. Overall annual resources may be put at 90,000 million cu.m. In Section 3 the problems of communal and industrial water supply are outlined. Difficulties in this field may be traced back to several causes: saltwater intrusion, pollution of watercourses, agricultural interests, requirements of recreation and nature conservation, land subsidence and the lack of storage opportunities. Section 4 gave an account of technical measures implemented for ensuring proper water supply, viz. of salt-water intrusion control, decentralization of pumping stations drawing on groundwater, groundwater recharging, utilization of bankfiltered river waters, the construction of reservoirs, together with various administrative regulations aiming at the practical realization of these objectives. Section 5 was devoted to problems encountered in other fields of water resources management, thus seepage in polder areas, hydraulic consequences of large scale sand excavation for roadbuilding purposes and unwatering of construction sites. Section 6 reported on research projects of major significance, among them on studies aiming at salt-water intrusion control, on theoretical investigations into groundwater movement in connection with forecasting consequences of artificial interference into groundwater household, studies on artificial groundwater recharging, evaporation, analogue studies and experiments for determining the regularities of groundwater movement, as well as various site investigations relating to the impermeability of surface reservoirs and to controlling pollution by leaking fuel oil tanks. INVESTIGATIONS OF DEEP BORED WELLS AND UTILIZATION OF INFORMATION GAINED IN WATER RESOURCES MANAGEMENT By Dr. Alföldi, Geologist (For the Hungarian text see pp. 42) Artesian waters have recently been included into the scope of water resources management. Boring of wells constitutes a task, which is inseparable from exploration, for which reason the necessary investigations must be performed with the greatest possible care. Results of investigations performed in single wells depend also on the technology of well drilling, since in loose, unstable waterbearing strata water under artesian pressure cannot be studied unless the well is filtered. Waterbearing layers,, through which the construction of a filter is intended must not be penetrated by
