Vízügyi Közlemények, 1967 (49. évfolyam)

4. füzet - Rövidebb közlemények és beszámolók

(4 3) In the chapter on „Costs of Irrigation" diverse aspects of cost estimation are discussed. Cost components have been classified into two broad categories comprising costs of public supplied and operating expenses, respectively. Costs of a constant character and those varying proportionately with consumption have been distinguished. The constant cost of public supply is composed essentially of the depreciation and maintenance costs of pumping stations and underground pipe network, the basic electrical power rates, the salaries of the engineer controlling operation and the mechanics at the pumping stations. Variable costs comprise the rates for power and water actually consumed. The main items of the constant part of operating expenses include depreciation and maintenance charges after portable and auxiliary equipment, wages of the irrigation technician, as well as transportation costs of the irrigation technician, as well as transportation costs of the equipment to the field and back. The variable items of operating expenses, on the other hand, include labour costs for moving irrigation equipment from plot to plot. The basic principle underlying the cost estimation was that depreciation and maintenance charges after the state-owned supplying installations were entered in accordance with the new investment and crediting policy with 1.3% of the investment cost, rather than with the value corresponding to actual reduction in value and maintenance. Costs were affected materially by the orders issued in 1966 in connection with the determination of basic rates of power supply and depreciation charges on plant investment. The overall costs of irrigation are obtained from the above part-results. Cost-benefit analyses of irrigation should be based on averages for several years. About one-half of the costs is that for public supplies, while the other half for direct operating expenses. The share of constant costs is about 60%. Irrigation costs likely to occur in the case of consumption other than the average are shown in Fig. 2, in Fts per unit area, while in Fig. 3 in Ft/cu.m units. In Fig. 3 variations in the ratio of constant costs have also been entered. STUDIES ON THE INTERRELATIONS BETWEEN THE THERMAL SPRINGS AND WELLS IN BUDAPEST By T. Bäcker Eng.-Gol. (For the Hungarian text see. pp. 365) Thermal springs and wells are to be found in great numbers over the area of Budapest, on both sides of the Danube. The popularity of thermal baths in Budapest, as well as other potential utilizations of thermal water would justify efforts aimed at the development of production, yet at the same time further research is needed to obtain information on recharge conditions and interrelations between thermal wells. The fundamental problem in studies on interrelations was whether such interaction is possible under the particular geological conditions of the area. From the exploration of hydrogeological conditions and structural features of the basement communication between the two main karstic reservoirs with different pressure conditions has been positively established. The one on the right-hand side of the Danube has practically an open surface, while that on the left-hand side is under artesian pressure (Figs. 1 and 2). The main karstic water bearing Triassic, EoceneOligocene formations are highly pervious down to several hundred metres depth, which fact is not affected by the failure of the Népliget well drilled in 1966 ( Fig. 3). Communication between the two water systems is corroborated also by the reverse fault pattern ( Fig. 4) since the solid rock displays fissured, fractured character due to thrust forces. The intersections of structural elements, the so-called fault centers can be traced down to the basement. At these points wells of considerable yield can be drilled. A system consisting of karstic passages is characterized most suitable by the vein pattern. The introduction of a new well is consequently observed most readily along same main veins, i.e. fault systems and much less in wells situated between the fault zones.