Vízügyi Közlemények, 1947 (29. évfolyam)

1-4. szám - VI. Szakirodalom

(18) 1. Drainage area of impervious character (Sign: A); 2. ,, ,, ,, semi-pervious „ (Sign: B); 3. ,, ,, ,, pervious „ (Sign: C). Drainage areas in the mountainous region investigated by the author are grouped according to the above table giving a complete list of areas of suitable topographical conditions to develop reservoirs. BOGDÄNFY's hydrological and the LÓCZY—TELEKI— PAPP geological maps may give some idea about the character of these drainage areas. Geological investigations extending to the whole of the drainage area are important not only for finding out all details of run-off, but also regarding erosion and sediment transportation, all in one, to avoid presumable silting in the reservoir. In Table III data by H. M. EAKIN are contained giving an informatory idea about silting of reservoirs in the U. S. A. Sediment transportation and silting can be largely decreased by afforestation as shown so clearly in Table IV ja for M с Millian reservoir. The effect of barrenness (deforestation and forest fires) is just the opposite as shown in Table IVjb. The size of reservoir is effected by the geological conditions of the basin and the narrow alike, on the one hand by seepage and on the other hand by statical reasons. These features are dealt with at length by the author. The stages of work are: 1. regional investigation, 2. geophisical examination, 3. detailed investigation (boring, etc.), 4. laboratory work. 2. Water Needed by Hydro-economical Interests of Greater Importance. Quantity of water needed for hydro-energy is dependent on the character of consumption as shown in Figure 8. Daily consumption in towns is indicated by Figure 9. Taking a constant head (M), needed water quantity (/) can be computed from the load with the application of Formula 13. If the reservoir be meant for balancing energy supplied by a power station without storage facilities, water consumption follows the lines of Figure 10. Quantity of water for irrigation is dependent on a) climatic conditions, b) physical and chemical peculiarities of the soil, and с

) nature of produced plants. Water quantity required by different plants during the production period is largely variable (See Figure 11). Water required by irrigation in Hungary has been thoroughly studied by Prof. E. NÉMETH (Budapest). By collating the hydxograph of a river with the diagram showing total quantity of water required by various plants (Figure 12) quantity and periodical distribution of water to be gained from the reservoir is resulted. In Figure 13 the author presents all his investigations into solving, through storage, the problem of irrigation in the Tisza-valley. Water required by navigation is dependent in the first place partly on natural flow, partly on presumable navigation seasons. The customary variations of computing storage area for flood control are given by Figure 14 (Formula 16). Before fixing the necessary storage capacity, a fundamental problem is to be solved: 1. Whether by holding back the floods through storage, any flood superposition is caused in the lower river sections, or not. 2. Subsequently the maximum flood is to be fixed. 3. This is followed by the computation of required storage capacity. 4. Finally the reduction caused by storage in catastrophic flood waters is to be computed. Consideration of losses arising between the reservoir and the site of utilization is very significant as also these losses are to be made up for by the reservoir. These losses are caused by: 1. evaporation, 2. seepage, and 3. storage in the river bed. The latter is no actual loss as the stored water becomes useful as soon as the water level decre-