Vízügyi Közlemények, 1964 (46. évfolyam)

4. füzet - IV. Perényi Károly: Héjcsatornák az öntözésben

(23) canal spécial, doivent être introduites après une épuration sommaire à l'aval des villes. Enfin les eaux usées industrielles qui ne sont pas dangereuses pour le réseau de la canalisation publique peuvent être déchargées par celle-ci, si sa capacité est suffisante (fig. 1). Le chapitre IV s'occupe du rendement d'exploitation rationel des services publiques. Les frais d'investissement spécifiques du réseau augmentent, du fait de l'accroissement du diamètre des conduites, proportionnellement avec l'étendue de l'agglomération. La plus grande densité de la population des grandes agglomérations a un effet en sens contraire, car la longueur moyenne du réseau par habitant diminue. Les frais d'exploitation du transport augmentent proportionnellement avec l'accroissement de la population. Suivant les résultats d'études poursuivies à l'étranger c'est dans une agglomération ayant 100 000 habitants que les frais spécifiques de la distribution d'eau sont les plus avantageux. Malgré cela on construit dans les agglomérations généralement une seule usine, car les conditions naturelles ne permettent pas n'importe quelle décentralisation, puisque dans les grandes unités les sollicitations maximales se compensent mieux et la continuité de la fourniture de l'eau peut être assurée également dans de meilleures conditions. REGIONAL WATER WORKS By G. Illés, Civ. Eng. (For the Hungarian text see pp. 105) Changes and anticipated values of the daily water demand in Hungary (Figs. 1 and 2) in the period from 1950 to 1980 can be characterized by the following data: in 1950 domestic w

rater 0,5 million, industrial water 1,8 million cu.m in 1960 domestic water 1,5 million, industrial water 5,0 million cu.m in 1980 domestic water 2,7 million, industrial water 15,0 million cu.m Adding to these the 5 — 600 cu.m/sec demand of agriculture, and comparing the total with the water resources of the country, which is concentrated in a few rivers and available underground, and taking further into consideration the modest storage opportunities of the country, it will be appreciated that water supply over the entire area of the country in the distant future is impossible, cannot be solved unless the water resources are developed on a regional basis covering large area units. Investigations by the author revealed 11 areas within the country where the construction of regional water works is already necessary. These areas are shown diagrammatically in Fig. 3. The fundamental principle underlying development scheduling is that in the first phase demands must be satisfied from local resources, the second phase comprising the development of regional water works, while the task of the third phase is the creation of water compensation systems extending to large parts, or even the entire area of the country, involving eventually international cooperation. A large number of possible solutions is usually available for conveying the water to the consumer. The alternative to be realized is the one involving the smallest investment and conveyance costs related to the unit of water produced. Both the consumers (F) and the water resources (V

) may be regarded as a spatial system of forces (Fig. 4) the relative positions of the point of attack of the resultants providing a basis for comparing the relative conveyance and investment costs for the pipelines. The basic condition of any solution is that EV Ш HF, the horizontal distance of conveyance T and the difference of the vertical ordinate of the points of attack M = Zf — Z у should be minimum. The water producing plants should be selected to meet these conditions. The trend of development is stated by the author to consist of the interconnection of the individual regional water works and of the gradual realization of cunational system of water works. By the end of the century the domestic water demand will have »increased by about 3 million cu.m/day, approximately the half of which can be met from local resources. The difference of 1,5 million cu.m/day must be conveyed by a pipeline system of about 1000 km total length and with diameters from 1000 to 1200 mm. The network would comprise a northern, a central and a southern