Vízügyi Közlemények, 1969 (51. évfolyam)

4. füzet - Rövidebb közlemények és beszámolók

(68) INTRODUCTION (For the Hungarian text see pp. 297) The present number, No. 3, September, Í969, of Hydraulic Engineering is devoted to problems associated with the quality ol water, with pollution control, with water treatment and purification of wastes. The decision to devote a complete number to these problems was prompted by the increasingly obvious fact that growing amounts of polluting substances are accumulated in the biosphere. Pollution in water and air alike may reach levels detrimental to health even at locations removed from the source ol pollution and prove injurious for future generations. This danger has been exposed in a striking manner at the conference held in September 1968, at the Paris headquarters of UNESCO, which was followed by the conference in Prague of the International Association l'or Pollution Research. The same subject will be dealt with in Hungary at the Budapest conference of the Hungarian Hydrological Society, to be held in November this year. In view of the significance attributed to these problems eight papers on research projets of general interest on pollution control have been selected from the work conducted at the Research Institute for Water Resources Development, Budapest for publication in No. 3 of Hydraulic Engineering scheduled to appear before the date of the Budapest conference. WATER POLLUTION By P. Benedek and B. Hock (For the Hungarian text see pp. 299) Data published in numerous papers both in Hungary and abroad have been syntlietized in Part 1 to present a general picture on pollution problems. In water pollution the role of industry is predominant, not only by its wastes discharged directly into the rivers, but also by the increasing mechanization and industrialization of agriculture and even domestic lii'e. Water is used by both industry and households as the carrier for removing the wastes produced and increasing water volumes are involved in this process of transportation towards the sea. Whereas in Hungary the average annual per capita water consumption is around 200 cu.m, this figure has soared e.g. in the United States already to 1200 cu.m. Drinking water consumption is expected to increase to 2.5 times of the present value within the coming 20 years, while industrial and agricultural consumption will grow 5 and 4 times, respectively within the same period. The increase in wastes volumes is accompanied by a steady deterioration of their quality. There are some micro-pollutants, hardly detectable by the methods of water analysis, which give rise to taste- and odour complaints and which are accumulated "imperceptibly" in human and animal organisms alike. Further grave consequences result from the growing concentrations of anorganic substances, salts, some of which are responsible for the cutrophication of lakes. Since sound, underground water resources are nearing exhaustion, diversions from polluted streams must be increasingly relied upon for domestic- and industrial supply. This involves increasingly complicated methods for water treatment. In spite of the persistent engineering efforts to keep pace with demands (desalination of seawater, creation of regional waterworks), prices for drinking water continue to soar. In the Federal Republic of Germany they have doubled during the last 13 years. Potential approaches to a solution of the problem have been reviewed in Part 2. The significance of water conservation policies and quality-selective water uses has been emphasised. Industrial plants can effectively reduce by efficient cooling and recirculation methods their water demand and the volume ol' wastes discharged, nevertheless water of drinking water quality should be supplied to households only, implying that parallel supply systems would be desirable. Within certain financial limits partial solutions can be arrived at by the retrieval of polluting wastes substances, but the responsibility for the removal of pollutants from the water rests even-