Hidrológiai Közlöny 1971 (51. évfolyam)

1. szám - Dr. Öllős Géza: A kutak vízhozamát befolyásoló tényezők

24 Hidrológiai Közlöny 1971. 1. sz. Special Conference Number, Szebellédy, L. 80—100 m from the bank, as was usual up to now. It will be an interesting problem of the future to determine the distance of the intereepting surfaces from the infiltration surfaces. The problem — in most cases — cannot be regarded as satisfactorily solved. In many instances the pollutants of river water and, in generál, an excessive accumulation of organic pollutants at the surface of infiltration, may result in the diminishing of dissolved oxygen in the water. The paper by Mrs. A. Homonnay lists a number of examples for such cases and their effects. Thus, for instance, she gives factual information on the increase of manganese content in the water of tűbe wells, and alsó on the change in mangenase content as a consequence of a change in the water level. An interesting observation was that in spring, at rising stages, the infiltrating water already rich in oxygen displaces the highmanganese water towards the wells. Considering the future possibilities of obtaining bank filtration water, as the evaluation of possible processes is no easv problem, the data and experiences eornerning the more highly polluted surface waters are of great interest. From this point of view the paper of J. Hollute and H. Sontheimer is especially welcome, as thev give information about the present situation of obtaining bank filtration water along the Rhine. On the basis of Fig. 16, for instance, the quality of Rhine-water and bank filtration water can be compared, revealing what degree of purification can be expected from the bank zone (in this particular case). As indicated, for example — somé of the trace elements are truly eliminated in the bank zone (e. g. mercury), — others, however, are eliminated mush less (e. g. lead). The paper — for obvious reasons — points out the worries caused by the increase in taste- and odour substances. An observation described in the paper deserving somé reflectionis: ". . .due to the increasing pollution in river waters, a fact already highly obvious on the Rhine, the water supply, from bank filtration zones, becomes increasingly difficult". This situation is likely to arise, in the future, along other rivers, too. It is therefore highly important to clear the process of bank filtration as thoroughly as possible, to be able to judge rationally the biological, etc. permissible load ot the aquiferous bank zone, the water regime of the area in question. In bank filtration water produetion, knowledge of the water volume obtainable from a bank zone 12 16 W 24 Goniometerangle ["] 28 32 36 W U 48 52 56 60 Bk 68 11 76 SO Fig. 16. Comparison of Rhine-water and the components of bank filtration water.