Some Considerations on River Pollution Mechanism

Abstract

The characteristics of the diffusion and transportation of suspended pollutant solids in rivers, based on the results of laboratory experiments and field observations, are discussed. First, in order to ascertain the effects of discharged sewage on the quality of downstream water, we studied analytically the changing rate of the concentration of pollutant matter in a river, and by comparing the theoretical results with experimental data, some quantitative relationships between the discharge of sewage and the dilution factor were obtained for two cases, one where the sewage is supplied intermittently to a river and soon distributed uniformly over the cross section, and the other where the effluent is discharged continuously from one side of the river. Secondly, the transportation mechanisms of pollutant matter from the Neya River, which is regarded as the main source of pollution for rivers and canals in Osaka City, were investigated, and a few practical remedies are proposed for reducing the degree of pollution in the waters of the Osaka area.