Cooling-water effluents into polluted waters

The knowledge how cooling water effluents influence the waters has been extensively deepened during the past years. This applies mainly to heavily loaded waters which are subjected to many scientific investigations. Special attention is paid to the quality data for waters, which have been established by the water supply authorities and the power plant corporations. Together with model calculations, they do not only extend the conventional random test measurements by continuous recordings, they do however also show, how problematic these measurements unfortunately were, on which the statements of the water quality economy was based until today. With the discharge of cooling water into a water, four parameters with more or less extensive influence on the water quality are effective: lead-in of heat, oxygen content, entry of chemicals, vaporization. Their magnitude however is different, depending on the type of cooling of the concerned power plant. It also would be wrong to consider their effects each one isolated by itself, as it was done for a long time. Moreover they can only be judged and valuated by considering the close mutual relation. Wide ranged knowledge of the mentioned connections makes it possible today to harmonize the requirements for the protection of waters with the interests of the public energy supply and to obtain adaptable solutions. (orig.)