The sewer as a bioreactor--a dry weather approach.

The sewer is a reactor for chemical and microbial transformations of wastewater. These in-sewer processes affect the quality of the wastewater and thereby the sewer itself, the subsequent treatment and the receiving water quality. The paper focuses on the interactions between the dry weather in-sewer chemical and microbial transformations of the wastewater and the corresponding processes in a downstream located treatment plant. A conceptual understanding of the sewer processes is crucial in this respect.