ABSTRACT
First of all, it is important to realize that, among engineers and practitioners, modeling related to sewers is normally understood as computer modeling aimed at analyzing the hydraulic performance. This type of modeling is often related to an analysis of stormwater runoff flows from urban and road surfaces. The objective of modeling related to this chapter is different. The focal point is an analysis of the overall chemical and microbiological performance of the sewer network using sewer process models. Here, the main point is an assessment of the impact of in-sewer chemical and biological processes in terms of, for example, hydrogen sulfide occurrence, odor nuisance, and concrete corrosion. As discussed in the preceding chapters, sewer processes do not proceed without potential negative impacts. In particular, hydrogen sulfide formation and anaerobic degradation of wastewater organic matter producing volatile odorous substances (VOCs) are often a major concern.
