Sediment Origins, Deposition and Build-Up in Combined Sewer Systems

Abstract

The origins of sediments and associated pollutants found in sewers are clear, and demonstrable temporal and spatial variations have been found. It is likely that these variations are such that it is not possible to formulate general rules for the rates and nature of surface wash-in to sewers. Sanitary sources, however, are more amenable to deterministic assessment. The rates of build-up of sediments in sewers vary widely, and whilst it is possible to estimate the build-up in small-sized collector sewers, no general rules are yet available to predict the rate of deposition in larger sewers. There are broad similarities in the nature of sediments found in sewers in terms of particle size and pollutant characteristics. It is possible to formulate a pragmatic taxonomy for distinct classes of these sediments in order to facilitate understanding of sediment effects and to assist engineers with developing control strategies.

Field study of dynamic behaviour of sediment in combined sewer overflow chambers

“…Table 3, the sediment increase rates vary widely, because of the wide range of the various types of solids, the service area and the highly variable nature of in-sewer flow regimes, which are consistent with previous research (Ashley and Crabtree, 1992;Pisano et al, 1998). On the other hand, the results in Table 3 suggested that the sediment accumulation rate is high at first and then decreases gradually.…”

Notice of Retraction: Research on Sediment Movement Model and Sediment Pollution Load Model in Combined Sewer

“…(15)) [12]. The sewer sediment load model of the Cleveland City considered only the tube length, average slope and per capita flow, but the sewer sediment load model of the Fitchburg City and the Boston City considered average diameter of pipes, sewer service area, average slope of pipelines and total length of drain.…”

Horus, un modèle conceptuel de simulation de la pollution en réseau d'assainissement - structure et validation

“…Le modèle Horus comporte cinq modules principaux interconnectés et les algorithmes utilisés intègrent les récentes connaissances (ASHLEY et CRABTREE, 1992 ;VERBANCK ef al., 1994) en matière de production, de transport et de caractéristiques de la pollution particulaire (voir figure 1). Les différents algorithmes de génération et de transfert de la pollution du modèle ont été choisis en fonction des résultats du programme « Banc d'essai des algorithmes de modélisation de la pollution par temps de pluie » (ZUG ef al., 1998b).…”