Author(s): Antonietta Simone; Mariacrocetta Sambito

Linked Author(s):

Keywords: Sewer system; Water quality; Contamination; Monitoring

Abstract: The release and spread of contaminants into sewer networks are critical topics based on a complex process, whose management is sometimes very complicated due to the connective structure of these systems, which present a high number of potential entry points, thus requiring many analyses to identify the most probable emission areas. The need of defining computationally advantageous sampling designs that carries out the localization of contamination sources and allows the definition of intervention priorities is increasingly pressing. In order to manage such a situation, it is essential to understand and model dilution and dispersion phenomena of pollutants within the system in light of their connective structure. In this context, the present study proposes a strategy aimed at identifying nodes in sewer networks that have a high diffusion capacity, i. e. those nodes that, once contaminated, are able to propagate the contamination in a significant way due to their topological characteristics. These nodes, due to their strategic position in the network and their proximity to relevant nodes, dominate the contaminant diffusion processes. In fact, although they do not represent the most crossed nodes among all the paths towards the receptor, they represent points from which each contaminant has a greater probability of propagating in the network, and in this sense, they should be constantly monitored. The strategy is characterized by a two-step procedure which involves to: (i) evaluate the impact that the release of pollutants into a node has on the entire network using the depth-first search method algorithm. This information leads to the creation of a network contamination map; (ii) use a topological approach to define a ranking of importance of the network nodes with respect to their ability to spread information, and therefore pollutants. The contamination area of each node, defined in the previous step, is used as starting information in this analysis phase. Implementing information on the contamination capacity of each node makes the results of the analysis more effective compared to the selection of topological (e. g., Horton hierarchy) or hydraulic (e. g., lateral inflow) ones. Finally, to validate the performance of the strategy, it is applied to a literature sewer system used as benchmark.

DOI: https://doi.org/10.3850/iahr-hic2483430201-33

Year: 2024