“…Studies also have considered the influence of uncertainty in water demand (e.g., Berry et al, 2006;Comboul and Ghanem, 2012;Cozzolino et a., 2006Cozzolino et a., , 2011Mukherjee et al, 2017;Ostfeld and Salomons, 2005a, b;Shastri and Diwekar, 2006), and population density (Rico-Ramirez et al, 2007;Davis et al, 2013). Davis et al (2013) also considered the influence 15 of uncertainty in the rate of contaminant decay in a network following injection and uncertainty in the nature of the exposure model used to assess the consequences of a contamination event. We are not aware of any studies that have examined the influence on CWS design of uncertainties in the nature of the network itself, specifically the accuracy with which the network model used as the basis for designing a CWS represents the actual structure, the pipes and junctions, of the distribution system being considered.…”