Generic patterns in the evolution of urban water networks: Evidence from a large Asian city

Abstract

We examine high-resolution urban infrastructure data using every pipe for the water distribution network (WDN) and sanitary sewer network (SSN) in a large Asian city (≈4 million residents) to explore the structure as well as the spatial and temporal evolution of these infrastructure networks. Network data were spatially disaggregated into multiple subnets to examine intracity topological differences for functional zones of the WDN and SSN, and time-stamped SSN data were examined to understand network evolution over several decades as the city expanded. Graphs were generated using a dual-mapping technique (Hierarchical Intersection Continuity Negotiation), which emphasizes the functional attributes of these networks. Network graphs for WDNs and SSNs are characterized by several network topological metrics, and a double Pareto (power-law) model approximates the node-degree distributions of both water infrastructure networks (WDN and SSN), across spatial and hierarchical scales relevant to urban settings, and throughout their temporal evolution over several decades. These results indicate that generic mechanisms govern the networks' evolution, similar to those of scale-free networks found in nature. Deviations from the general topological patterns are indicative of (1) incomplete establishment of network hierarchies and functional network evolution, (2) capacity for growth (expansion) or densification (e.g., in-fill), and (3) likely network vulnerabilities. We discuss the implications of our findings for the (re-)design of urban infrastructure networks to enhance their resilience to external and internal threats.

Functional Topology of Evolving Urban Drainage Networks

“…These processes can occur in sequence or in parallel (Gudmundsson & Mohajeri, ; Mohajeri et al, ). Both processes contribute to an increase in total pipe length and number of network nodes in proportion to population (Krueger et al, ; Zischg et al, ). Water infrastructure also changes with retrofitting over time to accommodate growth, and changing design principles, regulatory requirements, financial constraints, etc.…”

“…The Oahu data are publicly available while the AAC data set was obtained under a confidentiality agreement from the water utility authority of the city. Node‐degree distribution and other topological metrics for AAC, based on dual mapping, were presented in Krueger et al (). Here we analyzed the largest sewershed in AAC (drainage area: ∼126 km 2 ; population ∼2.4 million) draining to a WWTP built around 1970.…”

A Century of Topological Coevolution of Complex Infrastructure Networks in an Alpine City

“…Previous studies using the dual mapping approach were mainly performed on road networks (RNs) [16][17][18], but some also on water distribution and urban drainage networks [19][20][21]. In principle, an extension to each network type is possible.…”

Emergent self-similarity and scaling properties of fractal intra-urban heat islets for diverse global cities

“…Spatial organization of physical assets, i.e., the urban form (e.g., impervious areas; buildings), as well as mobile assets such as automobile govern the distribution of heat sources in a city and modify the cooling effect of heat sinks. Prior research has shown that urban form has numerous fractal properties related to land use (Batty and Longley, 1994), urban infrastructure networks (Yang et al, 2017;Krueger et al, 2017), and impervious area (Chen, 2010;Makse et al, 1998). Similarly, the metabolic functions of cities (Oke, 1982) display scaling in the spatial patterns of population distribution, traffic, and energy use among others (Gonzalez et al, 2008;Rozenfeld et al, 2008;Bettencourt and West, 2010).…”