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Abstract Designing urban water systems to respond to the accelerating and unpredictable changes of the Anthropocene will require changes not only to built infrastructure and operating rules, but also to the governance arrangements responsible for investing in them. Yet, inclusion of thispolitical‐economic feedbackin dynamic models of infrastructure systems and socio‐hydrology has lagged behindoperationalfeedback concerns. We address this gap through a dynamical systems application of the Coupled Infrastructure Systems (CIS) Framework, which provides the conceptual building blocks for analyzing social‐ecological systems through various classes of infrastructure and the flows of material and information among them. In the model, political‐economic feedback involves three decisions—infrastructure investment, rate‐setting, and short‐term demand curtailment—and each decision is constrained by institutional friction, the aggregation of decision and transaction costs associated with taking action. We apply the model to three cities in the Phoenix Metropolitan Area to compare how institutional friction interacts with a city's water resource portfolio and financial position to determine its sensitivity, or the degree to which its performance (e.g., providing sufficient supply to meet demand) changes given reductions in Colorado River water availability. We find that the slowing effect of institutional friction on investment and rate‐setting decisions can increase the sensitivity of a city's supply, but it can also promote objectives that compete with over‐response (e.g., rate burden). The effect is dependent on the initial operating capacity of the CIS and flexibility within the institutions, highlighting the need to consider political‐economic and operational feedback together when evaluating infrastructure systems.
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Urban Water Infrastructure Investment Model (PMA Version)
The Urban Water Infrastructure Investment Model (UWIIM) is a discrete time dynamical systems model designed to reflect the general flow of water, investment, and information in a stylized urban water coupled infrastructure system. The model couples operational considerations regarding the use of infrastructure, including storage, processing, and delivery infrastructure to meet annual demand given varying, user-defined, hydrologic inflows with political-economic considerations at play in three annual decisions: short-term (with a year) curtailment of demand, investment in infrastructure, and rate-setting. We demonstrate the model with representative configurations for three Phoenix Metropolitan Area (PMA) cities: Phoenix, Scottsdale, and Queen Creek. A detailed description of the model can be found in the attached Supporting Information document. The model uses the Julia programming language (version 1.8.4). The resources published here allow users to (i.) run the UWIIM for each of the three PMA cities and vary the parameters or initial conditions used and (ii.) replicate the sensitivity analysis performed in the referenced manuscript. Both tasks can be performed with the Jupyter notebooks or Julia code contained in the source code file. We also provide the raw outputs from the sensitivity analysis and R scripts used to produce the analysis figures displayed in the manuscript.
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- Award ID(s):
- 1923880
- PAR ID:
- 10520828
- Publisher / Repository:
- CUASHI Hydroshare
- Date Published:
- Edition / Version:
- 1
- Subject(s) / Keyword(s):
- infrastructure, dynamic modeling, urban water, political economy
- Format(s):
- Medium: X
- Institution:
- CUASHI
- Sponsoring Org:
- National Science Foundation
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