Includes bibliographical references.

Content-based active-set method for the pressure-dependent model of water distribution systems -- Empirical tool for the assessment of annual overtopping probabilities of dams -- Quantifying hydraulic and water quality uncertainty to inform sampling of drinking water distribution systems -- Promoting sustainable ice-jam flood management along the peace river and peace-athabasca delta -- Sensitivity analysis of an agent-based model used to simulate the spread of low-flow fixtures for residential water conservation and evaluate energy savings in a canadian water distribution system -- Eco-layouts in water distribution systems -- Real-time identification of cyber-physical attacks on water distribution systems via machine learning-based anomaly detection techniques -- Rainwater harvesting and artificial groundwater recharge in arid areas: case study in wadi al-alb, saudi arabia -- Discussion of "revisiting the resilience index for water distribution networks" by Gimoon Jeong, Albert Wicaksono, and Doosun Kang -- Erratum for "revisiting the resilience index for water distribution networks" by Gimoon Jeong, Albert Wicaksono, and Doosun Kang.

[Article Title: Content-Based Active-Set Method for the Pressure-Dependent Model of Water Distribution Systems / Jochen W. Deuerlein, Olivier Piller, Sylvan Elhay, and Angus R. Simpson, p.1-14]

Abstract: A new content-based, box-constrained, active-set projected Newton method is presented that solves for the heads, the pipe flows, and the nodal outflows of a water distribution system in which nodal outflows are pressure dependent. The new method is attractive because, by comparison with the previously published weighted least-squares energy and mass residuals (EMR) damped Newton method, (1) it typically takes fewer iterations, (2) it does not require damping, (3) it takes less wall-clock time, (4) it does not require the addition of any virtual elements, and (5) it is algorithmically easier to deal with. Various pressure-outflow relationships (PORs), which model nodal outflows, were considered and two new PORs are presented. The new method is shown, by application to eight previously published case study networks with up to about 20,000 pipes and 18,000 nodes, to be up to five times faster than the EMR method and to take between 34% and 70% fewer iterations than the EMR method.

https://doi.org/10.1061/(ASCE)WR.1943-5452.0001003

[Article Title: Empirical Tool for the Assessment of Annual Overtopping Probabilities of Dams / Javier Fluixá-Sanmartín, Luis Altarejos-García, Adrián Morales-Torres, and Ignacio Escuder-Bueno, p. 1-12]The tool was calibrated using the detailed overtopping models of 342,233 synthetic cases generated from 30 existing dams and then validated against a set of 21 independent cases. The tool is useful when analyzing a portfolio of dams in previous screening phases of dam risk analysis. It aims at identifying overtopping as a relevant failure mode and easily classifying each dam in terms of its overtopping probability. The tool is also a support for the definition and prioritization of corrective measures since it assesses their impact in the overtopping probability reduction.

Abstract:

https://doi.org/10.1061/(ASCE)WR.1943-5452.0001017

[Article Title: Quantifying Hydraulic and Water Quality Uncertainty to Inform Sampling of Drinking Water Distribution Systems / David Hart, J. Santiago Rodriguez, Jonathan Burkhardt, Brian Borchers, Carl Laird, Regan Murray, Katherine Klise, and Terranna Haxton, p. 1-13]

Abstract: Sampling of drinking water distribution systems is performed to ensure good water quality and protect public health. Sampling also satisfies regulatory requirements and is done to respond to customer complaints or emergency situations. Water distribution system modeling techniques can be used to plan and inform sampling strategies. However, a high degree of accuracy and confidence in the hydraulic and water quality models is required to support real-time response.

https://doi.org/10.1061/(ASCE)WR.1943-5452.0001005

[Article Title: Promoting Sustainable Ice-Jam Flood Management along the Peace River and Peace-Athabasca Delta / Prabin Rokaya, Howard Wheater, and Karl-Erich Lindenschmidt, p. 1-12]

Abstract: The regulation of rivers has always been a controversial issue, with potential benefits but also environmental impacts. In western Canada, the construction of W.A.C. Bennett Dam in the headwaters of the Peace River has raised concerns over the ecological health of the Peace-Athabasca Delta (PAD), a socioeconomically and ecologically important delta with national and international significance. The major concern is the reduced frequency of ice-jam floods, which are particularly effective in replenishing the high-elevation basins of the PAD. Previous studies have suggested that releasing water at opportune times from the dam could promote ice-jam flooding of the delta; however, ice-jam flood events can also be severe and devastating to riverside communities and economies.

https://doi.org/10.1061/(ASCE)WR.1943-5452.0001021

[Article Title: Sensitivity Analysis of an Agent-Based Model Used to Simulate the Spread of Low-Flow Fixtures for Residential Water Conservation and Evaluate Energy Savings in a Canadian Water Distribution System / Alexandre Tourigny and Y. Filion, p. 1-9]

Abstract: The results of a sensitivity analysis performed to examine the impact of uncertain parameters in an agent-based model (ABM) on the prediction of water use and energy use for pumping and water treatment in a distribution system are presented. The ABM was coupled with a water end-use model and the EPANET2 network solver to simulate word-of-mouth communication between water users and the adoption of water-efficient fixtures that lead to water use and energy savings in distribution systems. Three key ABM parameters (adoption probability, initial penetration rates, and connections per agent) were found to have an important impact on the adoption rate of low-flow fixtures.

https://doi.org/10.1061/(ASCE)WR.1943-5452.0001015

[Article Title: Iterative Hydraulic Interval State Estimation for Water Distribution Networks / Stelios G. Vrachimis, Stelios Timotheou, Demetrios G. Eliades, and Marios M. Polycarpou, p. 1-11]

Abstract: State estimation of hydraulics (i.e., pressure and flows) in water distribution networks is an important tool for efficient and resilient operation. However, hydraulic state estimation is a challenging task in practice due to the scarcity of measurements and the presence of several modeling uncertainties. Standard state estimation techniques may produce unreliable estimates with no information of the estimation error magnitude, especially when historical data are used in place of missing measurements. This paper proposes a comprehensive methodology for generating hydraulic state bounding estimates by considering both measurement and parametric uncertainties.

https://doi.org/10.1061/(ASCE)WR.1943-5452.0001011

[Article Title: Eco-Layouts in Water Distribution Systems / E. Cabrera, E. Gómez, J. Soriano, and R. Del Teso, p. 1-11]

Abstract: To achieve maximum efficiency in water pressurized transport, it is necessary to perform a global analysis, whenever possible starting from the system’s conception. The first stage of the process is the network layout, the main topic of this paper. The optimum topology from an energy point of view (or eco-layout) is the one that, insofar as is feasible, allows equalizing the network’s pressure to the set pressure standards. Eco-layouts can be easily designed in new systems but are difficult to implement, mainly in the short term, in operating networks.

https://doi.org/10.1061/(ASCE)WR.1943-5452.0001024

[Article Title: Real-Time Identification of Cyber-Physical Attacks on Water Distribution Systems via Machine Learning–Based Anomaly Detection Techniques / Ahmed A. Abokifa, Kelsey Haddad, Cynthia Lo, and Pratim Biswas, p. 1-11]

Abstract: Smart water infrastructures are prone to cyber-physical attacks that can disrupt their operations or damage their assets. An algorithm was developed to identify suspicious behaviors in the different cyber-physical components of a smart water distribution system. The algorithm incorporated multiple modules of anomaly-detection techniques to recognize different types of anomalies in the real-time monitoring and control data. Trained artificial neural networks were used to detect unusual patterns that do not conform to normal operational behavior.

https://doi.org/10.1061/(ASCE)WR.1943-5452.0001023

[Article Title: Rainwater Harvesting and Artificial Groundwater Recharge in Arid Areas: Case Study in Wadi Al-Alb, Saudi Arabia / Abed Alataway and Mohamed El Alfy, p. 1-13]

Abstract: Accelerated economic development in arid areas results in harmful stress on limited surface and groundwater resources. Flash flood and rainfall harvesting is a promising renewable resource. Using a theoretical water budget approach, this paper investigates groundwater recharge after a flash flood in three small dam reservoirs and one moderate-capacity dam reservoir in the Al-Alb basin, central Saudi Arabia. This approach is validated against water level measurements at five recharge wells. Watershed modeling of this basin was conducted using an analysis of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) digital elevation models, in which the morphometric variables were calculated. Landsat-8 and Spot-5 images from April 2015 were classified to identify different land-use and land-cover categories.

https://doi.org/10.1061/(ASCE)WR.1943-5452.0001009

[Article Title: Revisiting the Resilience Index for Water Distribution Networks / Gimoon Jeong, Albert Wicaksono, and Doosun Kang, p. 1-13]

Abstract: Water distribution systems (WDSs) are social infrastructures providing drinking water and must be capable of constant water supply while maintaining an appropriate water pressure. Hence, it is important to quantitatively evaluate the supply capacity of a WDS for design and operation purposes. As part of such efforts, several resilience indexes have been developed based on the energy flows within a network. Accurate estimation of a minimum required head at the demand node is critical for properly calculating the resilience indexes. This study proposes a novel approach of estimating the minimum required head, which considers the flow direction in pipes and the hydraulic gradient within a network.

https://doi.org/10.1061/(ASCE)WR.1943-5452.0000792