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This paper presents a methodology for developing efficient and effective operational, short-time response to an unplanned failure event (e.g., a pipe burst or equipment failure) in a water distribution system (WDS). The proposed automated response methodology consists of isolating the failure event followed by the recovery of the affected system part by restoring the flows and pressures to normal conditions. The isolation is typically achieved by manipulating the nearby on/off valves. The recovery, which is the focus of this work, involves selecting an optimal combination of suitable operational interventions from a number of possible choices with the aim to reduce the negative impact of the failure (e.g., volume of water undelivered to consumers) over a prespecified time horizon. The intervention options considered here include valve manipulations, changing the pressure reducing valve's (PRV) outlet pressure, and installation and use of temporary overland bypasses from nearby hydrants in an adjacent, unaffected part of the network. The optimal mix of interventions is identified by using a multiobjective optimization approach driven by the minimization of the negative impact on the consumers and the minimization of the corresponding number of operational interventions (which acts as a surrogate for operational costs). This methodology has been applied to a real-world water distribution network of C-Town. The results obtained demonstrate the effectiveness of the proposed methodology in identifying the Pareto optimal intervention strategies that could be ultimately presented to the control room operator for making a suitable decision in near real time. [ABSTRACT FROM AUTHOR]

This paper provides an insight into behavior and effects of pressure reducing valves (PRVs) and of valves controlled in real time (RTC) during hydrant activation scenarios, which determine high-flow conditions in water distribution networks (WDNs). The analysis is carried out through the pressure-driven unsteady flow modeling of an Italian WDN, in which a pressure control device is assumed to be installed in the pipe outgoing from the source. Scenarios are constructed considering alternatively a PRV or an RTC valve, as pressure control device, and two different sites for hydrant activation. The results highlight that, thanks to its capability of controlling the service pressure at the critical node, the RTC valve performs better than the PRV, which is regulated based on its outlet pressure. In fact, the adoption of the RTC valve attenuates pressure deficits in the network, above all when the control time step is suitably small to attenuate pressure head oscillations at the controlled node. An additional benefit of RTC lies in increased outflows from the hydrant. The benefits of the RTC valve are smaller when the hydrant is activated in more redundant parts of the network, where pipe water discharge variations put the system to a less severe test. [ABSTRACT FROM AUTHOR]

Proper fire hydrant care—from installation to maintenance—will ensure years of operation. Most important, a well‐maintained hydrant will be ready and reliable when it's needed. [ABSTRACT FROM AUTHOR]

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Hydrant water supply is one of the most common water sources used by the fire fighters at fire scenes. The severe earthquakes in history were often accompanied by fires immediately. However, the fire departments were often stuck in the trouble of lacking water sources by the damage of water pipelines which worsened the fire-relieving work. Through the design of questionnaire, we have got some results of the actual preparations and integrations of fire departments. The results indicate that, over 80% of interviewees approve the establishment of 12 diversified fire water sources which combine natural water sources and artificial water sources; 87.7% of interviewees agree with the establishment and installation of fire-control water supply system especially belongs to the fire departments; About mastering the hydrant instantly supplying water state, 57.5% of interviewees choose the item of water at scene. About the reason of disapproving the fire water source should be listed on the management and checking options, most of interviewees agree that fire departments do not have the rights of water management. The most frequently chosen reason that the natural water sources from rivers within the jurisdiction are not listed on the regulation and checking options is that personnel are not easy to access the water source. In addition, the solution to the problem of the insufficient hydrants in some areas is to investigate in advance as priority. [ABSTRACT FROM AUTHOR]

On-demand collective irrigation networks are hydraulic systems designed to deliver and distribute irrigation water from the water source to the irrigation perimeter, while providing users with the flexibility to decide on the time, the duration and the frequency with which they intend to use their hydrant. This paper presents the newly developed software NIREUS, which is developed for implementing the performance analysis of such networks. The performance analysis with NIREUS gives an overview of the operational status of the network under study by implementing the model of the indexed characteristic curves, while on the other hand, NIREUS determines the pipes/hydrants of the network that present, or are most likely to present, operational problems by implementing the performance analysis at hydrant level. This information is particularly useful for the management of existing networks as well as for the planning of future interventions and rehabilitation activities. The paper also describes the main functions of NIREUS and the characteristics that differentiate it from other existing software. Moreover, a new indicator which is incorporated in NIREUS is presented, in which the whole magnitude of the operational efficiency of a hydrant is depicted. The validation of the new software is made through a comparative application of NIREUS and COPAM to an existing on-demand pressurized collective irrigation network. Results proved the usefulness of NIREUS in highlighting both the weak and the strong parts of the network. The validation procedure gave a very close approximation of the respective values calculated with COPAM with the relative error ranging between 0.0% to 0.36% for the indexed characteristic curve of C50 and 0.01% to 0.22% for the indexed characteristic curves of C70. [ABSTRACT FROM AUTHOR]

It can sometimes be difficult to think about 'everyday' objects, those things we are so familiar with that they become taken-for-granted aspects of the backdrop of our world. But what if those objects, despite their everydayness, are politically fraught and call for closer examination? I suggest that insights from two contemporary perspectives, postphenomenology and actor-network theory, are useful for drawing out the experiential, social, and political dynamics of everyday things. In this paper, I review and resituate several key concepts from these two theoretical frameworks and outline a method for using them together for the evaluation of technology. As a guiding example, I explore a paradigmatic everyday device: fire hydrants. Despite their everyday character, hydrants fulfill multiple social roles, some of them loaded with difficult and important political implications. [ABSTRACT FROM AUTHOR]

In the event that a contaminant is introduced to a water distribution system, utility managers must respond quickly to protect public health. Mitigation strategies specify response actions, such as warning consumers to reduce water activities using the news media and flushing contaminated water at hydrants. The performance of alternative response actions may be influenced by sociotechnical dynamics, as consumer reactions to contaminant exposure and information about the event can change water demands, hydraulics, propagation of a contaminant plume, and public health consequences. This research develops a modeling framework to test and evaluate mitigation decisions that a utility manager may take to protect public health over a wide range of contamination events. An agent-based modeling framework is developed to integrate social behaviors with technical artifacts in a sociotechnical model to evaluate the public health consequences of a water event. Social actors, including consumers and utility managers, are represented as agents and are coupled with a water distribution network model and a news media model to evaluate the performance of response strategies. Strategies for flushing hydrants are encoded as decision trees that specify the location and timing of hydrant flushing, based on the activation of water-quality sensors. The agentbased model is described using the Overview, Design, and Details protocol and is demonstrated for a virtual midsized municipality, Mesopolis. Results compare the effectiveness of flushing hydrants using cautious and adaptive response strategies and the use of the news media to disseminate warning messages. The framework can be applied for cities to evaluate alternative management strategies. [ABSTRACT FROM AUTHOR]

On-demand pressurized irrigation distribution networks (IDN) operating by gravity may face pressure failures especially during the peak period. Several methods have been developed for irrigation sectoring where farmers are organized in turns. In general, the optimization methods used for pressurized systems consider, in the formulation of the problem, energy saving as objective function, which is not suitable for gravity-fed networks. In this study, an optimization model for pressurized IDN fed by gravity was developed to provide an optimal operating strategy based on irrigation periods. The model uses genetic algorithm to assign an irrigation period to each hydrant taking into account the minimization of pressure deficit at the most unfavorable hydrant of the network. The method is applied to a large scale irrigation distribution network in Italy. It shows to significantly improve the hydraulic performance of the network by insuring a satisfactory pressure at all hydrants, under the actual peak demand as well as higher water demands. [ABSTRACT FROM AUTHOR]

The adoption of measures leading to higher efficiencies in the use of both water and energy in water distribution networks is strongly demanded. The methodology proposed combines a multi-objective approach and a financial analysis to determine de optimal design of pressurized irrigation networks which entails the minimization of both the investment cost and operational cost under three operating scenarios that incorporate energy saving strategies: 1- all hydrants operate simultaneously; 2- hydrants are grouped into sectors and irrigation turns are established; 3- the on-demand operation of the network is assumed. This methodology has been applied in a real irrigation network located in Southern Spain showing that the lowest overall design cost (investment and operational costs) is achieved in scenario 2. The comparison of the selected solutions in the three proposed scenarios with the current network design considering the total fulfillment of irrigation requirements showed that operational cost savings between 65% and 76% could be achieved. [ABSTRACT FROM AUTHOR]

As a critical element in preserving the health of urban populations, water distribution systems (WDSs) must be ready to implement emergency plans when catastrophic events such as contamination events occur. A risk-based simulation-optimization framework (EPANET–NSGA-III) combined with a decision support model (GMCR) is proposed in this study to determine optimal locations for contaminant flushing hydrants under an array of potentially hazardous scenarios. Risk-based analysis using Conditional Value-at-Risk (CVaR)-based objectives can address uncertainties regarding the mode of WDS contamination, thereby providing a robust plan to minimize the associated risks at a 95% confidence level. Conflict modeling by GMCR achieved an optimal compromise solution within the Pareto front by identifying a final stable consensus among the decision-makers involved. A novel hybrid contamination event grouping-parallel water quality simulation technique was incorporated into the integrated model to reduce model runtime, the main deterrent in optimization-based methods. The nearly 80% reduction in model runtime made the proposed model a viable solution for online simulation-optimization problems. The framework's capacity to address real-world problems was evaluated for the WDS operating in Lamerd, a city in Fars Province, Iran. Results showed that the proposed framework was capable of highlighting a single flushing strategy, which not only optimally reduced risks associated with contamination events, but provided acceptable coverage against such threats, flushing 35–61.3% of input contamination mass on average, and reducing average time-to-return to normal conditions by 14.4–60.2%, while employing less than half of the initial potential hydrants. [Display omitted] • Hydrant flushing is a practical way to deal with incidents of contamination. • Critical injection nodes, times, and durations are considered injection parameters. • Risk-based analysis using CVaR can address uncertainties about the contamination mode. • Hybrid event grouping-parallel water quality simulation reduces runtime dramatically. • GMCR with a comprehensive viewpoint shows promise in decision-making. [ABSTRACT FROM AUTHOR]

Water utilities excel when they place value on and maintain each system asset in a manner that reflects its value. An effective fire hydrant maintenance program offers a wide range of system benefits. [ABSTRACT FROM AUTHOR]

For understanding the leakage plugging and fire extinguishment characteristics of industrial solid waste-based composite foam slurry material (CFSM), the plugging effectiveness, thermal stability, and fire extinguishing and cooling process were analyzed systematically. The experimental device was designed to test the plugging effect of CFSM, when the thermal stability performance monitoring system and fire-extinguishing experimental platform were built to analyze the thermal stability, heat insulation properties, and extinguishment of CFSM, respectively. The results revealed that the surface temperature of CFSM with thickness more than 60 mm would not exceed the critical self-heating temperature of coal (60 °C) before reaching the equilibrium state of condensation heat, thus showing the good thermal insulation effect. The thermal conductivity of CFSM did not exceed 0.098 W/(m·k), indicating the excellent thermal insulation properties. The plugging experiments exhibited that the macroscopic plugging effect of CFSM with thickness more than 40 mm was less different from that of the completely sealed state, and the closed porosity of CFSM reached 74.5%, thus showing the well plugging performance. Moreover, the fire-extinguishing experiments indicated that CFSM could quickly flow and diffuse in burning coal, and exhibiting the well fire-extinguishing properties by covering the fire source, bonding-coating and lasting oxygen insulation. The study would provide an effective basis for the application of fire extinguishment technology using CFSM. • The hydration reaction mechanism of composite foam slurry material was exhibited. • The rheological characteristic of composite foam slurry material was investigated. • The diffusion law and equation of composite foam slurry material was obtained. • The bonding-reinforcement mechanism of this material was revealed. [ABSTRACT FROM AUTHOR]

The existence of fire hydrants in cities is of paramount importance in fighting, mainly to ensure water supply in vehicle stank sused by the fire department. In this sense, the present study a imed to analyse the distribution of such equipment in the south, east and West administrative areas of the city of Natal, Rio Grande do Norte (RN). In the first stage, the equipment was located through the Street View tool Google Earth software. The geographical coordinates were obtained through the Earth view mode and then, conferred in place through satellite navigation device (GPS - Global Positioning System). They were located and recorded 110 hydrants in the three regions. These records, using ArcGIS 9.3 software, was generated a vector file points and through ortofotocartas in scale 1:2000, the geographical location of each piece of equipment was adjusted and converted to projection Universal Transverse Mercator in SAD69 Datum and Zone 25 South. As spatial distribution analysis method, we used the kernel density estimator. The result observed was a geometrically irregular distribution of hydrants in the three administrative areas analysed, with some areas with great concentration and others with total lack of equipment. Thus, the use of this integrated tool to Geographic Information System - GIS proved to beuseful for the spatial location of hydrant sand to guide planning for the installation of new equipment in unmet areas, since it is essential equipment for human security and protect public and private property during fire fighting. [ABSTRACT FROM AUTHOR]