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Natural disasters cause severe financial and life losses. Crisis management means purposefully pushing the flow of affairs into a manageable routine with the intention of returning them as soon as possible to pre -crisis conditions. Thus, the primary objective of this article is to present a model for the development of social capital in urban water crisis management. The research methodology employed in this study is descriptive -survey. Interviews and questionnaires were utilized to gather information, while data analysis was carried out using SPSS and TOPSIS software, the AHP analysis method, regression, and T-tests were used for analysis. The statistical population includes crisis and water managers of the country, as well as all residents of Karaj city )350 individuals based on Cochran's table). The results of the statistical analysis revealed that, according to the individuals in the sample, the level of social capital was below the desired threshold. Furthermore, there was a significant correlation observed between the indicators of social capital. The AHP analysis of the pairwise comparison of main criteria assigned priority to the indicators of social trust, with a coefficient of 0.433, followed by the incentive policy criterion and the change in attitude space, with a coefficient of 0.355. The interaction and value infrastructure of society received a coefficient of 0.277, while interaction alone received a coefficient of 0.203. Finally, the criteria of non -alienation with the government with coefficient of 0.199 showed the fifth priority, with a coefficient of 0.199. The study demonstrates that a country's ability to respond to crises is closely linked to its crisis management policies. Promoting social capital within society and fostering a spirit of cooperation and active participation among the population are crucial solutions. [ABSTRACT FROM AUTHOR]

Turbidity stands as a crucial indicator for assessing water quality, and while turbidity sensors exist, their high cost prohibits their extensive use. In this paper, we introduce an innovative turbidity sensor, and it is the first low-cost turbidity sensor that is designed specifically for long-term stormwater in-field monitoring. Its low cost (USD 23.50) enables the implementation of high spatial resolution monitoring schemes. The sensor design is available under open hardware and open-source licences, and the 3D-printed sensor housing is free to modify based on different monitoring purposes and ambient conditions. The sensor was tested both in the laboratory and in the field. By testing the sensor in the lab with standard turbidity solutions, the proposed low-cost turbidity sensor demonstrated a strong linear correlation between a low-cost sensor and a commercial hand-held turbidimeter. In the field, the low-cost sensor measurements were statistically significantly correlated to a standard high-cost commercial turbidity sensor. Biofouling and drifting issues were also analysed after the sensors were deployed in the field for more than 6 months, showing that both biofouling and drift occur during monitoring. Nonetheless, in terms of maintenance requirements, the low-cost sensor exhibited similar needs compared to the GreenSpan sensor. [ABSTRACT FROM AUTHOR]

This study presents the first report of per‐ and polyfluoroalkyl substances (PFAS) in water samples collected in the Arroyo Colorado (n = 15), irrigation canals (n = 6), stormwater and wastewater retention ponds (n = 7), as well as drinking waters (n = 2) across the Arroyo Colorado watershed. Of the 30 PFAS monitored in this study, 14 were detected in the samples in various combinations. Short‐chain PFAS (less than 8 carbon atoms) were observed in most samples. Water collected from the Arroyo Colorado showed significant spatial variabilities, with high total PFAS concentrations observed near possible point sources ‐ a municipal airport and wastewater treatment facilities. PFAS concentrations were generally higher in water samples collected in stormwater and wastewater retention ponds than in the Arroyo Colorado and irrigation canals. PFAS in stormwater retention ponds likely came from roadway runoff. Short‐chain PFAS were observed in the two municipal water samples, but they were below the current U.S. EPA regulation limits or are not currently regulated. This study provides useful information for water quality in this region and provides insights into PFAS occurrence in a rapidly urbanizing area. [ABSTRACT FROM AUTHOR]

Urban surface water is increasingly used for contact recreation. Predicting Escherichia coli (E. coli) concentrations in these waters can support early warning of bathers and explain the dynamics of this faecal pollution indicator. This study provides the first overview of the scientific knowledge on E. coli prediction models for freshwater in cities. Modelling techniques for urban waters are comparable to those for other freshwater environments, with multiple linear regression being the most frequently used approach. While previously reviewed E. coli prediction models for freshwater beaches predominantly target lakes, urban models mainly target rivers. We found indications that model performance for urban rivers is lower than for recreational beach water in rivers in general. Reported performance metrics indicate that not all relevant sources are captured by the models. Future research should solve the lack of insight into model performance for specific applications and verify the suggested directions to improve models' accuracy. [ABSTRACT FROM AUTHOR]

Privatization and remunicipalization have been used as alternative options to reform the delivery of local public services; in both cases, mainly because of disappointment with the service performance, although ideological preferences might also play a role. The drivers and effects of water privatization have been widely studied, whereas little empirical evidence is available for remunicipalization, particularly regarding its effects. Using a sample of Spanish municipalities, this paper assesses the change in the price of urban water following remunicipalization as compared to privatization. The main finding is that remunicipalization leads to smaller increases in price; this outcome is, however, due to a few atypical municipalities with abnormally low prices before the policy reform. Once these influential observations are controlled for, whether the reform consists of remunicipalization or privatization makes no difference regarding price changes. It is also found that remunicipalization is much more likely in cities governed by extreme left-wing parties. [ABSTRACT FROM AUTHOR]

Copyright of World Water Policy is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Denmark's complete reliance on groundwater for water supply presents a unique case study in management of natural resources, urban planning, and water resilience in the face of climate change. This paper examines the groundwater management strategies in Denmark in general, focusing on Denmark's four largest cities—Copenhagen, Aarhus, Odense, and Aalborg— each facing distinct challenges due to their demographic, geographical, hydrogeological, and economic characteristics. Through analysis of these cities' approaches to groundwater management, this research contributes to the global discourse on sustainable urban water supply systems. As coastal groundwater cities (CGC), these urban areas must navigate the complexities of sustaining growing populations, mitigating climate change impacts, and coastal processes while ensuring the long-term viability of their groundwater resources. Copenhagen and Aalborg, built atop semi-confined fractured and locally karstic carbonate rocks, highlights the specific challenges associated with karstic groundwater systems, while, Aarhus, and Odense built on glaciofluvial aquifers faces different issues. The different groundwater challenges in these cities underscores the importance of integrating urban development with water resource management and environmental sustainability, offering valuable insights and lessons learned for other regions facing similar challenges. This study, thus not only sheds light on Denmark's groundwater management practices, but also emphasizes the need for innovative solutions to ensure the resilience of urban water supply systems in a changing climate and increasing pressures of emerging organic contaminants and elevated concentrations of geogenic elements induced by water abstraction and fluctuating water tables. Advanced Danish monitoring and modelling tools applied to support decision-making and innovation within the water sector are continuously developed and improved to support resilient and sustainable management of the available water resources.

Water security is a multi-faceted concept that encompasses dimensions such as water quantity, quality, human health, well-being, water hazards, and governance. The evaluation of water security is an important step towards understanding and improving it, particularly in urban settings where disparities resulting from unequal distribution of population and resources are present and often evade citywide assessments. To address the diversity of the urban space, we propose a multi-level assessment approach based on downscaling the spatial dimension. Using a comprehensive indicator-based framework, we evaluate the city of Campinas in Brazil across citywide and intra-city scales. Employing the Theil index to measure inequality, the results reveal nuanced disparities less apparent at broader scales. Despite an overall favourable water security condition, spatial heterogeneity is still noticeable in the urban area of Campinas. The methodology highlights different aspects, such as vegetation cover, social green areas, and wastewater collection, which are inequitably distributed in the urban area. This integrated approach, linking inequality and water security assessment, has the potential to unveil specific needs within urban areas, helping guide targeted interventions to improve water security levels for all. HIGHLIGHTS A multi-disciplinary urban security assessment framework is applied through three scales in the urban area: citywide, regions and sector.; Theil index is used to measure inequality in terms of water security.; Downscaling the urban water security analysis facilitates the exposure of disparities, providing useful information for decision-makers on local needs.;

BACKGROUND AND OBJECTIVES: Environmental degradation, especially that related to water, has the potential to result in an unhealthy life. Humans drinkable water for basic needs, but poor water quality can cause disease. One of the solutions of households to obtain drinkable water is to subscribe to water companies. This study presents the notion of community engagement related to urban drinkable water supply, specifically by examining the willingness of community members to pay for such services in response to environmental pressures. METHODS: This study used purposive sampling methods to determine the value of willingness to pay, identified challenges in the community through a questionnaire on drinkable water in Jakarta, Indonesia, and conducted estimation using ordinary least squares. This research used a sample of 503 households in Jakarta. FINDINGS: The coefficient values of the control variables, namely, daily income (0.448), education level (4.344), and age (628.1), exhibited a positive correlation and statistically significant impact. Results indicate a positive and statistically significant association between the coefficient values of the variables of interest, namely, water quality (8.663) and water source (21.248), in willingness to pay for drinkable water. A one-unit increase in the coefficient score impacts the willingness to pay value, measured in Indonesian rupiahs. Findings indicate that the majority of the respondents expressed readiness to pay for drinkable water valued below 100,000 Indonesian rupiah per month, which is equivalent to under 6.30 United States Dollars. The suggested strategies for addressing the diverse issues encompass the necessity of implementing structural reforms involving the engagement of local leaders to enhance empowerment. This approach holds promise for effectively resolving the drinkable water crisis. Technical effort in shaping the behavior of urban communities in using and appreciating water is also essential to sustain the environment. CONCLUSION: Environmental contamination issues have become a reason for households to subscribe to water companies. Customers are willing to pay to obtain clean and potable water. This study is essential as a basis for formulating policies that can be used by drinkable water companies regarding community members' ability to pay for water, preferences, and participation in protecting the environment. [ABSTRACT FROM AUTHOR]

Due to the increasing pressures of global change, such as urbanization, climate change, population growth, and socioeconomic changes, cities around the world are facing significant water challenges, both in terms of supply and quality. This emphasizes the need for concerted effort to manage water supplies effectively for sustainable development. The driver, pressure, state, impact, and response (DPSIR) model was applied in this study to determine the underlying causes of Addis Ababa's water supply and quality issues. Field observations, key informant interviews, and previously published reports were used to identify these variables, impacts, and coping mechanisms. The model suggests that issues with urban water are caused by inadequate waste management, fast urbanization, climate change, sociodemographic shifts, economic challenges, changes in land use and land cover, and institutional pressures. As a result, aquatic ecosystems endure damage and there is also an increase in water-related diseases and unmet water demand. Some of the responses to these effects include using bottled water, digging boreholes, harvesting rainwater, planting trees, and soliciting funds. The study concludes by recommending an integrated approach to managing the risks of declining water quality and shortage. This study will advance the important empirical understanding of how urban water supply and quality are impacted by environmental stresses on a global scale. It will also positively impact the development of sustainable water management policies and practices. [ABSTRACT FROM AUTHOR]

Irrigated urban agriculture (IUA) is important for urban food systems and livelihoods but has many unknown socio-technical configurations. This article examines the dynamics of farm irrigation and associated sociotechnical arrangements in the Nairobi catchment. The research shows that there are five principal forms of IUA, differentiated according to land sizes, water sources and suitability, technicality, actors, and market orientation. The city service does not provide arrangements for hydraulic infrastructure or agricultural extension, and state agencies do not take IUA practices into account. The complexity of the socio-technical configurations calls for flexible governance arrangements that go beyond the established models. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Environmental degradation, especially that related to water, has the potential to result in an unhealthy life. Humans drinkable water for basic needs, but poor water quality can cause disease. One of the solutions of households to obtain drinkable water is to subscribe to water companies. This study presents the notion of community engagement related to urban drinkable water supply, specifically by examining the willingness of community members to pay for such services in response to environmental pressures.METHODS: This study used purposive sampling methods to determine the value of willingness to pay, identified challenges in the community through a questionnaire on drinkable water in Jakarta, Indonesia, and conducted estimation using ordinary least squares. This research used a sample of 503 households in Jakarta.FINDINGS: The coefficient values of the control variables, namely, daily income (0.448), education level (4.344), and age (628.1), exhibited a positive correlation and statistically significant impact. Results indicate a positive and statistically significant association between the coefficient values of the variables of interest, namely, water quality (8.663) and water source (21.248), in willingness to pay for drinkable water. A one-unit increase in the coefficient score impacts the willingness to pay value, measured in Indonesian rupiahs. Findings indicate that the majority of the respondents expressed readiness to pay for drinkable water valued below 100,000 Indonesian rupiah per month, which is equivalent to under 6.30 United States Dollars. The suggested strategies for addressing the diverse issues encompass the necessity of implementing structural reforms involving the engagement of local leaders to enhance empowerment. This approach holds promise for effectively resolving the drinkable water crisis. Technical effort in shaping the behavior of urban communities in using and appreciating water is also essential to sustain the environment.CONCLUSION: Environmental contamination issues have become a reason for households to subscribe to water companies. Customers are willing to pay to obtain clean and potable water. This study is essential as a basis for formulating policies that can be used by drinkable water companies regarding community members’ ability to pay for water, preferences, and participation in protecting the environment.

Bioretention practices have become a common way to protect natural waterways in urban and suburban landscapes across the United States. However, optimal design, implementation, operation, and maintenance are still in need of study. A field survey of 52 bioretention practices was conducted in Davidson County, Tennessee, to address research questions related to operation and maintenance. A suite of site conditions were documented, such as size, signs of erosion, and dominant surface cover. Samples were collected from the surface of the engineered media layer and analyzed for organic matter content and bulk density. Vegetation was described in terms of dominant species and canopy cover. On average, the organic matter content of media under plant‐based mulch cover was significantly greater than that under rock cover (p = 0.002). Bulk density of the surface media is strongly and inversely correlated to organic matter content; bulk density did not generally vary with bioretention area age and was highly variable within treatments. On average, the bulk density of the media under the plant‐based mulch cover was significantly less than that under the rock cover. Media under the composite treatments had similar bulk density to both the plant‐based mulch (p = 0.233) and the rock covers (p = 0.132). Plant canopy did not surpass 70% in practices with bulk density values above 1.55 g/cm3. These results suggest that consideration should be made regarding the tradeoffs between utilizing rock coverings and potential for plant establishment impacts. [ABSTRACT FROM AUTHOR]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Climate change and increasing water demand in urban environments necessitate planning water utility companies' finances. Traditionally, methods to estimate the direct water utility business interruption costs (WUBIC) caused by droughts have not been clearly established. We propose a multi-driver assessment method. We project the water yield using a hydrological model driven by regional climate models under radiative forcing scenarios. We project water demand under stationary and non-stationary conditions to estimate drought severity and duration, which are linked with pricing policies recently adopted by the Sao Paulo Water Utility Company. The results showed water insecurity. The non-stationary trend imposed larger differences in the drought resilience financial gap, suggesting that the uncertainties of WUBIC derived from demand and climate models are greater than those associated with radiative forcing scenarios. As populations increase, proactively controlling demand is recommended to avoid or minimize reactive policy changes during future drought events, repeating recent financial impacts. [ABSTRACT FROM AUTHOR]

Regional cities are having their unique water security challenges due to regional urban water contexts, regional socio-economic structure, and climate conditions. Regional urban community's perceptions of water usage are expected to be different from the communities in large metropolitan cities. The city of Townsville is the largest regional city in the northern tropical region of the state of Queensland in Australia, and it is known to have its unique dry tropic climate condition. The city faced a water crisis due to a prolonged drought in 2013–2018. As part of this research, at first, a literature review was conducted to understand what water demand management (WDM) tools worked well during urban water crisis in different parts of the world. This paper then investigates how residential water usage changed with the changes in drought measures in the city of Townsville in the last decade. A minimum per capita residential water requirement is established for the study region to benchmark the effects of tools implemented in the region. The paper investigates the WDM policies implemented in the city of Townsville including when the policies were applied and the impacts and efficacy of these policies before water crisis, during water crisis and after water crisis. The most effective WDM tools identified are water restrictions, public awareness raising and education programmes. The impacts of water restriction policies and the perceptions of local water professionals on their success elements are also studied. The results are compared and the reasons behind the findings are investigated. [ABSTRACT FROM AUTHOR]

In the face of urban expansion, ensuring sustainable water consumption is paramount. This study aims to develop a domestic water demand forecast model that considers population heterogeneity and the urban area distribution in a city in the Brazilian Semiarid Region. The methodology comprises three main steps: (1) spatial data collection to identify explanatory variables for a future Land Use and Cover (LULC) model; (2) simulation of LULC data for 2030, 2040, and 2050 using the MOLUSCE plugin; and (3) estimation of domestic water demand based on projected urban area expansion and a linear regression model incorporating demographic indicators of household income, residents per household, total population, and gender. The results demonstrated a consistent LULC simulation, indicating an urban expansion of 4 km2 between 2030 and 2050, with reductions of 0.6 km2 in natural formations and 3.4 km2 in farming areas. Using LULC data, the study predicted a 14.21% increase in domestic water consumption in Campina Grande for 2050 compared to 2010, equivalent to an increase of 2,348,424.96 m3. Furthermore, the spatial analysis draws a spatial profile of water consumption among residents, highlighting the areas with the highest per capita consumption. Thus, this research offers a consistent approach to estimating water demand in regions with limited consumption data, providing valuable insights for decision-makers to consider in urban planning. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: In this era of globalization, clean water management is considered a complex problem requiring the strategic management of various aspects. Citizen participation in managing polluted waters is a critical, determining factor in preventing water crises. This study predicts the socioeconomic factors influencing citizens’ behaviors in polluted water management.METHOD: A survey on Jakarta’s clean water was conducted with 503 respondents in 2022. Three interest variables were studied: first action taken during contamination, water nuisance level, and willingness to pay for clean water. Control variables were also explored, including daily income, education level, age, marital status, and gender. Data were analyzed using logistic regression.FINDINGS: In general, socioeconomic factors influence citizens’ behaviors in dealing with polluted water. The specific findings regarding the probabilities for the first action on the basis of asking for immediate action from local authorities, namely, by asking other citizens, waiting for information from other citizens, and looking for sources of water pollution were –2.21, –3.50, and 0.61, respectively. The results also revealed the probabilities of nuisance level (0.07), willingness to pay for clean water (0.0495), daily income (–0.02), educational level (–0.429), and age (0.01). The probabilities for married citizens (–2.845) and men (–0.268) were lower than those for unmarried citizens and women, respectively.CONCLUSION: The findings of this study can be used to predict the management of water pollution among Jakarta citizens, as well as serve as a reference for related stakeholders. Socioeconomic factors can affect citizens in various aspects of life, including participation in water management. However, not all socioeconomic factors are directly proportional to citizen participation. In fact, other socioeconomic indicators are inversely proportional to what are expected based on theoretical assumption. Finally, educational level and income do not always translate to behavioral changes linked to water pollution management.

Nature-based Solutions (NbS) were introduced by the IUCN for the first time, but today have different definitions in the literature. NbS are deemed the key to urban sustainability and aim to enhance the built environment through ecological and environmental interventions to support the built environment for future extremes of climate change and related hazards. NbS include blue and green infrastructures, ecological engineering, ecosystem services and ecosystem-based adaptation. Various frameworks defined different key considerations and the literature suggests plenty of frameworks towards successful NbS applications. Current debates critique the extent to which innovative and adaptive the solutions are, whether they are implemented by considering social values and social equity, and the financial burden they often bring which strengthens the disparities between the world cities. Uncontrolled urbanization often causes cities to become an environmental problem. This paper conducts a literature review to lay out the current debates and to highlight the multidimensionality of NbS. It focuses on the potential of NbS in disaster risk reduction and so the paper draws a framework to successfully implement and provide improvements for NbS based on the theoretical ground. NbS are investments in the life quality of the residents and preventive tools in the risk management of cities. The paper attempted to frame the NbS clearer for scholars interested in the subject.

Turbidity stands as a crucial indicator for assessing water quality, and while turbidity sensors exist, their high cost prohibits their extensive use. In this paper, we introduce an innovative turbidity sensor, and it is the first low-cost turbidity sensor that is designed specifically for long-term stormwater in-field monitoring. Its low cost (USD 23.50) enables the implementation of high spatial resolution monitoring schemes. The sensor design is available under open hardware and open-source licences, and the 3D-printed sensor housing is free to modify based on different monitoring purposes and ambient conditions. The sensor was tested both in the laboratory and in the field. By testing the sensor in the lab with standard turbidity solutions, the proposed low-cost turbidity sensor demonstrated a strong linear correlation between a low-cost sensor and a commercial hand-held turbidimeter. In the field, the low-cost sensor measurements were statistically significantly correlated to a standard high-cost commercial turbidity sensor. Biofouling and drifting issues were also analysed after the sensors were deployed in the field for more than 6 months, showing that both biofouling and drift occur during monitoring. Nonetheless, in terms of maintenance requirements, the low-cost sensor exhibited similar needs compared to the GreenSpan sensor.

The City of Cape Town experienced a serious drought between 2016 and 2018 which led to severe water shortages and concerns for the environment. This study took advantage of a period of unprecedented levels of awareness about water security in order to investigate households' willingness to pay (WTP) for reliable water supply and their WTP to avoid environmental damages in securing this supply. Increasing the supply of water from dams and groundwater will ultimately impact on aquatic ecosystems, but alternatives are more expensive. We surveyed 248 households from 105 suburbs and used contingent valuation methods to investigate WTP for both secure and less damaging or 'greener' ways of supplying water. Depending on income level, households were willing to pay 63-127% more for their normal levels of consumption in order to have security of supply, and a further 35-68% more to ensure its environmental sustainability. Based on the relationship between WTP for 7 income categories, the overall WTP for secure water supply under nondrought conditions amounted to some 2.8 billion ZAR/year, which is about 90% higher than pre-drought revenues. Aggregate WTP for securing this supply using options that ensured the protection of the region's rivers and estuaries was 3.3 billion ZAR. These results have an important bearing on water investment and pricing decisions over the longer term. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: In this era of globalization, clean water management is considered a complex problem requiring the strategic management of various aspects. Citizen participation in managing polluted waters is a critical, determining factor in preventing water crises. This study predicts the socioeconomic factors influencing citizens' behaviors in polluted water management. METHODS: A survey on Jakarta's clean water was conducted with 503 respondents in 2022. Three interest variables were studied: first action taken during contamination, water nuisance level, and willingness to pay for clean water. Control variables were also explored, including daily income, education level, age, marital status, and gender. Data were analyzed using logistic regression. FINDINGS: In general, socioeconomic factors influence citizens' behaviors in dealing with polluted water. The specific findings regarding the probabilities for the first action on the basis of asking for immediate action from local authorities, namely, by asking other citizens, waiting for information from other citizens, and looking for sources of water pollution were -2.21, -3.50, and 0.61, respectively. The results also revealed the probabilities of nuisance level (0.07), willingness to pay for clean water (0.0495), daily income (-0.02), educational level (-0.429), and age (0.01). The probabilities for married citizens (-2.845) and men (-0.268) were lower than those for unmarried citizens and women, respectively. CONCLUSION: The findings of this study can be used to predict the management of water pollution among Jakarta citizens, as well as serve as a reference for related stakeholders. Socioeconomic factors can affect citizens in various aspects of life, including participation in water management. However, not all socioeconomic factors are directly proportional to citizen participation. In fact, other socioeconomic indicators are inversely proportional to what are expected based on theoretical assumption. Finally, educational level and income do not always translate to behavioral changes linked to water pollution management. [ABSTRACT FROM AUTHOR]

Nature-based Solutions (NbS) were introduced by the IUCN for the first time, but today have different definitions in the literature. NbS are deemed the key to urban sustainability and aim to enhance the built environment through ecological and environmental interventions to support the built environment for future extremes of climate change and related hazards. NbS include blue and green infrastructures, ecological engineering, ecosystem services and ecosystem-based adaptation. Various frameworks defined different key considerations and the literature suggests plenty of frameworks towards successful NbS applications. Current debates critique the extent to which innovative and adaptive the solutions are, whether they are implemented by considering social values and social equity, and the financial burden they often bring which strengthens the disparities between the world cities. Uncontrolled urbanization often causes cities to become an environmental problem. This paper conducts a literature review to lay out the current debates and to highlight the multidimensionality of NbS. It focuses on the potential of NbS in disaster risk reduction and so the paper draws a framework to successfully implement and provide improvements for NbS based on the theoretical ground. NbS are investments in the life quality of the residents and preventive tools in the risk management of cities. The paper attempted to frame the NbS clearer for scholars interested in the subject. [ABSTRACT FROM AUTHOR]

With the increase in climate and social change, the issue of water security in cities is becoming more highlighted and urban decision makers are paying attention to issues such as water productivity and reuse of sewage to achieve sustainable municipal water management. In this study, a framework of urban water metabolism was developed based on the water balance. The water flow patterns in the urban areas examined and the performance of water management in Isfahan was evaluated. In this article, previous equations of urban water metabolism reviewed and new relationships were defined by adding parameters such as Non-revenue water, taking into account the conditions of urban water management in developing countries such as Iran. The developed water metabolism model was first used on Isfahan city as a real sample for 2019 and the pattern of water use and urban water performance of Isfahan were analyzed. The city of Isfahan is largely dependent on surface water (water of the Zayandeh-Rud Dam and River), While having a lot of domestic consumer, it has a high potential in terms of gray water and treated wastewater. Studies showed that more than 80% of Isfahan's water requirement is provided from foreign sources, and this indicates that Isfahan's sustainable water supply is weak and there is severe dependence on the surrounding areas for water supply. These results show that the water metabolism framework helps to facilitate more comprehensive understanding and evaluations of city water performance.

We designed an out-of-water radar water velocity and depth sensor, which is unique due to its low cost and low power consumption. The sensor is a first at a cost of less than USD 50, which is well suited to previously cost-prohibited high-resolution monitoring schemes. This use case is further supported by its out-of-water operation, which provides low-effort installations and longer maintenance-free intervals when compared with in-water sensors. The inclusion of both velocity and depth measurement capabilities allows the sensor to also be used as an all-in-one solution for flowrate measurement. We discuss the design of the sensor, which has been made freely available under open-hardware and open-source licenses. The design uses commonly available electronic components, and a 3D-printed casing makes the design easy to replicate and modify. Not before seen on a hydrology sensor, we include a 3D-printed radar lens in the casing, which boosts radar sensitivity by 21 dB. The velocity and depth-sensing performance were characterised in laboratory and in-field tests. The depth is accurate to within ±6% and ±7 mm and the uncertainty in the velocity measurements ranges from less than 30% to 36% in both laboratory and field conditions. Our sensor is demonstrated to be a feasible low-cost design which nears the uncertainty of current, yet more expensive, velocity sensors, especially when field performance is considered. [ABSTRACT FROM AUTHOR]

Urban water systems across the world are grappled with growing social and environmental pressures. To address these pressures, a transition from traditional water management systems towards a more integrated and sustainable approach known as "One Water" is vital. Although cities are enthusiastic about a One Water paradigm, there is a limited scholarly understanding of how to enable this transition. This study, therefore, aimed to improve intellectual comprehension of the factors that influence One Water transitions based on a series of expert interviews that were conducted with a number of utilities across North America. It was found that achieving social–environmental justice is among the most prominent drivers for utilities to start their transition, followed by concerns about climate change, water quality impairments, groundwater depletion and subsidence, and population growth. Our findings revealed that several critical barriers including a lack of regulatory frameworks and existing institutional siloes impede the transition toward One Water. Additionally, our thematic framework revealed that technological, cultural, and institutional actions are required to enable One Water transitions. However, the frequency of actions in the thematic framework sheds light on the point that cultural, institutional, and regulatory solutions are needed more than technological innovations to support the paradigm shift. Finally, our efforts identified nine key elements of a "One Water City" that could be used to characterize progress towards implementation of One Water approaches. Insights from this paper not only provide water managers with an understanding of the perspectives and actions required for enabling the One Water paradigm shift, but also can be used to develop a framework for self-assessment. [ABSTRACT FROM AUTHOR]

Understanding the knowledge of climate-change impacts on water-resources is a priority. This article goes a step further with the main objective of this study to explore water-practitioners' viewpoints regarding the water supply-side and water demand-side management measures in coping with future climatic impacts to achieve urban water security. Interviews were conducted with water-professionals from regional urban water authorities of Queensland, Australia. From a water-practitioner's viewpoint, surface water is perceived to remain a high-priority water resource for the region, although climate-change is projected to make this resource more vulnerable in the area. Climate-change risks have rarely been considered as a selection-criterion when long-term water solutions were investigated by water-practitioners. Although non-pricing water demand management policies were used to reduce water demand in the region, pricing-based water demand management tools are perceived by the water-professionals to be the most effective at reducing water demand in the study area, if implemented. [ABSTRACT FROM AUTHOR]

Zimbabwe desperately requires financial assistance to fix existing infrastructure and build new urban water systems. This analysis suggests that PPPs may give Zimbabwe the best opportunity to overcome its problems with water infrastructure. Zimbabwe still has trouble supplying water to its cities because of a shortage of resources and deteriorating infrastructure. This situation was already confirmed by the United Nations Children's Fund (UNICEF) (see 2019 reports), and PPPs could mitigate the financial challenges to assist the Zimbabwean Government. The study utilised qualitative research to gather information. Interview responses were supplemented with a literature review to thematically state responses. The results demonstrate that political backing, government accountability, economic viability, and suitable statutory, financial, technological, and institutional frameworks are the key prerequisites for implementing PPPs effectively in Zimbabwe. The study proposes that PPPs are perceived as an alternative reform strategy for improved urban water infrastructure in the country. However, PPPs must consider the implementation imperatives before being adopted and implemented. This requires an environment conducive to operating PPPs, including proper planning and meticulous implementation. If entered hurriedly, PPPs can exacerbate the problems they were implemented to rectify, thereby saving the taxpayers' hard-earned money. [ABSTRACT FROM AUTHOR]

The application of methods using graphs to model a variety of engineering issues has been known for several decades, but the application of graph algorithms to model the urban water management issues is a completely new approach. The article reviews the scientific literature on integrated urban water management systems in terms of the use of graph theory algorithms in this topic. Such a review has not been done before and constitutes a completely novel study. Some of the algorithms presented are directly derived from graph theory, while others were developed from other sciences, including environmental engineering or genetics, to solve specific engineering problems. The paper presents a general scheme and a brief description of the most important components of an integrated urban water management system. The necessary concepts of graphs were defined, the origin and the principle of graph algorithms used in modeling water management issues (Loop-By-Loop Cutting Algorithm, Hanging Gardens Algorithm, Tree Growth Algorithm, Dijkstra’s Algorithm, Genetic Algorithm, and Bayesian Networks Algorithm) were described. Their use in modeling the issues in stormwater, sanitary sewage and water distribution system was described. A complete list of scientific literature in this field was provided.

In this article, I argue that drinking water quality is a sociomaterial phenomenon with scale and temporality; I argue further that the way in which actors in urban environments influence drinking water quality affects how people access water and the degree to which they are exposed to drinking-water–related hazards. Understanding the complexity of the multiple possible impacts on drinking water quality requires attentiveness to the heterogeneous social, political and technical relations that together constitute a 'drinking water quality assemblage'. Different problematisations of drinking water quality can also contribute to the emergence of multiple contested assemblages. Using a qualitative case study developed over eight months in Senegal including interviews, participation, observation and document review, I explore coexisting assemblages of drinking water quality in Kaolack, Senegal. I categorise the assemblages as state, implementer, provider and consumer. These vary in the degree to which each assemblage is flexible or rigid: they also exhibit differences in the scales and temporalities of concern for drinking water quality problems. I argue that this theorisation of drinking water quality relates better to the dynamic and multiple materiality of water and water quality than do the static and inflexible technical definitions that are more commonly found in policy and planning documents.

The search for improved water pricing is central to urban water reform in many countries. Establishing efficient water prices is notoriously difficult, not least because different customers have different demands for water and yet they are presently faced with a one‐size‐fits‐all approach to pricing and service. This is especially challenging where water availability fluctuates widely, as is the case in many parts of Australia, because the impacts of exposure to episodic periods of scarcity can differ markedly. There is now substantial interest in the notion of 'unbundling' the water product to provide a better fit between customers' preferences and the level of service received. Following this trend, this study provides important insights into householders' willingness to pay for a range of flexible water options using a choice experiment. The paper reports a relatively underemployed extension to the latent class modelling framework to investigate preference heterogeneity towards urban water products, including purchasing services that involve the provision of environmental and amenity outcomes. The work adds to studies that use choice data to reveal heterogeneity while improving our understanding of household customers' demands. Overall, it also brings into focus questions about the future management of water in urban contexts. [ABSTRACT FROM AUTHOR]

Water is not only an indispensable part of the natural environment but also an important component and basic guarantee of the urban ecological environment. Total Suspended Matter (TSM) is an important parameter to measure urban water quality. Therefore, it is essential to carry out real-time and efficient monitoring of the total suspended matter of urban water bodies to ensure water quality safety of urban water bodies. In this paper, the inversion model of TSM concentration of urban water is constructed using Unmanned Aerial Vehicle (UAV) multi-spectral images and measured TSM concentration data. The results show that: (1) The NIR band of the UAV image is highly sensitive to TSM concentration. (2) When the sample size is small, it is found that the TSM regression model is more stable and explanatory than the machine learning model. (3) The overall water quality of urban water bodies is poor, especially in areas with intense human activities such as shipping and construction. The TSM concentration in the river reaches is high, and the TSM concentration in the wider river reaches is higher than that in the narrow river channels and Landscape Lakes, and the TSM concentration remains stable in a certain length of river reaches. It can lay a foundation for further realizing real-time and efficient water quality parameter inversion in the future, and also provide an important scientific reference value for other water quality parameter inversion research, and provide theoretical basis and technical support for the scientific management of water ecological environment in urban water bodies. [ABSTRACT FROM AUTHOR]

A new approach for estimating the household water consumption pattern was developed by taking the impact of the COVID-19 pandemic using geographical data. Water consumption data for two years before and a year after the outbreak of the pandemic were analyzed to recognize the consumption pattern on annual and bi-monthly time scales as well as in different spatial classes. Following the recognition of the pattern, the spatiotemporal distribution of household water consumption was estimated based on the discovered connections between consumption and geographical variables. Once a regression relationship between consumption and population density was observed, an idea was developed to investigate the linear equations and their coefficient of parameters in water consumption groups from very low to very high classes using the training data. The coefficients were then adjusted to account for the pandemic's impact on the consumption pattern. Results showed that the highest increases in consumption were 11% for May–July due to the impact of the pandemic while the impact was from decreasing type during lockdowns. A pandemic-induced decline in the mean of consumption was linked to temporary migration by high-income families, whereas the water consumption of others faced an increase. The impact has also increased the slope of the linear relationship between the annual water consumption and population density increased by 3.5%. The proposed model estimated the annual water consumption with the accuracy of %3.77, %1.82, and %1.85 for two years before, one year before and one year after the pandemic, respectively. [ABSTRACT FROM AUTHOR]

Numerous innovative decentralised urban water solutions have been described over many years, yet their application in practice is still not common at all. While many proposed solutions may have some techno-economic advantages over current systems, the real reasons for the slow uptake have more to do with system-wide inertia and technology ‘lock-in’ where existing solutions are preferred for simplicity and familiarity. A key factor is also the inadequate assessments in project decision making processes that should consider all relevant social, environmental and economic benefits and values. This paper highlights some key barriers and how to address them in a more holistic way. It also identifies opportunities where more integrated, hybrid solutions could offer significant benefits over current technologies. It calls on all key partners in this sector to foster broad and strong collaborations, and on water service providers to be empowered to take an inclusive leadership role in creating such innovative solutions that help address our growing challenges driven by rapid urbanisation and climate change.

Microplastics (MPs) and nanoplastics (NPs) are ubiquitous and intractable in urban waters. Compared with MPs, the smaller NPs have shown distinct physicochemical features, such as Brownian motion, higher specific surface area, and stronger interaction with other pollutants. Therefore, the qualitative and quantitative analysis of NPs is more challenging than that of MPs. Moreover, these characteristics endow NPs with significantly different environmental fate, interactions with pollutants, and eco-impacts from those of MPs in urban waters. Herein, we critically analyze the current advances in the difference between MPs and NPs in urban waters. Analytical challenges, fate, interactions with surrounding pollutants, and eco-impacts of MPs and NPs are comparably discussed., The characterizations and fate studies of NPs are more challenging compared to MPs. Furthermore, NPs in most cases exhibit stronger interactions with other pollutants and more adverse eco-impacts on living things than MPs. Subsequently, perspective in this field is proposed to stimulate further size-dependent studies on MPs and NPs. This review would benefit the understanding of the role of NPs in the urban water ecosystem and guide future studies on plastic pollution management.

Rising water prices threaten affordable access to basic water service in the U.S., especially in low-income communities. Faced with unaffordable water bills, households may use less water than is healthy, forgo other essential services, or fall behind on water bill payments, risking water shutoffs. Affordability ratios (ARs), which express water bills as a fraction of income, are the most common measure of water affordability. However, ARs can underestimate unaffordability due to both spatial aggregation bias and their reliance on indirect proxies for ability to pay. New metrics are needed to identify households at risk of water insecurity due to affordability challenges. Here we investigate alternative water affordability metrics that use water bill late payments and debt to track actual payment behavior at the household level. We define metrics that capture the frequency, duration, and severity of water bill delinquency. We apply these metrics to a case study in Santa Cruz, California, using monthly billing data for approximately 40 000 households from 2009 through 2021. We find large variation in delinquency across households and over time, with higher delinquency linked to proxies for low wealth such as lower assessed home value. Census blocks with similar ARs often have distinct patterns of delinquency behavior, suggesting that block-level median affordability estimates may be masking sub-populations facing affordability challenges. These results highlight the benefits of using multiple, household-level metrics to capture the role affordability plays in household water security.

In the face of urban expansion, ensuring sustainable water consumption is paramount. This study aims to develop a domestic water demand forecast model that considers population heterogeneity and the urban area distribution in a city in the Brazilian Semiarid Region. The methodology comprises three main steps: (1) spatial data collection to identify explanatory variables for a future Land Use and Cover (LULC) model; (2) simulation of LULC data for 2030, 2040, and 2050 using the MOLUSCE plugin; and (3) estimation of domestic water demand based on projected urban area expansion and a linear regression model incorporating demographic indicators of household income, residents per household, total population, and gender. The results demonstrated a consistent LULC simulation, indicating an urban expansion of 4 km2 between 2030 and 2050, with reductions of 0.6 km2 in natural formations and 3.4 km2 in farming areas. Using LULC data, the study predicted a 14.21% increase in domestic water consumption in Campina Grande for 2050 compared to 2010, equivalent to an increase of 2,348,424.96 m3. Furthermore, the spatial analysis draws a spatial profile of water consumption among residents, highlighting the areas with the highest per capita consumption. Thus, this research offers a consistent approach to estimating water demand in regions with limited consumption data, providing valuable insights for decision-makers to consider in urban planning.

Many cities have pledged to achieve carbon neutrality. The urban water industry can also contribute its share to a carbon-neutral future. Using a multi-city time-series analysis approach, this study aims to assess the progress and lessons learned from the greenhouse gas (GHG) emissions management of urban water systems in four global cities: Amsterdam, Melbourne, New York City, and Tokyo. These cities are advanced in setting GHG emissions reduction targets and reporting GHG emissions in their water industries. All four cities have reduced the GHG emissions in their water industries, compared with those from more than a decade ago (i.e., the latest three-year moving averages are 13%–32% lower), although the emissions have “rebounded” multiple times over the years. The emissions reductions were mainly due to various engineering opportunities such as solar and mini-hydro power generation, biogas valorization, sludge digestion and incineration optimization, and aeration system optimization. These cities have recognized the many challenges in reaching carbon-neutrality goals, which include fluctuating water demand and rainfall, more carbon-intensive flood-prevention and water-supply strategies, meeting new air and water quality standards, and revising GHG emissions accounting methods. This study has also shown that it is difficult for the water industry to achieve carbon neutrality on its own. A collaborative approach with other sectors is needed when aiming toward the city’s carbon-neutrality goal. Such an approach involves expanding the usual system boundary of the water industry to externally tap into both engineering and non-engineering opportunities.

The perception that urban stormwater policies are non-existent, incomplete, or lacking in aspects that concern the environment and quality of life in cities has become increasingly common. This is partly due to the increased frequency and magnitude of rainfall events resulting from climate change and its economic, social, and environmental consequences. Population concentration and changes in patterns of living, construction, and urbanization contribute to the pollution of water runoff and receiving waters. Thus, quantity and quality problems add up and often require costly solutions, which are then addressed as economic issues. To deal with all these aspects, many of which were previously absent, stormwater public policies require a paradigm shift to break away from institutional inertia and dependence on the previous path. Without the aim of exhausting the subject, this paper discusses the policy aspects that concern stormwater management and the current and desired paradigm shift. HIGHLIGHT Urban stormwater issues are highly complex as they involve many actors, conflicting interests, difficult to predict future trajectories and causes that are fuelled by consequences. Public policies addressing complex issues are the result of decisions reached by consensus, but not unanimity, among stakeholders and, as institutions, are path dependent and decisive for the outcomes to be achieved.;

Canals and canalized rivers form a major part of surface water systems in European delta cities and societal ambitions to use these waters increase. This is the first assessment of how suitability of these waters can improve for three important uses: transportation, thermal energy extraction (TEE) and recreation. We assess suitability with Suitability Indices (SIs) and identify which alterations in the water system are needed to improve SI scores in Amsterdam, The Netherlands, and Ghent, Belgium. The results show spatial variability in suitability scores. Current suitability for transportation is low (SI score = 1) to excellent (SI score = 4), for TEE fair (SI score = 2) to excellent (SI score = 4), and suitability for recreation is low (SI score = 1). Suitability could improve by enlarging specific waterway dimensions, increasing discharge and clarity, and by enhancing microbiological water quality. The same methodology can be applied to optimize designs for new water bodies and for more water uses. [ABSTRACT FROM AUTHOR]

Water supply has been a chronic challenge in Istanbul since its foundation. Authorities have sought alternative methods since the Roman and Byzantine periods. Cisterns, channels and wells surveyed in urban heritage sites in Istanbul provide evidence of rainwater harvesting (RWH) as a working solution in the past. However, RWH systems have only been utilized in contemporary plans and policies very recently, particularly since the climate change crisis entered the political agenda in Turkey. Taking this as a point of departure, this paper investigates the challenges of widespread implementation of RWH systems in Istanbul through a participatory inquiry with water management actors. Challenges and needs are explored through a set of in-depth interviews and participatory workshops with representatives from water management institutions. The findings reveal that current challenges are related to planning and development, legislation and governance, financing, society, infrastructure, installation and operation of systems. The potential solution is the establishment of a governance mechanism that enables collective action among relevant actors. [ABSTRACT FROM AUTHOR]

The rationale of the study was built on the water infrastructure challenges in Zimbabwe and the challenges in government policies and capacity that demand the participation of public-private partnerships (PPPs) in the development of water infrastructure in Zimbabwe. The study adopted the qualitative research approach, and the information is compiled through a literature review. Through conceptual and document analysis of information, the study also recognised that there are challenges in the existing PPP arrangements in Zimbabwe that require improvement for their absolute contribution to the management of water resources in the country. The data generated by this study were used to understand the complexities and contestations in Zimbabwe and enrich the body of knowledge and literature about water-related PPPs. Effective PPPs for improved urban water infrastructure cannot be achieved by chance. Effective PPPs require deliberate efforts and comprehensive reforms. The study, therefore, posits that with an environment conducive to operating PPPs, in addition to proper planning and meticulous implementation, Zimbabwe has a high chance of successfully implementing such partnerships for improved urban water infrastructure. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution is one of the emerging threats to the water and terrestrial environment, forcing a new environmental challenge due to the growing trend of plastic released into the environment. Synthetic and non-synthetic plastic components can be found in rivers, lakes/reservoirs, oceans, mountains, and even remote areas, such as the Arctic and Antarctic ice sheets. MPs' main challenge is identifying, measuring, and evaluating their impacts on environmental behaviors, such as carbon and nutrient cycles, water and wastewater microbiome, and the associated side effects. However, until now, no standardized methodical protocols have been proposed for comparing the results of studies in different environments, especially in urban water and wastewater. This review briefly discusses MPs' sources, fate, and transport in urban waters and explains methodological uncertainty. The effects of MPs on urban water microbiomes, including urban runoff, sewage wastewater, stagnant water in plumbing networks, etc., are also examined in depth. Furthermore, this study highlights the pathway of MPs and their transport vectors to different parts of ecosystems and human life, particularly through mediating microbial communities, antibiotic-resistant genes, and biogeochemical cycles. Overall, we have briefly highlighted the present research gaps, the lack of appropriate policy for evaluating microplastics and their interactions with urban water microbiomes, and possible future initiatives. [ABSTRACT FROM AUTHOR]

Climate change, population growth and urban sprawl have put a strain on water supplies across the world, making it difficult to meet water demand, especially in city regions where more than half of the world's population now reside. Due to the complex urban fabric, conventional techniques should be developed to diagnose water shortage risk (WSR) by engaging crowdsourcing. This study aims to develop a novel approach based on public participation (PP) with a geographic information system coupled with machine learning (ML) in the urban water domain. The approach was used to detect (WSR) in two ways, namely, prediction using ML models directly and using the weighted linear combination (WLC) function in GIS. Five types of ML algorithm, namely, support vector machine (SVM), multilayer perceptron, K-nearest neighbour, random forest and naïve Bayes, were incorporated for this purpose. The Shapley additive explanation model was added to analyse the results. The Water Evolution and Planning system was also used to predict unmet water demand as a relevant criterion, which was aggregated with other criteria. The five algorithms that were used in this work indicated that diagnosing WSR using PP achieved good-to-perfect accuracy. In addition, the findings of the prediction process achieved high accuracy in the two proposed techniques. However, the weights of relevant criteria that were extracted by SVM achieved higher accuracy than the weights of the other four models. Furthermore, the average weights of the five models that were applied in the WLC technique increased the prediction accuracy of WSR. Although the uncertainty ratio was associated with the results, the novel approach interpreted the results clearly, supporting decision makers in the proactive exploration processes of urban WSR, to choose the appropriate alternatives at the right time. [ABSTRACT FROM AUTHOR]

Major cities located in the Colorado River Basin (CRB) rely on incentive‐based policies to address water use and supply reliability challenges, through programs provided by cities themselves, by state and federal agencies, and by NGOs. This review examines water use trends across cities, the phenomena of declining per capita use, and finds that most large cities have adopted municipal rate structures designed to incentivize lower use. A number of urban areas provide incentives to use gray water and effluent for outdoor use and to harvest rainwater. Incentive‐based programs to protect watershed health have become a water supply strategy implemented through programs and partnerships across the CRB. The paper concludes by reviewing the ways that incentive‐based urban water policies are being evaluated, and by providing guidelines for designing and evaluating programs to reduce urban use and protect watersheds that provide urban supplies. [ABSTRACT FROM AUTHOR]