Urban Water Management Systems Research Articles

Exploring the Statistical and Distributional Properties of Residential Water Demand at Fine Time Scales

Residential water demand consists one of the most uncertain factors posing extra difficulties in the efficient planning and management of urban water systems. Currently, high resolution data from smart meters provide the means for a better understanding and modelling of this variable at a household level and fine temporal scales. Having this in mind, this paper examines the statistical and distributional properties of residential water demand at a 15-minute and hourly scale, which are the temporal scales of interest for the majority of urban water modeling applications. Towards this, we investigate large residential water demand records of different characteristics. The analysis indicates that the studied characteristics of the marginal distribution of water demand vary among households as well as on the basis of different time intervals. Both month-to-month and hour-to-hour analysis reveal that the mean value and the probability of no demand exhibit high variability while the changes in the shape characteristics of the marginal distributions of the nonzero values are significantly less. The investigation of performance of 10 probabilistic models reveals that Gamma and Weibull distributions can be used to adequately describe the nonzero water demand records of different characteristics at both time scales.

Advance of the Method estimating the Benefit of Storm Water Usage in Urban Area

The storm water causes the flood in urban area, and it could be treated as a special water resource in storm water management which could be divided into three development phases. The urban storm water management systems are analysed in this paper. The methods estimating the benefit of storm water management including benefit identification, index system and estimate method are introduced.

Use of Nonlinear Membership Functions and the Water Stress Index for the Environmentally Conscious Management of Urban Water Systems: Application to the City of Morelia

This article proposes a multiobjective optimization strategy based on a fuzzy formulation for the sustainable design and planning of water supply chains in urban areas that considers simultaneously economic and environmental objectives. Harvested rainwater and reclaimed water are considered as alternative sources to reduce freshwater consumption while maximizing water revenues and minimizing land usage. As opposed to other models that attempt to minimize water consumption, this work seeks to minimize the water stress index, which quantifies the impact of freshwater consumption with respect to the specific location where the withdrawals take place. We illustrate the capabilities of this approach through its application to a real case study based on the city of Morelia in Mexico, in which we show that the use of alternative water sources along with an appropriate water distribution plan can reduce the impact over natural reservoirs.

Water quality monitoring in smart city: A pilot project

Abstract A smart city is an urban development vision to integrate multiple information and communication technology (ICT), “Big Data” and Internet of Things (IoT) solutions in a secure fashion to manage a city's assets for sustainability, resilience and liveability. Meanwhile, water quality monitoring has been evolving to the latest wireless sensor network (WSN) based solutions in recent decades. This paper presents a multi-parameter water quality monitoring system of Bristol Floating Harbour which has successfully demonstrated the feasibility of collecting real-time high-frequency water quality data and displayed the real-time data online. The smart city infrastructure – Bristol Is Open was utilised to provide a plug & play platform for the monitoring system. This new system demonstrates how a future smart city can build the environment monitoring system benefited by the wireless network covering the urban area. The system can be further integrated in the urban water management system to achieve improved efficiency.

Situations, challenges and strategies of urban water management in Beijing under rapid urbanization effect

Abstract As the capital and a major political hub for China, Beijing has undergone a rapid urbanization effect with significant population growth in recent years. At the same time, Beijing has also been suffering from severe water problems such as water scarcity, urban flooding and other issues related to water pollution. These have increasingly generated severe water problems and stymied the pace and scope of sustainable urban development. The critical challenges faced by water resource administrations pertains to the issues of sustainable management of water resources and the relevant actions to be put in place in order to address these water-related problems. In this study, the current water situation of Beijing is described in great detail focusing on water resource amounts, water supply, water consumption and water pollution changes analyzed from historical to recent years. The challenges of Beijing urban water management systems are also analyzed to offer possible solutions in light of the current trends. Finally, a number of useful strategies and action-oriented measures are provided for Beijing's urban water resource administration to assist them in overcoming the current water management challenges and for them to move towards a more sustainable developmental city.

Rethinking urban water management in Addis Ababa in the face of climate change: An urgent need to transform from traditional to sustainable system

AbstractUrban water management in Addis Ababa, Ethiopia, is of significant concern to the city government owing to the growing demand for water, poor urban water management practices, insufficient and ineffective infrastructures, and climate change. The objective of this study is to review current water resources and management practices, consider the sustainability of the urban water cycle in relation to climate change, and devise a feasible strategy for a sustainable urban water management system. The results of this study show that the situation as it is now is not sustainable at current levels of demand and supply, either in terms of the systems’ management practices, or in terms of the challenges posed by climate change. An Integrated Urban Water Management strategy that covers the entire urban water cycle, including diversification of water sources, protection and conservation of water, sustainable exploitation, distribution, and consumption and wastewater management, water recycling, nutrient reuse, and safe wastewater disposal, should be implemented as soon as practicable.

Community-based adaptation measures for Water Sensitive Urban Design in context of socio-environmental vulnerability

The paper describes the experimental results of a Water Sensitive Urban Design (WSUD) implementation that tests the holistic approach for an integrated urban water management system as an adaptation measure to cope with climate change in socio-environmental vulnerability conditions. The work is based on a socio-technical perspective for the development of micro-scale water sensitive measures in East Naples (Southern Italy), a deprived multi-risk area where emerging socio-ecological criticalities are calling to formulate adaptive strategies that consider local community claims and embed bottom-up processes. Community-based design actions are proved to be effective for the co-production of resilience practices, including the social capital in climate-resilient transition of the built environment.

Sustainable Measures for Mitigation of Flooding Hazards: A Case Study in Shanghai, China

Global warming induces temperature variations and sea level changes for a long period of time. Many coastal cities around the world have experienced the harmful consequences of sea level changes and temperature variations. The city of Shanghai in China also suffers from the serious consequences of these two climatic factors. The geological and climatic conditions of Shanghai make it sensitive to flooding risks during heavy rainfall events. This paper analyses the conditions of sea level changes, temperature variations, and heavy rainfall events in Shanghai. Correspondingly, eustatic sea level change, tectonic movement of the continent, and land subsidence in Shanghai have effects on sea level changes. Correlation analysis indicates extraordinary short duration rainfall events have a relationship with temperature variations due to global warming. Moreover, the number of extraordinary torrential rainfall events also has a correlation with sea level changes. Pluvial flooding and potential damage to coastal structures are more likely to have serious effects as the number of flooding hazard events due to global warming and sea level changes increases. This study also established that to efficiently protect the environment, control economic losses, and prevent potential hazards, extra countermeasures including monitoring, forecasting, and engineering technology treatment should be adopted. Monitoring measurements combined with a database system on a website was found to be useful for forecasting and simulating flooding hazards. For systematic sustainable urban water system management, appropriate treatment technologies, such as sustainable urban water system, which can control and manage water quantity and quality, namely “the Sponge City”, should also be considered.

Opportunities and challenges of the Sponge City construction related to urban water issues in China

Waterlogging is one of the major water issues in most cities of China and directly restricts their urbanization processes. The construction of Sponge City is an effective approach to solving the urban water issues, particularly for the waterlogging. In this study, both the urban issues emerged at the stage of rapid urbanization in China and the demands as well as problems of Sponge City construction related with the water issues were investigated, and the opportunities and challenges for the Sponge City construction in the future were also proposed. It was found that the current stormwater management focused on the construction of gray infrastructures (e.g., drainage network and water tank) based on the fast discharge idea, which was costly and hard to catch up with the rapid expansion of city and its impervious surface, while green infrastructures (e.g., river, lake and wetland) were ignored. Moreover, the current construction of Sponge City was still limited to low impacted development (LID) approach which was concentrated on source control measures without consideration of the critical functions of surrounding landscapes (i.e., mountain, river, wetland, forest, farmland and lake), while application of the integrated urban water system approach and its supported technologies including municipal engineering, urban hydrology, environmental science, social science and ecoscape were relatively weak and needed to be improved. Besides, the lack of special Sponge City plan and demonstration area was also a considerable problem. In this paper, some perspectives on Good Sponge City Construction were proposed such as the point that idea of urban plan and construction should conform to the integral and systematic view of sustainable urban development. Therefore, both the basic theoretical research and the basic infrastructure construction such as monitoring system, drainage facility and demonstration area should be strengthened, meanwhile, the reformation and innovation in the urban water management system and the education system should also be urgently performed. The study was expected to provide a deeper thinking for the current Sponge City construction in China and to give some of suggestions for the future directions to urban plan and construction, as well as urban hydrology discipline.

Food consumption and related water resources in Nordic cities

Many modern cities have strongly invested in the sustainability of their urban water management system. Nordic cities like Stockholm or Copenhagen are amongst pioneers in investments towards integrated urban water management. However, cities can never be fully self-sufficient due to their dependency on external (water) resources. In this paper, we quantify this water dependency with respect to food consumption in nine cities located in the five Nordic countries (Sweden, Denmark, Finland, Norway and Iceland), by means of the water footprint concept. Detailed urban water footprint assessments are scarce in the literature. By analysing national nutrition surveys, we find that urban food intake behaviour differs from national food intake behaviour. In large Nordic cities people eat generally less potatoes, milk products (without cheese), meat and animal fats and they drink less coffee than outside city borders. On the other hand, they generally eat more vegetables and vegetable oils and they drink more tea and alcoholic beverages. This leads consistently – for the six large Nordic cities Stockholm, Malmö, Copenhagen, Helsinki, Oslo and Reykjavik – to slightly smaller food related urban water footprints (−2 to −6%) than national average values. We also analyse the water footprint for different diets based upon Nordic Nutrition Recommendations (NNR) for these cities. We assessed three healthy diet scenarios: 1) including meat (HEALTHY-MEAT), 2) pesco-vegetarian (HEALTHY-PESCO-VEG) and 3) vegetarian (HEALTHY-VEG). This shows that Nordic urban dwellers 1) eat too many animal products (red meat, milk and milk products) and sugar and drink too much alcohol and 2) they eat not enough vegetables, fruit and products from the group pulses, nuts and oilcrops. Their overall energy and protein intake is too high. A shift to a healthy diet with recommended energy and protein intake reduces the urban WF related to food consumption substantially. A shift to HEALTHY-MEAT results in a reduction of −9 to −24%, for HEALTHY-PESCO-VEG the reduction is −29 to −37%, for HEALTHY-VEG the reduction is −36 to −44%. In other words, Nordic urban dwellers can save a lot of water by shifting to a healthy diet.

Policy options for promoting urban–rural cooperation in water management: a review

As most cities share their water basins with rural areas, an efficient and environmentally sensible urban water management system needs to consider the interplay between urban and rural water uses. This article analyses the three main challenges at this interface: increased competition for water resources (scarcity); flood management (abundance); and freshwater quality conservation (pollution). The merit of potential policy options is discussed from an economics perspective, taking examples from successful experiences in cities around the world. The benefits and challenges arising from enhanced coordination and integration between urban and rural water management are highlighted.

Stream-flow forecasting using extreme learning machines: A case study in a semi-arid region in Iraq

Monthly stream-flow forecasting can yield important information for hydrological applications including sustainable design of rural and urban water management systems, optimization of water resource allocations, water use, pricing and water quality assessment, and agriculture and irrigation operations. The motivation for exploring and developing expert predictive models is an ongoing endeavor for hydrological applications. In this study, the potential of a relatively new data-driven method, namely the extreme learning machine (ELM) method, was explored for forecasting monthly stream-flow discharge rates in the Tigris River, Iraq. The ELM algorithm is a single-layer feedforward neural network (SLFNs) which randomly selects the input weights, hidden layer biases and analytically determines the output weights of the SLFNs. Based on the partial autocorrelation functions of historical stream-flow data, a set of five input combinations with lagged stream-flow values are employed to establish the best forecasting model. A comparative investigation is conducted to evaluate the performance of the ELM compared to other data-driven models: support vector regression (SVR) and generalized regression neural network (GRNN). The forecasting metrics defined as the correlation coefficient (r), Nash-Sutcliffe efficiency (ENS), Willmott’s Index (WI), root-mean-square error (RMSE) and mean absolute error (MAE) computed between the observed and forecasted stream-flow data are employed to assess the ELM model’s effectiveness. The results revealed that the ELM model outperformed the SVR and the GRNN models across a number of statistical measures. In quantitative terms, superiority of ELM over SVR and GRNN models was exhibited by ENS=0.578, 0.378 and 0.144, r=0.799, 0.761 and 0.468 and WI=0.853, 0.802 and 0.689, respectively and the ELM model attained lower RMSE value by approximately 21.3% (relative to SVR) and by approximately 44.7% (relative to GRNN). Based on the findings of this study, several recommendations were suggested for further exploration of the ELM model in hydrological forecasting problems.

Placing ecosystem services at the heart of urban water systems management

Current approaches have failed to deliver a truly integrated management of the different elements of the urban water system, such as freshwater ecosystems, drinking water treatment plants, distribution networks, sewer systems and wastewater treatment plants. Because the different parts of urban water have not been well integrated, poor decisions have been made for society in general, leading to the misuse of water resources, the degradation of freshwater ecosystems and increased overall treatment costs. Some attempts to solve environmental issues have adopted the ecosystem services concept in a more integrated approach, however this has rarely strayed far away from pure policy, and has made little impact in on-the-ground operational matters. Here, we present an improved decision-making framework to integrate the management of urban water systems. This framework uses the ecosystem service concept in a practical way to make a better use of both financial and water resources, while continuing to preserve the environment.

Sustainable Urban Water System Transitions Through Management Reforms in Ghana

Despite decades of water reforms, Ghana’s struggle to achieve sustainable urban water system is deepened by complex interactions of multi-layered political, socio-economic and managerial characteristics, leaving a rationing system of water supply in major cities like Accra. Using a multi-level perspective framework, the paper examines the dynamics of urban water system transition through management reforms. The study showed how external pressure at the landscape level influenced policy direction within urban water regime through the implementation of neo-liberal economic policies, paving way for resistance and grassroots innovation at the niche level. The implementation of such policies in the reform process did little to help achieve the desired sustainable urban water system goals. The paper suggests a blend of public and private financing with support for grassroots to improve urban water system management. However, subsequent urban water policy reforms must be informed by knowledge of social, economic, and political realities rather than imported generic “best policies and practices” that often conflict with local realities.

Analysis of Changes in Precipitation and Extremes Events in Ho Chi Minh City, Vietnam

Precipitation is one of the most important climate variables which can impact the urban water and urban flooding. Thus, knowledge of precipitation and precipitation extremes is important to manage urban water and to design urban drainage infrastructure to reduce the urban flooding. This paper presented trends in precipitation and precipitation extremes in Ho Chi Minh City for the 1980-2013 period based on the precipitation data obtained from nine rain gauges. Non-parametric test, i.e. Mann-Kendall test, was used for trend analysis, and the precipitation extremes indices were used to calculate the extreme events. The results indicated that the precipitation has increasing trend in the northwest part of the city and decreasing trend in the southeast part of the city in the 1980-2013 period. In addition, the precipitation and precipitation extremes had generally increasing trends. The results obtained in this study can be used for urban water management and sustainable urban drainage system in Ho Chi Minh City.

Urban Water Resources Toolbox - Integrating Groundwater into Urban Water Management

Holistic but applicable approaches are urgently needed to help plan long-term, cost-effective and sustainable urban water management systems. Groundwater is a central element in the urban water cycle of all cities located on aquifers, yet it remains inadequately integrated into urban water management practices. This book describes holistic approaches for quantification and balancing of urban water and solute fluxes that have been developed by the joint Euro-Australian research project AISUWRS. The new tools comprise a chain of interconnected models that link urban water supply, urban drainage and urban groundwater resources. These include a new sewer exfiltration, model that is based on pipe asset conditions which permits flows to the environment to be estimated. The book provides details on the further processing of this information through the unsaturated zone down to aquifer, where numerical groundwater flow and transport models are applied. Concise documentation is provided on each of the models. The practicability of applying the chain of models was tested by applying it in four case study cities in Australia, Germany, Slovenia and the United Kingdom that have diverse conditions in terms of hydrogeologic setup, climate and data availability. This permitted additional validation by field investigations, including problem-oriented monitoring campaigns aimed at assessing the impact of wastewater practice on groundwater. The book provides guidance and examples of the application of multilevel piezometers, on adapted monitoring strategies, and the use for interpretation purposes of microbiological parameters, pharmaceutical residues and related marker species. The socio-economic analysis in the case study cities sometimes uncovered distinctively different problem perceptions and priorities, both in the groups of experts responsible for the water management and with the remaining stakeholders. The AISUWRS project has developed tools to foster these urgently required deliberation processes. Methodologies for formal sustainability assessment with a triple bottom line background were also elaborated and tested during the case studies. The case studies have shown that the approach is valid and constitutes an important step towards integrated urban water management This title belongs to European Water Research Series ISBN: 9781843391388 (Print) ISBN: 9781780402437 (eBook)

Transitioning to sustainable urban water management systems: how to define expected service functions?

Sustainable water management is a worldwide challenge for the twenty-first century. It involves replacing traditional management approaches with a new concept, often referred to as sustainable urban water management (SUWM). This paradigm shift means that SUWM systems must include new services, some of which have already emerged. However, no publications have presented the expected SUWM system in terms of the full range of services it would need to include, and no publications have proposed a method for identifying the services the system must provide. This paper proposes a method for identifying these services and presents a generic petal diagram to represent the service functions of the SUWM system. Moreover, this paper presents a new method for defining these services in a specific territory. This method is based on the confrontation between a general representation and the objectives of the stakeholders in a given system in a given territory. The method is illustrated with a full-scale case study on the Doua eco-campus (Lyon University). This method is intended to aid practitioners to manage its system and to transition to SUWM. It is designed to improve the transparency of decision formulation and to involve stakeholders in the process.

Sustainable Water Management in Urban, Agricultural, and Natural Systems

Sustainable water management (SWM) requires allocating between competing water sector demands, and balancing the financial and social resources required to support necessary water systems. The objective of this review is to assess SWM in three sectors: urban, agricultural, and natural systems. This review explores the following questions: (1) How is SWM defined and evaluated? (2) What are the challenges associated with sustainable development in each sector? (3) What are the areas of greatest potential improvement in urban and agricultural water management systems? And (4) What role does country development status have in SWM practices? The methods for evaluating water management practices range from relatively simple indicator methods to integration of multiple models, depending on the complexity of the problem and resources of the investigators. The two key findings and recommendations for meeting SWM objectives are: (1) all forms of water must be considered usable, and reusable, water resources; and (2) increasing agricultural crop water production represents the largest opportunity for reducing total water consumption, and will be required to meet global food security needs. The level of regional development should not dictate sustainability objectives, however local infrastructure conditions and financial capabilities should inform the details of water system design and evaluation.

Assessing material flows in urban systems: an approach to maximize the use of incomplete data sets.

Data scarcity and uncertainty are the main limiting factors for an integral evaluation of the urban water and wastewater management system (WWMS) in developing countries. The present research shows an approach to use incomplete data sets to analyse the flows of water and nitrogen and to make an integral evaluation of the WWMS at a case study city. By means of data validation and model adaptations the use of literature values is kept at the minimum possible and so the current trends for water consumption and pollution in the city are identified. The material flows were calculated as central values with a certain confidence range and met the selected plausibility criteria. Thus, the first essential step needed to identify the challenges and opportunities of future improvement strategies at the WWMS of the city was possible.

An ecohydrologic model for a shallow groundwater urban environment.

The urban environment is a patchwork of natural and artificial surfaces that results in complex interactions with and impacts to natural hydrologic cycles. Evapotranspiration is a major hydrologic flow that is often altered through urbanization, although the mechanisms of change are sometimes difficult to tease out due to difficulty in effectively simulating soil-plant-atmosphere interactions. This paper introduces a simplified yet realistic model that is a combination of existing surface runoff and ecohydrology models designed to increase the quantitative understanding of complex urban hydrologic processes. Results demonstrate that the model is capable of simulating the long-term variability of major hydrologic fluxes as a function of impervious surface, temperature, water table elevation, canopy interception, soil characteristics, precipitation and complex mechanisms of plant water uptake. These understandings have potential implications for holistic urban water system management.