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There is an urgent need for urban environments to be flood resilient due to increasing urbanization and climate change. This can be addressed by adopting sustainable drainage solutions (SuDS) in households. However, lack of knowledge and awareness among urban residents is a barrier. In this paper, we present an educational serious game called SuDSbury to overcome this barrier and a pre-/post-game survey-based evaluation to study whether the game can educate citizens (and to what degree). An exploratory study with 14 players across three game sessions suggests that playing SuDSbury induced changes in knowledge, comprehension, and personal norms regarding SuDS. However, comprehension of concepts related to urban drainage can be improved by increasing game realism. The game should be further tested with a larger sample and a diverse demographic of urban residents. The participants further found that SuDSbury is fun and engaging to play, making it suitable for broader public interventions. [ABSTRACT FROM AUTHOR]

Cities and towns have developed stormwater systems to remove the runoff from developed areas. Although the systems are efficient in mitigating local drainage issues, they transfer pollutants and sediment to receiving waters, increase the flashiness of the flow regime and reduce ecological health. Water Sensitive Urban Design (WSUD) approaches are now being adopted to mitigate urbanisation and climate change impacts. This paper reports on the result of reviewing more than 200 papers leading to the conclusion that further investigation is vital to understand how WSUD systems can mitigate climate change impacts and rapid urban development due to the population growth and ongoing shift in populations to cities. Further, the importance of understanding the role of WSUD in increasing the liveability of urban areas. The paper also identifies both strengths and limitations of WSUD which is vital to promote realistic expectations and consequently appropriate designs, budgets, and maintenance regimes. [ABSTRACT FROM AUTHOR]

New York City's coastlines are a mosaic of natural and man-made habitats intermixed with housing and industry, all of which are extremely vulnerable to flooding, storm surge, and damaging wave action. Risks are projected to increase over time as sea levels rise, population grows, and the frequency and severity of extreme events increase. This paper investigates the potential role of green infrastructure (GI) as a risk reduction measure, using Hurricane Sandy as a case study. Specifically, this research examines whether the type, size, and configuration of GI played a role in determining the odds of building damages. Results suggest that proximity to different GI types did affect the odds of damage, both positively and negatively, and that the impacts of both small-scale and large-scale natural features varied geographically. Results suggest that nature-based solutions to coastal flooding must be tailored to specific local conditions in order to be effective. [ABSTRACT FROM AUTHOR]

Flooding can cause major disruptions in cities, and lead to significant impacts on people, the economy and on the environment. These impacts may be exacerbated by climate and socio-economic changes. Resilience thinking has become an important way for city planners and decision makers to manage flood risks. Despite different definitions of resilience, a consistent theme is that flood resilient cities are impacted less by extreme flood events. Therefore, flood risk professionals and planners need to understand flood impacts to build flood resilient cities. This paper presents a state-of-the-art literature review on flood impact assessment in urban areas, detailing their application, and their limitations. It describes both techniques for dealing with individual categories of impacts, as well as methodologies for integrating them. The paper will also identify future avenues for progress in improving the techniques. [ABSTRACT FROM AUTHOR]

Stormwater management essentially aims at controlling the surface runoff to reduce water pollution and restore ecosystem integrity. This paper reviews and discusses several optimization problems associated with this field. Different features of such problems were identified to provide a classified investigation of the literature in terms of control approach, performance criteria, stormwater management approach, and uncertainty consideration. Having evaluated the relevant literature based on these factors, the knowledge gaps were extracted. We have noticed that there is an upward trend towards sustainable management of stormwater systems to deal with climate change. Despite this progress, there are still many areas to further develop stormwater management models, many of which relate to uncertainty identification, system-level real-time control, and the proper formulation of multi-objective optimization models. Hence, integration of different criteria in optimization models, and also the study of design vs. operation of stormwater management systems are proposed as further studies. [ABSTRACT FROM AUTHOR]

Disaster management for urban areas is a growing priority owing to factors such as the relentless migration to cities, unplanned development, changing climate, and increasing operational and maintenance costs. New information and communication technologies offer improved opportunities to address these factors. This paper presents and describes the digital city concept as a means of capturing, analysing and applying (digital) information about the city area, its services, and their design and operation. In particular, the functionality of the digital city can be adapted for managing urban flood disasters. The paper highlights the need to manage the urban stormwater cycle integrated with urban planning. Urban flooding should be mitigated by having a judicious mix of both structural and nonstructural strategies, which are selected with the full participation of all stakeholders. The management of urban flooding is illustrated with application to the tropical island of St Maarten. [ABSTRACT FROM AUTHOR]

Frequent water stress episodes affecting urban hubs have caused a shift in urban water management towards integrated approaches and motivated a search for alternative water resources. Large-scale rainwater harvesting on the municipal scale can overcome the disadvantages of climate dependence and the volume restrictions associated with small-scale collection facilities. In this paper, two tools based on the urban metabolism concept are used to determine the water self-sufficiency potential of urban systems from urban runoff: a simple water self-sufficiency potential indicator and a socioeconomic water flow accounting scheme, which includes water losses. Both tools are applied to a densely populated coastal area that exemplifies urban centres in the Mediterranean. This approach is useful for regions with restricted data availability on water use and facilitates information dissemination to policy makers. The results indicate a significant water self-sufficiency potential for the area of study, even under projections of reduced precipitation in the area. [ABSTRACT FROM PUBLISHER]

Changes in precipitation patterns associated with climate change may pose significant challenges for storm water management systems across the U.S. In particular, adapting these systems to more intense rainfall events will require significant investment, though no method currently exists for estimating the costs of these investments on a national scale. To support assessment of these costs at the national level, this paper presents a reduced-form approach for estimating changes in normalized flood depth (the volume of node flooding normalized by the area of the catchment) and the associated costs of flood prevention. This reduced form approach is calibrated to results generated by the U.S. Environmental Protection Agency's Storm Water Management Model (SWMM) for city-wide or neighborhood-level catchments in seven cities across the U.S. Estimates derived from this approach represent a reasonable approximation of storm water management adaptation costs and exhibit no systematic bias relative to results derived from SWMM. [ABSTRACT FROM AUTHOR]

In this paper we describe the execution of a risk-based analysis on a simple, small-scale water resources planning problem. We aim to understand whether a risk-based approach could underpin the regulated water resources planning process in England and Wales. We demonstrate the practical feasibility of the approach and identify clear benefits over the conventional planning methods. We also identify several nontrivial challenges for scaling up and caution against the view that better quality decisions would emerge naturally from risk-based analyses. Useful future research might focus on: (1) the development of practical methodologies for applying these approaches to larger, more complex resource zones; (2) identifying and overcoming problems associated with regulating a risk-based water resources planning process; and (3) developing methods of economic options appraisal that can deploy the outputs of a risk-based analysis to inform planning decisions. [ABSTRACT FROM AUTHOR]

Global flood management is a major issue for most cities which have to deal with worsening factors such as climate change and fast urban growth. Computer models have been used to model and understand urban flooding on a local scale in cities (25–50 km2). It has been practically impossible to model bigger cities in one go in sufficiently high resolution due to the heavy computations involved. The present paper describes a new modelling approach for urban flooding which allows modelling on large city scale (1000 km2) while keeping sufficient resolution, e.g. 5 m or 10 m grid. The multicell approach is applied for the city of Beijing for July 21st, 2012 flood event. Model results are compared to testimonials from the 2012 event. Comparison to traditional 2D urban flood computations shows that the multicell approach is much faster than standard detailed models while keeping a suitable level of precision. [ABSTRACT FROM AUTHOR]

Guidance on what type of rainfall to use when assessing hydraulic capacity of urban drainage systems under climate change is unclear; focus is mainly on what climate factors to use. Based on a case study in Kalmar, Sweden, this paper compares system performance using two design rainfalls, Block rainfalls and Chicago Design Storm (CDS), and selected observed rainfalls, with two methods of addressing future climate: a constant factor and Delta Change (DC) factors that depend on rainfall intensity. The use of CDS rainfalls presents the maximum hydraulic response, whereas Block rainfalls give lower responses but identify critical durations in the system, which may be useful addressing adaptation actions. Observed rainfalls of target return periods gave similar responses to CDS rainfalls, and can be applied with DC factors to address future changes in both intensity and volume. Differences between the two methods indicate a high dependence related to the maximum factors applied on the rainfalls. [ABSTRACT FROM AUTHOR]

Climate change and human activities have changed a number of characteristics of river flow in the northwest of China. Numerous problems such as water resource shortage, drying up of rivers, water pollution are the direct consequences of these changes. In this paper, we used the example of Yulin city in northwest China to assess the spatio-temporal characteristics and driving forces of annual river flow changes. Our research was based on the long-term time series of hydrological data from 1956 to 2005, to analyse annual flow in four main rivers (Kuye River, Tuwei River, Wuding River and Jialu River). The river flow depends upon the runoff characteristics of the river catchment, therefore we used variation ratio, variation index, unevenness, Runoff-Concentration Degree (RCD) and Runoff-Concentration Period (RCP) to determine the change in runoff characteristics of the four main rivers flows of the Yulin city. We tested the tendency of runoff by the Mann-Kendall non-parameter statistical method to obtain the temporal evolution law. At the same time, Kriging spatial interpolation and GIS were used to derive the spatial evolution law. The dates of climate change (precipitation) and human activities were also used to calculate the driving forces for annual runoff changes of the rivers’ catchments. Through the accumulation curves and multi-recursive techniques, we built the correlation between precipitation and runoff. The driving factors for annual runoff change were then calculated by using the runoff coefficient method. Results showed that the distribution of annual runoff was uneven and had a small accumulation in July and August, especially in Kuye River, and there seemed to be a significant reducing trend in annual runoff. Isolines and the thematic map of Mann-Kendall tests U(R) revealed that the Tuwei River's catchment is the most affected catchment, with annual runoff substantially changed. At the 5% significance level, precipitation did not significantly drop compared with annual runoff. We also found that precipitation is not the only factor responsible for the decreased annual runoff. Therefore we included human activities affect in this case study by using the past 25 years land use, water conservancy and urbanisation data. We discriminated the impacts of climate change and human activities on the surface runoff by multi-recursive analysis method and runoff coefficient method. The results showed that human activities are the direct cause for the changes of river runoff. The results of the study also revealed that the Wuding and Jialu rivers had the most and the least changes in the runoff respectively; this phenomenon should be seriously considered for future water resources planning and management. [ABSTRACT FROM PUBLISHER]

The need for efficient water resources management is currently more pressing than ever, considering population growth and increased reliability requirements, under climate change conditions. On average, one-third of the total water abstracted for urban uses is being lost due to leaks and breaks occurring in water distribution networks. This means that significant amounts of water and revenues are being lost, forcing water utilities to consider developing effective water loss and Non-Revenue Water reduction strategies. Additionally, all water utilities operating in EU countries should, by the end of 2010, develop and implement appropriate water pricing policies that will guarantee the recovery of the full cost of the water being used. This strict obligation makes the reduction of water losses an even more urgent goal that the water utilities have to achieve. The first step towards all the above-mentioned goals is to safely evaluate the performance level of the water network. Thus, the IWA Task Forces on Water Losses and Performance Indicators (PIs) developed specific tools (e.g., the standard international water balance and various PIs), to help water utilities use a common language that will assist know-how and experience exchange through an effective benchmarking process. The paper presents the results of using the above-mentioned IWA tools, in the case of the Larisa city water distribution network in Greece. This is the first time that such an attempt has taken place in Greece. During this process, the problems faced and the ways to tackle them are analyzed, focusing on the role of key factors that had to do with local conditions. Larisa's results are compared to data available from similar cases. Sensitivity analysis was used to check the impact of the variables' uncertainty to the results. Finally, water loss reduction measures are proposed towards an effective pressure management strategy and a proactive pipe maintenance policy based on safely estimating the pipes' optimum replacement time. [ABSTRACT FROM AUTHOR]

Norway has frequently encountered flood damage in urban areas during recent years. In this paper the authors, taking Veumdalen catchment in Fredrikstad as an example, simulated the possible consequences in the sewer system, in the present, predicted and artificial climate scenarios. Indicators that describe (1) surface flooding, (2) surcharging sewers, (3) basement flooding and (4) combined sewer overflow (CSO) are defined to represent the adverse effects of climate change. It is concluded from the annual-based simulation that the total volume of water spilling from the flooding manholes will increase 2-4-times the increase in precipitation, and the total CSO will increase 1.5-3-times as much as the increase in precipitation. The simulation results also show that the number of flooding manholes and number of surcharging sewers may change dramatically and irregularly with a slight change of precipitation, and vary with events and durations. [ABSTRACT FROM AUTHOR]