Search Results (37)

Existing wet tropical urban drainage systems often fail to accommodate runoff generated during extreme rainfall. Water-sensitive urban design (WSUD) systems have the potential to retrofit the existing urban drainage system by enhancing infiltration and retention functions. However, studies supporting this assumption were based on temperate or arid climatic conditions, raising questions about its relevance in wet tropical catchments. To answer these questions, in this study a comprehensive modelling study of WSUD effectiveness in a tropical environment was implemented. Engineers Park, a small sub-catchment of 0.27 km² at Saltwater Creek, Cairns, Queensland, Australia was the study site in which the flood mitigation capabilities of grey and WSUD systems under major (1% Annual Exceedance Probability—AEP), moderate (20% AEP), and minor (63.2% AEP) magnitudes of rainfall were evaluated. A detailed one-dimensional (1D) and coupled 1D2D hydrodynamic model in MIKE+ were developed and deployed for this study. The results highlighted that the existing grey infrastructure within the catchment underperformed during major events resulting in high peak flows and overland flow, while minor rainfall events increased channel flow and shifted the location of flooding. However, the integration of WSUD with grey infrastructure reduced peak flow by 0% to 42%, total runoff volume by 0.9% to 46%, and the flood extent ratio to catchment area from 0.3% to 1.1%. Overall, the WSUD integration positively contributed to reduced flooding in this catchment, highlighting its potential applicability in tropical catchments subject to intense rainfall events. However, careful consideration is required before over-generalization of these results, since the study area is small. The results of this study can be used in similar study sites by decision-makers for planning and catchment management purposes, but with careful interpretation. Full article

Rapid population growth and urbanization are transforming natural landscapes into built environments, resulting in increased stormwater runoff, which poses significant challenges for local governments to manage. Water-Sensitive Urban Design (WSUD) techniques have been implemented to enhance urban stormwater quality, but their effectiveness in managing stormwater quantity and quality across different scales remains uncertain. This study examines the capacity of various WSUD approaches to reduce stormwater runoff volume and peak flow rates in a residential allotment transitioning from a single dwelling to a redeveloped condition with two dwellings. The tested techniques included a rainwater tank, infiltration trench, rain garden, vegetated swale, and permeable pavement. For storm events with a 1-in-5-year Annual Recurrence Interval (ARI)—aligning with typical piped drainage design standards—peak flow rates were reduced by 90% in the redeveloped scenario. Smaller storm events, up to a 1-in-1-year ARI, were frequently eliminated, thereby minimizing disturbances to waterways caused by frequent runoff discharges. Among the tested techniques, the combination of a rainwater tank, rain garden, and infiltration trench demonstrated the greatest effectiveness in reducing stormwater runoff volume and peak flow rates despite considerations of life cycle costs. These findings highlight the potential of integrated WSUD techniques in addressing urban stormwater management challenges. Full article

Stormwater treatment systems play an integral part in achieving sustainable urban development. The performance of these systems is likely to be impacted by potential changes in climatic patterns, including precipitation. This project investigates the simulated impacts of climate change on the performance of stormwater treatment systems used as a part of Water-Sensitive Urban Design (WSUD). Townsville and the Gold Coast of Queensland, Australia, were selected for the study to investigate tropical and sub-tropical climates experienced by cities across the globe adjoining sensitive coastal environments such as wetlands and coral reefs. The daily precipitation output projected by Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models was downscaled to pluviograph input into the Model for Urban Improvement Conceptualisation (MUSIC). The treatment performance of bioretention systems and constructed wetlands was variable across both locations, with some models showing little to no change or improvement. Worsening of treatment performance was more prominent in the tropical climate, with numerous models reaching a decline of up to 16%. However, the highest observed reduction from a single model output occurred in the sub-tropical climate location. To make the WSUD treatment system effective under the future climate scenarios, physical modification is necessary to increase the treatment area or depth. Increasing the area in the worst-case scenario could incur a cost increase of 20% to 30% and present challenges due to development constraints. Increasing the depth could be a viable alternative for bioretention systems but is likely impractical for constructed wetlands. Full article

Despite various sustainable urban development frameworks, over the years, inadequate land use patterns and infrastructure have worsened existing problems related to climate disasters such as flooding, heavy precipitation and droughts. Based on a systematic PRISMA literature search and bibliographic analysis, we analyzed statistical data from 44 articles relevant to water-sensitive urban design (WSUD) and flood risk management (FRM) worldwide from 2013 to 2023. We focused on specific selection criteria that focused on settlement typologies and outcomes, indicators and planning approaches to analyze the impact of flooding on urban infrastructure of four different settlement types in 23 case studies, summarized into nine different approaches. The results show that WSUD and FRM have shared sustainability goals but differ in their focus and applicability depending on the settlement type and indicators. In the context of strategic planning for urban sustainability, it can be stated that WSUD has a much stronger focus on integration and future orientation than FRM. Therefore, WSUD seems better suited to be linked to strategic planning for urban sustainability than FRM. Finally, we propose to extend WSUD to “water-sensitive regional design (WSRD)”. This broader framework would integrate regional hydrological, ecological and socioeconomic aspects to address water issues at a larger scale. Full article

Water Sensitive Urban Design (WSUD) has emerged as a vital framework for integrating sustainable water management into urban planning, tackling the increasing challenges posed by urbanization and climate change. WSUD aims to align water systems with natural ecosystems by minimizing runoff, improving water quality, and promoting biodiversity while also offering recreational and aesthetic benefits for urban residents. While the environmental advantages of WSUD are well-established, its social and economic aspects warrant more in-depth exploration. This review analyses the social and economic impacts of WSUD, focusing on its effects on community well-being, property values, infrastructure costs, and public engagement. It also discusses the significance of citizen perceptions, socio-economic equity, and financing mechanisms in the adoption of WSUD. The findings highlight the necessity for interdisciplinary approaches and policy reforms that incorporate social and economic considerations into WSUD planning to ensure long-term success and sustainability. This analysis aims to enhance understanding of how WSUD can contribute to resilient, equitable, and sustainable urban communities. Full article

The summer of 2022 was one of the hottest and driest summers that Germany experienced in the 21st century. Water levels in rivers sank dramatically with many dams and reservoirs running dry; as a result, fields could not be irrigated sufficiently, and even power generation and supply were affected. The impact of abnormally high temperatures for extended periods (heatwaves) is not restricted to nature and the economy but is also a considerable public health burden. Experts worldwide agree that these extreme weather events are being driven by climate change and will increase in intensity and frequency in the future. The adverse impact of these extreme weather events multiplies among dense urban environments, e.g., through heat islands. This calls for cities to take action to heat-proof and water-secure their urban developments. Water-Sensitive Urban Design (WSUD) is one such approach to mitigate the aforementioned challenges by leveraging the urban water ecosystem with special attention to the subject of water reclamation, retention, treatment and distribution. This paper introduces and builds upon a prototype of WSUD that centers around an artificial lake as an integrated water resource management system (IWRMS) fed by treated grey water and storm water obtained from two housing blocks flanking the water reservoir. Based on the specifications of this prototype, indicators of site suitability are derived and applied to identify potential locations for replicable projects in the city of Darmstadt. The results confirm the impact WSUD can have: a total of 22 sites with 2527 apartments are found suitable for prototype implementation in Darmstadt. Savings in town water consumption from these 22 sites would add up to 147 million liters. Further benefits include the provision of 24 million liters of irrigation water, storm water retention, adiabatic cooling during heatwave, increased biodiversity and the improvement in livability of the sites and the city. Full article

Water Sensitive Urban Design (WSUD) technologies are green infrastructures that aim to restore the hydrological balance of urban catchments. This research aimed to investigate the impacts of climate change in an infiltration-based WUSD, called soak-away, at residential allotments from a Village Green townhouse complex, Aldinga, South Australia. To do so, specific rainfall data for the study area were collected and then projected for the years 2030, 2060 and 2090, considering the RCP 4.5 and 8.5 pathways. The projections were determined using CSIRO’s Climate Futures tool, as suggested in the Australia Rainfall Runoff guidelines. The rainfall’s projected impacts on the soak-away performance and dimensions were analyzed in terms of the Village Green catchment conditions, using the MUSIC model and stormwater source control principles. When analyzing the RCP 8.5 pathway for different years, the distinction in soak-away design was more evident and was directly related to the peak flow percentage of the increase obtained in the MUSIC model. On the other hand, for RCP 4.5, the years 2030 and 2060 presented the same characteristics, and 2090 had an equivalent rainfall projection as RCP 8.5 2030. Regarding treatment effectiveness, the soak-away dimensions reached almost 100% of pollutant removal, which indicates that the approach might oversize the system. Nonetheless, when comparing all soak-away designs, the recommended soak-away system tends to be conservative due to the uncertainties surrounding future climate projections. Full article

This study addresses the growing interest in utilizing remote sensing tools for locating sustainable drainage systems (SuDS) in urban environments. SuDS, recognized as Nature-based Solutions (NbS), play a crucial role in enhancing urban resilience against climate change. This study focuses on the calibration process required to establish a correlation between the Topographic Wetness Index (TWI), derived from high-precision digital elevation models (DEMs), and soil moisture (SM) data obtained from satellite imaging. This calibration serves as a method to optimize the placement of sustainable urban drainage system vegetated techniques in urban areas. This study leveraged the exceptional resolution of PAZ satellite radar data to effectively detect variations in SM, particularly in grass-type vegetated land. The sensitivity of the X-band radar signal to moisture levels and changes in ground roughness proved valuable in tracking SM dynamics. The core of the study involved deriving the TWI from a high-resolution digital terrain model (DTM). The correlation between the TWI and SM values demonstrates robustness, with an R² value of 0.77. These findings significantly advance the calibration of TWI values with SM measurements, enhancing their practicality in identifying areas prone to water accumulation. The study’s outcomes provide valuable insights for guiding the strategic placement of SuDS in urban environments, contributing to the effective management of water-related challenges in the face of urbanization and climate change. Full article

Water-sensitive urban design (WSUD) is a subset of nature-based solutions (NbSs) that are implemented worldwide. However, the WSUD guidelines in some local contexts, such as Southeast Asia, remain unclear both for ecological and cultural reasons. This study aims to gather collaborations between researchers, designers, and laypeople in WSUD, which have the potential to be implemented to address water quality issues. The study consisted of three stages: site selection, a design workshop, and public interviews. Utilizing geo-design principles and geographical data, the potential pilot site was identified: a vacant space next to the Tha Phae Gate Plaza. A two-day workshop with landscape design experts yielded six conceptual designs, focusing on diverse themes such as water treatment, plant-based solutions, educational opportunities, and cultural enrichment. Public interviews provided insights into the community’s perspectives on stormwater management, desired amenities, environmental considerations, and governance concerns. The results highlighted a collective interest in using NbSs for stormwater treatment and enhancing the area’s recreational and educational potential. This study offers a comprehensive approach to addressing water quality issues in urban settings while considering local cultural, recreational, and environmental needs. Full article

The development of the stormwater management strategies, e.g., low-impact development (LID), water-sensitive urban design (WSUD), and sustainable drainage solutions (SUDS), was initiated in the mid-1980s as a set of engineering approaches and technologies to reduce the harmful effects of stormwater. Over time, all of them evolved in the holistic, multidisciplinary approaches and, today, they are increasingly viewed and implemented under the umbrella term “Nature-based Solutions” (NbS). The technical elements and measures of these NbS represent various technical solutions, implemented i.a., according to the suitability of the site to achieve their maximum efficiency. Currently, there are no standards or procedures for the application of NbS technologies in Serbia. To overpass this and encourage implementation, we carried out preliminary assessment of NbS elements suitability for application in eight urban settlements in the Region of Southern and Eastern Serbia. The assessment is based on publicly available data and performed according to the existing recommendations in the field of spatial planning and rainwater management for WSUD. The analyses were conducted by GIS tools that involved spatial analyses of various terrain characteristics and provided an insight into the criteria, i.e., constraints that are key to the placement of various technical elements, including bioretention, rain garden, and permeable pavement. Research findings point out that creation of the thematic maps with area suitability ratings for individual NbS stormwater elements might represent a good starting point for further investigation, planning, and design. The proposed framework for preliminary assessment is potentially useful for the countries and regions without regulations in the field of NbS for stormwater management. Full article

Low-enthalpy geothermal systems are a promising source for renewable and clean energy for heating, cooling, and air conditioning residential buildings, contributing to the reduction in greenhouse gas emissions in line with the United Nations’ Sustainable Development Goals. Previous research emerged around the geothermal utilization of Sustainable Drainage Systems (SuDS) as multifunctional surfaces for stormwater control and energy saving, developing the water–energy nexus. However, these studies did not comprehensively considered the energy aspects for SuDS design, using non-standardized tests to measure the main thermal parameters. This research aims to address this gap by proposing a novel hybrid engineering procedure to study the thermal properties of SuDS layers and materials through experimental tests combined with steady-state and transient numerical simulations, using green swales operating under dry and wet conditions as a first case study for SuDS techniques. Novel materials incorporated into dry swales (expanded clay and construction and demolition waste) were tested. The results validated this new methodology, reporting an increase of 87% under dry conditions, and 51% under wet scenarios in the thermal insulation performance in comparison to standard materials. A better thermal performance of the systems can be achieved by approaching SuDS design from a holistic viewpoint that integrates energy aspects. Full article

Several studies highlight the risks related to the growing water crisis, worsened by the effects of pollution, which increasingly make water sources non-potable. The current water-sensitive urban design (WSUD) approach improves resource efficiency and implements urban livability by combining natural water flows with all the scales of the urban landscape. The logistic and operational management of water disposal/treatment and distribution requires performing service design according to cities’ physical and morphological features, starting from their architectural and landscape characteristics. This paper aims to prove that different landscapes can offer different inspirations and possibilities to imagine a WSUD-coherent system, fulfilling the integration requirements with the urban system. For this purpose, three case studies, differing by dimension, morphology, and urban typology, are analyzed, experimenting with circular water usage with no resource waste. This research proposes concrete actions such as conservation, restoration or addition of permeable surfaces, the installation of new accumulation and treatment systems, and the use of water-saving devices. Starting from redesigning the water system, they can also include punctual redevelopment interventions on the urban built environments and opportunities for network development with public administrations, private businesses, third-sector organizations, and end users. This experimentation has led to water savings of up to 80% of the current consumption scenario. Full article

As a result of climate change and urbanization, human activities are placing increasing pressure on nature, including with regard to urban stormwater runoff; consequently, various concepts related to urban stormwater runoff management have been proposed to tackle this problem in multiple countries. In this study, the latest research and techniques related to stormwater runoff management are reviewed in detail. A bibliometric analysis of proposed stormwater runoff management concepts developed from 2001 to 2021 was conducted based on a screening of 1771 studies obtained from the Web of Science (WoS). Bibliometric analysis is a research method that can be used to quantitatively analyze academic literature. Visualization of the data obtained from the literature using CiteSpace software and subsequent analysis of patent data through S-curve prediction were performed. The United States, China, and Australia were the top three countries from which publications on this issue were sourced. Each country tends to study its own most relevant issues and has a particularly clear understanding of its own research landscape. The development of stormwater runoff management concepts was analyzed using reference emergence analysis. This was followed by keyword clustering and keyword emergence analysis to identify current research hotspots, trends, technological developments, and limitations. The limitations and emerging trends related to current stormwater runoff management concepts are discussed thoroughly, and suggestions for future studies are provided. Full article

Green roofs (GR) are known as one of the most effective water-sensitive urban design (WSUD) strategies to deal with numerous environmental and social issues that urbanized cities face today. The overall quality of research on GRs has significantly improved and an increasing trend is observed in the amount of research over the last decade. Among several approaches, the application of modeling tools is observed to be an effective method to simulate and evaluate the performance of GRs. Given that studies on GRs at a catchment scale are limited, this paper aims to provide a simple but effective framework for estimating the catchment-scale impacts of GR on runoff quantity and quality. MUSICX, an Australian-developed software that possesses the advantages of a conceptual model, is chosen as the modeling tool in this study. While MUSICX has built-in meteorological templates for Australian regions, this tool also supports several climate input file formats for application by modelers in other parts of the world. This paper presents two different modeling approaches using the Land Use node and Bioretention node in MUSICX. The steps used for model calibration are also provided in this paper. The modeling results present the annual reductions in runoff volume, total suspended solid (TSS), total phosphate (TP), and total nitrogen (TN) load. The largest reductions of roughly 30% per year were observed in runoff volume and TN load. The annual runoff reduction rate reported in this study is close to that of other published results. Similar research outcomes quantifying the benefits of GRs play a major role in facilitating the widespread implementation of GRs due to the awareness of both positive and negative impacts of GRs. Future studies are recommended to concentrate on modeling the impacts of implementing GRs at a large scale (i.e., scales exceeding the single-building scale) to fill the research gaps and enhance the modeling accuracy. Full article

Extreme rainfall events cause an increase in the flow into aging sewer networks, which can lead to Sanitary Sewer Overflows (SSOs). This literature review presents a complete assessment of the application of Water Sensitive Urban Design (WSUD) approaches as mitigation strategies for reducing rainfall-induced SSOs. The review highlights the various WSUD techniques identified in past studies for reducing sewer overflows. In these studies, it was identified that permeable pavements, green roofs, raingardens/bio-retention cells and rainwater tanks were the most popular WSUD strategies that have been extensively used in the past for the mitigation of sewer overflows. WSUD or “green” approaches also have enormous environmental, social and economic benefits when compared to the conventional “gray” approaches for sewer overflow mitigation. However, there have been limited studies conducted in the past that highlight and quantify the benefits of WSUD approaches for sewer overflow mitigation, particularly when such strategies are applied at a large scale (e.g., city scale). This review has identified the modelling software, SWMM, to be the most widely applied tool that has been used in the literature for WSUD modelling. It was also identified that with climate change-induced extreme rainfall events on the increase, WSUD-based “green” strategies alone may not be enough for the mitigation of sewer overflows. A suitable sewer overflow mitigation strategy could be green or a hybrid green-gray strategy, which would need to be identified based on a detailed context specific analysis. Full article