City Stormwater Research Articles

Exploring public attitudes toward implementing green infrastructure for sponge city stormwater management

Sponge city stormwater management (SCSM) strategy in China aims for sustainable stormwater handling. While many studies have examined the technical aspects of sponge city green infrastructure (SCGI), few have explored public perspectives. This study sought to understand public perceptions, the perceived value of SCGI’s ecosystem service benefits, and the potential for diverse financial compensation methods in sponge city construction. A survey conducted in five Northeastern Chinese cities, involving 1,534 participants, was analyzed using descriptive statistics and logistic regression. The findings reveal no significant correlation between socio-demographic factors and understanding of stormwater management, indicating the concept’s broad accessibility. Public valuation of ecosystem services showed clear priorities, and factors like homeownership and flood experiences significantly impacted the valuation of specific services. Moreover, the study identified a generally positive public attitude towards investing in SCSM, particularly through stormwater fees, underscoring the viability of diverse funding mechanisms. These insights are pivotal for policymakers and urban planners in formulating sustainable and resilient urban water management strategies.

Application of artificial intelligence in digital twin models for stormwater infrastructure systems in smart cities

Digital twins provide insights into physical objects by serving as advanced virtual representations. Their sensors capture detailed information about an object’s functionality through their use of various sensors. It is possible to gain a deep understanding of the object’s performance and potential areas for improvement by collecting data, which includes metrics such as energy output, temperature, and weather conditions. Digital twins are becoming important in a variety of research and industrial application sectors as production lines and processes become more digitalized and as improved data analysis techniques such as machine learning and enhanced visualization techniques are used. There is no unified definition of the digital twin concept in scientific literature, which results in imprecise applications and the weakening of its terminology. However, this study demonstrates how digital twin models can be applied to urban drainage systems. As a result, this highlights the relatively novel use of digital twins within the field of urban water system engineering. Our review of the language, practices, and directions in smart stormwater management provides a framework to organize and comprehend the current research landscape while highlighting crucial areas for future research. Our results demonstrate that there is near-unanimous agreement within the literature that smart technology has been, or will be, advantageous for stormwater management. However, while some progress has been made in terms of quantity management, maturity in water quality management has not yet been achieved. This study examines the scientific literature on digital twins in the application of artificial intelligence for smart city stormwater infrastructure systems, specifically focusing on urban drainage systems. A demonstration of the workflow and features of current digital twin applications in urban drainage systems is also presented, providing valuable insights and guidance for future research and development in this field.

Stormwater Infrastructure Resilience Assessment against Seismic Hazard Using Bayesian Belief Network.

Resilient stormwater infrastructure is one of the fundamental components of resilient and sustainable cities. For this, the resilience assessment of stormwater infrastructure against earthquake hazards is crucial for municipal authorities. The objective of this study is to develop a resilience assessment framework for stormwater pipe infrastructure against seismic hazards. A Bayesian belief network (BBN)-based stormwater infrastructure resilience model is constructed based on the published literature and expert knowledge. The developed framework is implemented in the city of Regina, Canada, to assess the city's stormwater pipe infrastructure resilience. The outcome of the model indicates that proposed BBN-based stormwater infrastructure resilience model can effectively quantify uncertainties and handle the nonlinear relationships between several reliability and recovery factors. The model is also capable of identifying the most sensitive and vulnerable stormwater pipes within the network.

Constructing an inventory for fast screening of hydraulic and hydrologic performance of stormwater control measures

Abstract Stormwater control measures (SCMs) are effective and sustainable complementary means of managing stormwater in cities. Unlike underground drainage systems, they require space on the city surface, and therefore must be included in initial sketches of urban planning and design. These initial sketches are often made by architects and urban planners, who are usually not trained in hydrology, and therefore require simple and robust tools to inform their initial plans with respect to stormwater management. There may be local guidelines for dimensioning SCMs, but their applicability is often limited with regard to the range of SCMs, and the methodology behind them may be oversimplified, including a lack of assessment of benefits on the urban hydrological cycle. We developed a methodology for estimating multiple performance indicators of a wide range of SCMs and applied it to Danish meteorological conditions. The methodology includes consulting expected end users, configuring an SWMM model for each SCM type and choosing applicable parameter ranges, running multiple simulations for each type covering the parameter space, and post-processing the results using python and PySWMM. The outputs can be used to draw general recommendations regarding effective application ranges for different SCMs, and to quickly assess the performance of case-specific configurations.

Ranking of general circulation models for Surat City by using a hybrid approach

Abstract Climate change is expected to worsen flood risks by increasing precipitation in and around Surat City. Thus, to study the effect of climate change on Surat City's stormwater drainage network, ranking of general circulation models (GCMs) and generation of future annual maximum rainfall series is needed, which has not been performed by any reviewed study and is performed in the present study by using a hybrid approach. The ‘hybrid approach’ refers to the combination of past performance approach used for ranking of GCMs and envelope approach based on future climate projections. To rank 21 GCMs belonging to Coupled Model Intercomparison Project Phase 5, a past performance approach is employed by using four performance indicators, which are evaluated on the basis of Surat's simulated and observed monthly rainfall data corresponding to the period 1969–2005. By using an entropy method, weights are assigned to different performance indicators and then ranking of GCMs is performed by employing the TOPSIS method. The top five ranked GCMs are used to generate future annual maximum rainfall series by employing the Reliability Ensemble Averaging method corresponding to Representative Concentration Pathways scenarios 4.5 and 8.5. This study will be helpful for future climate and hydrologic studies to be performed in the study area.

Case study: Diagnosing China's prevailing urban flooding—Causes, challenges, and solutions

AbstractAccompanying its rapid urban development, prevalent urban flooding incidents have been occurring in China in the past two decades with increasing frequency. Through a comparison with generally accepted urban flooding management practices, we (the authors) identified that a lack of surface water runoff management considerations (i.e., missing a major drainage system in urban stormwater system) and inadequate local mitigation are the primary causes of urban flooding problems in China, which in turn is rooted in the planning stage of a city's development. Following identification of the primary causes for the problems, we propose the development of master drainage plans (MDPs) for the concerned cities or regions as the first effective step to mitigate the serious urban flooding problems facing many cities today. An MDP would provide necessary elements to develop a major drainage system for the city's stormwater system and allow for an accurate calculation of parameters necessary for installation of adequate local mitigations. Lessons learned in this study should be useful for China's administrative agencies and professionals while they try to find solutions to their urban flooding problems and beneficial to other nations facing rapid urban development in the future or with existing urban flooding threats.

Infilling missing data of binary geophysical fields using scale invariant properties through an application to imperviousness in urban areas

ABSTRACT High-resolution modelling is needed to improve the understanding and management of storm water in cities. It requires data, which is not always available; hence the growing importance of handling missing data. Here, we use impervious areas in cities as case study. They are responsible for rapid runoff that can generate surface flooding. A methodology to handle such binary missing data relying on scale-invariant properties is presented. It uses a previous study, which showed in 10 peri-urban areas that imperviousness exhibits scale-invariant features from metres to kilometres, to generate realistic scenarios for the missing impervious data. More precisely, fractal fields are commonly simulated thanks to a simple binary multiplicative cascade process (β-model). Here we condition it to the available data. Numerical simulations are used to confirm theoretical expectations. They are then implemented to infill missing impervious data on a 3 km2 catchment and the corresponding uncertainty is quantified.

Combined Approaches to Predict Microplastic Emissions Within an Urbanized Estuary (Warnow, Southwestern Baltic Sea)

Microplastic river emissions are known to be one of the major sources for marine microplastic pollution. Especially urbanized estuaries localized at the land-sea interface and subjected to microplastic emissions from various sources exhibit a high microplastic discharge potential to adjacent coasts. To adapt effective measures against microplastic emissions a more detailed knowledge on the importance of various microplastic sources is necessary. As field data is scarce we combined different approaches to assess microplastic emissions into the Warnow estuary, southwestern Baltic Sea. Resulting microplastic emission estimates are based on in-situ measurements for the catchment emissions, whereas for the remaining microplastic sources within the estuary literature data on microplastic abundances, and various parameters were used (e.g. demographical, hydrological, geographical). The evaluation of the different emission scenarios revealed that the majority of microplastic is likely discharged by the Warnow river catchment (49.4%) and the separated city stormwater system (43.1%) into the estuary, followed by combined sewer discharges (6.1%). Wastewater treatment plant emissions exhibit the lowest percentage (1.4%). Our approach to estimate anti-fouling paint particles emissions from leisure and commercial shipping activities was associated with highest uncertainties. However, our results indicate the importance of this source highlighting the necessity for future research on the topic. Based on our assumptions for microplastic retention within the estuary, we estimate a potential annual emission of 152–291 billion microplastics (majority within the size class 10–100 µm) to the Baltic Sea. Considering all uncertainties of the different applied approaches, we could assess the importance of various microplastic sources which can be used by authorities to prioritize and establish emission reduction measures. Additionally, the study provides parameters for microplastic emission estimates that can be transferred from our model system to other urbanized Baltic estuaries.

Stormwater management of biochar-amended green roofs: peak flow and hydraulic parameters using combined experimental and numerical investigation

Green roofs have been suggested as one solution to manage stormwater in cities. Soil amendments such as biochar appear to be very promising owing to its water retention capacity. Furthermore, biochar is more stable with time (expected half-life over 100 years) than other biomass (fibers), which is likely to degrade at higher rate upon microbial action. Rational utilization of biochar-amended soil in substrates is the critical factor for improving ability of stormwater management (peak-flow reduction and delay). The objective of this study is to evaluate the hydraulic performance of green roofs amended with biochar. Laboratory experiments combined with numerical approach were adopted to achieve the objective. A dual-layer substrate mode with biochar-amended soil was proposed for optimizing the ability of stormwater management. Four experimental columns were built to observe the hydraulic processes under artificial rainfall. Unsaturated hydraulic parameters of substrates were estimated by the inverse solution method. Numerical simulations have been conducted to explore the stormwater management of dual-layer substrates with biochar. Both biochar and vegetation are found to enhance saturated water content. However, their effects on hydraulic properties of soil were opposite, with vegetation having positive influence. Different biochar application modes showed varied performance in peak-outflow delay and reduction. In the selected rainstorm case, the substrate with 3 cm vegetated natural soil in upper layer and 12 cm biochar-amended soil showed a longer delay, higher reduction in peak outflow, and rainwater retention. The dual-layer substrate mode is a flexible utilization of biochar in green roofs. It provided a more reasonable design with the consideration of the local rainfall statistical data.

A Case Study of the Retention Efficiency of a Traditional and Innovative Drainage System

To determine the effectiveness of the retention capacity utilization of traditional and innovative drainage systems equipped with damming partitions, the detailed model tests were carried out. The research results allowed indicating what values of the hydraulic parameter of the innovative drainage system should be adopted in order to effectively use the retention capacity of drainage collectors. The adoption of short distances between the LKR damming partitions and a high level of permissible rainfall of stormwater Hper turned out to be the most effective solution. In the most favorable conditions, the peak flow was reduced by up to 60% (717.46 dm3/s) compared to the values established in the traditional drainage system (1807.62 dm3/s). The benefits obtained resulted from the increased retention efficiency of the drainage system after equipping it with the damming partitions. It was found that the innovative system always achieved the maximum retention capacity with longer rainfall compared to the traditional system. In the real catchment area, an increase in the use of the retention capacity of the drainage system, from an initial value of 65% for a traditional system to almost 88% for an innovative system, was also found. Very large variability of the volume of accumulated stormwater in the conduits of the traditional and innovative drainage system was observed during rainfall, which generated the peak rainfall discharge in the innovative system. With rainfall of TRK duration, the innovative system accumulated up to 746.50 m3 more stormwater compared to a traditional system, which was 49.2% of the total retention capacity of the drainage system, with a value of 1515.76 m3. The approach to reduce the growing flood risk in cities provided the right approach to long-term urban drainage system planning, especially since traditional drainage systems are still the leading way to transport stormwater in cities. In addition, the innovative sewage system gives the possibility of favorable cooperation with any objects (LID) and retention tanks with any hydraulic model. The implementation of an innovative system allows achieving significant financial savings and reducing the need to reserve areas designated for infrastructure investments.

Engaging professionals in urban stormwater management: the case of China’s Sponge City

ABSTRACT The initiative of Sponge City has been launched in China to manage stormwater in cities. This study aims to understand the motivation of professionals in advocating for sponge cities and their opinions on implementing sponge measures. This study surveyed 443 water and planning professionals who have been involved in sponge cities in South China, which is an area that is located in the subtropical climate zone with abundant rainfall and serious urban stormwater issues. A ‘crisis-action’ model that was established in this study revealed that professionals’ crisis awareness on urban flooding, water pollution and water scarcity would make them feel responsible for water protection, recycling and conservation, and the recognition of sponge cities as the advantageous solution would trigger their advocacy for the related policy. The professionals’ opinions on the feasibility of the sponge measures that have been proposed at the national level pointed to complex factors such as precipitation, urban density and cost-effectiveness in implementing Sponge City at the local level. This study also found some demographic differences in the responsibility and support for the Sponge City initiative. The results call for a more collaborative work platform for engaging various professionals in urban stormwater management.

Application of a rainfall-runoff model for regional-scale flood inundation mapping for the Langat River Basin

Rapid growth in recent decades has changed engineering concepts about the approach to controlling storm water in cities. Over the past years flood events have occurred more frequently in several countries in the tropics. In this study the behavior of Langat River in Malaysia was analyzed using the hydrodynamic modeling software (HEC-RAS) developed by the ‘Hydrologic Engineering Center, U.S. Army Corps of Engineers’, to simulate different water levels and flow rates corresponding to different return periods from the available database. The aim was to forecast peak flows, based on rainfall data and the maximum rate of precipitation in different return periods in storms of different duration. The maximum flows were obtained from the Automated Geospatial Watershed Assessment tool for the different return periods, and the peak flows from extreme rainfall were applied to HEC-RAS to simulate different water levels and flow rates corresponding to different return periods. The water level along the river and its tributaries could then be analyzed for different flow conditions.

Rainfall-Runoff Simulations to Assess the Potential of SuDS for Mitigating Flooding in Highly Urbanized Catchments.

Sustainable Urban Drainage Systems (SuDS) constitute an alternative to conventional drainage when managing stormwater in cities, reducing the impact of urbanization by decreasing the amount of runoff generated by a rainfall event. This paper shows the potential benefits of installing different types of SuDS in preventing flooding in comparison with the common urban drainage strategies consisting of sewer networks of manholes and pipes. The impact of these systems on urban water was studied using Geographic Information Systems (GIS), which are useful tools when both delineating catchments and parameterizing the elements that define a stormwater drainage system. Taking these GIS-based data as inputs, a series of rainfall–runoff simulations were run in a real catchment located in the city of Donostia (Northern Spain) using stormwater computer models, in order to compare the flow rates and depths produced by a design storm before and after installing SuDS. The proposed methodology overcomes the lack of precision found in former GIS-based stormwater approaches when dealing with the modeling of highly urbanized catchments, while the results demonstrated the usefulness of these systems in reducing the volume of water generated after a rainfall event and their ability to prevent localized flooding and surcharges along the sewer network.

Tool to address green roof widespread implementation effect in flood characteristics for water management planning

Abstract. In the last decades, new approaches were adopted to manage stormwater as close to its source as possible through technologies and devices that preserve and recreate natural landscape features. Green Roofs (GR) are examples of these devices that are also incentivized by city's stormwater management plans. Several studies show that GR decreases on-site runoff from impervious surfaces, however, the analysis of the effect of widespread implementation of GR in the flood characteristics at the urban basin scale in subtropical areas are little discussed, mainly because of the absence of data. Thereby, this paper shows results related to the monitoring of an extensive modular GR under subtropical weather conditions, the development of a rainfall–runoff model based on the modified Curve Number (CN) and SCS Triangular Unit Hydrograph (TUH) methods and the analysis of large-scale impact of GR by modelling different basins. The model was calibrated against observed data and showed that GR absorbed almost all the smaller storms and reduced runoff even during the most intense rainfall. The overall CN was estimated in 83 (consistent with available literature) with the shape of hydrographs well reproduced. Large-scale modelling (in basins ranging from 0.03 ha to several square kilometers) showed that the widespread use of GRs reduced peak flows (volumes) around 57% (48%) at source and 38% (32%) at the basin scale. Thus, this research validated a tool for the assessment of structural management measures (specifically GR) to address changes in flood characteristics in the city's water management planning. From the application of this model it was concluded that even if the efficiency of GR decreases as the basin scale increase they still provide a good option to cope with urbanization impact.

Analysis of Emission Reduction Measures of City Stormwater Runoff and Facility Size

This paper analyzes the urban runoff reduction measures facilities scale. Analyze and conclude the relationship data between existing-pipeline-controlled rainfall return period and runoff coefficient, by using source control. Calculate and conclude the design scale of ecological measures and storage pools, draw the corresponding generalized model, by using peak flow reduction, volume reduction and flow reduction measures.

Monitoring of clogging evolution in the stormwater infiltration system and determinant factors

Infiltration is widely used to manage stormwater in cities and their suburbs. Despite its advantages, questions remain about its long-term performance, in particular the potential for clogging. To address this problem, a field study was undertaken to assess the evolution of clogging over time by means of hydraulic resistance (R) measurements. The experiment was carried out on an infiltration basin continuously monitored for 7 years from 2004 to 2010. The work shows that clogging takes place progressively and can be slowed down by the growth of vegetation. It also showed that the variation from one event to another presented high variability. The variation of successive R-values per time unit has been statistically explained by the variation per time unit of two groups of factors: one linked to physical aspects (water volume and particle load), and more interestingly one linked to biological clogging (solar energy and air temperature), which is generally not considered for these systems. L’infiltration est aujourd’hui largement utilisée dans la gestion des eaux pluviales en milieu urbain. Malgré ses avantages, son efficacité sur le long terme pose encore problème en particulier leur aptitude au colmatage. Pour traiter ce problème, des observations de terrain ont été menées de manière à évaluer l’évolution du colmatage au cours du temps à l’aide de mesures de résistance hydraulique (R). L’observation a été menée sur un bassin d’infiltration suivi en continu sur 7 ans de 2004 à 2010. Le travail montre que le colmatage est très progressif est peut être ralenti par la croissance de végétation. Il montre également une grande variabilité d’un évènement à l’autre. La variation entre deux valeurs de R par unité de temps a pu être expliquée statistiquement par les variations par unité de temps de deux groupes de facteurs : l’un lié à des aspects physiques (volume d’eau et charge particulaire) et de manière plus intéressante à des facteurs biologiques (énergie solaire et température d’air) non considérés habituellement.

Paviršinių nuotekų valymo įrenginiuose susidarantys nuosėdų kiekiai ir jų dinamika ateityje

Didėjant paviršinių valymo įrenginių skaičiui, taip pat didėja ir valymo įrenginiuose sukauptų nuosėdų/dumblo kiekiai. Nuosėdos gali būti užterštos įvairiomis organinėmis medžiagomis, naftos produktais ir kitais teršalais. Per metus iš keturių Vilniaus paviršinių nuotekų valymo įrenginių susikaupia apie 700 m3 nuosėdų/dumblo, o įgyvendinus Vilniaus miesto bendrojo plano sprendinius šis kiekis gerokai padidėtų, ir toliau susidarant šioms nuosėdoms 2025 metais jau susikauptų apie 75 600 m3 nuosėdų/dumblo.

Storm Sewer Infrastructure Planning with Climate Change Risk: The City of Alexandria Virginia Case Study

The City of Alexandria, Virginia, has experienced repeated and increasingly frequent flooding events attributable to old infrastructure, inconsistent design criteria, and perhaps climate change. The purpose of this project is to provide a program that, over a period of up to 5 years, will analyze storm sewer capacity issues, identify problem areas, develop and prioritize solutions, and provide support for public outreach and education. The purpose of the first task was to review and propose revisions to the City's stormwater design criteria, including benchmarking of design criteria from neighboring jurisdictions, updated precipitation frequency results, evaluation of climate change risk. This paper summarizes potential changes in intensity, duration, and frequency (IDF) values, as well as sea level rise values, that were determined based on the results of general climate models paired with a range (low to high) in greenhouse gas emission scenarios. In addition, modeling of stormwater capacity under current design storm and projected storm intensity for the year 2100 are presented.

Stream Water Quality and Service Learning in an Introductory Biology Class

Northland College is a small environmental liberal arts college in northern Wisconsin near Lake Superior. In the fall of 2007 and 2008 students in a mixed science majors/non-majors introductory biology course engaged in a semester-long, service-learning project to monitor E. coli in city stormwater draining into Bay City Creek, a small stream that flows through campus and the town of Ashland before flowing into Lake Superior. Such monitoring is beyond the budget of most municipalities, but is an important public health and aesthetic issue for Ashland and Lake Superior. Our hypothesis was that this service-learning research project would have a positive impact on student learning and student perception of science, and the project would generate useful information for city leaders. Students collected and processed water samples using a standard protocol, analyzed the effect of stormwater on stream water quality, and presented their data in the form of posters to the mayor, a city administrator, and the Provost. Student learning was assessed by a poster-grading rubric, and by online and Northland College instruments. Student perceptions of science were found to be more positive than in the year preceding this project, even when clear answers were not found from their scientific investigation, and there appeared to be no distinction in responses between science majors and non-majors.

Forensic Engineering Analysis Of Alleged Property Damage From Construction Vibrations

The Influence Of Construction And Pile Driving Vibrations On Surrounding Buildings, Including Hospitals And Eye Examination Facilities, Sensitive Devices Such As Computers And Surgical Microscopes Or Electronic Machines, And People In The Urban Environment Is A Significant Consideration In Obtaining Project Approvals From Appropriate Agencies And Authorities. Implementation Of Construction Projects In Areas Adjacent To Existing Buildings (Aged, Historical, Residential, Commercial, Industrial, Medical Services, Or Electronic Services) Creates Additional Difficulties. Specialized Case History Is Presented Where Damage To Sensitive Structures From A Variety Of Vibratory Construction Methods Ranging From Pile Driving, Highway Construction, Rock Excavation And/Or Blasting, Was Considered. Twenty Homeowners From A Residential Subdivision In The Florida Panhandle, Claimed Damage Including Cracking To Their Properties During Construction Of Various Portions Of City Storm Water Treatment/Enhancement Project. It Was Also Alleged That During Excavation And Construction Of Drainage Structures, Especially Four Subsurface Treatment Vaults That Required Installation And Extraction Of Sheet Piles Using Vibratory Hammer, Stability Of The Nearby Residential Structures Was Endangered And Resulted In Movement/Cracking. Forensic Engineering Analysis Was Effectively Utilized To Identify, Investigate, And Remediate The Concerns As Well As Assist In Litigation And In Some Cases Avoidance. This Technical Paper Presents Some Legal Issues Related To Litigation, Mediation, And Resolution Involving Jurisprudence System And Introduces A Case History That Includes All Elements Of Forensic Engineering.