Stormwater Management Infrastructure Research Articles

Contribution of different land use catchments on the microplastic pollution in detention basin sediments

The assessment of microplastic (MP) pollution in urban areas is essential considering its abundance in freshwater, particularly due to urban wet weather discharge. The precise sources of MPs must be identified to better understand its characteristics. This study examines the relationship between MP pollution in detention basin sediments and land use in the investigated catchments. The study of stormwater management infrastructure, mainly in detention basins, has enabled the quantification of MP abundance in sediments conveyed by stormwater in urban areas. Sediment sampling was conducted in ten detention basins and one combined sewer overflow (CSO) structure in the Lyon metropolitan area, France. These basins correspond to stormwater outlets of representative urban catchment areas. MP extraction involves densimetric separation and organic matter degradation. MPs were then characterized using micro-Fourier infrared spectroscopy and siMPle software. This protocol identified MPs between 50 and 500 μm in the study sites. This study highlights the high abundance in the collected sediment samples, ranging from 2,525 to 1,218,82 MP kg−1 by dry weight sediment. The MPs found have a median size around 115 μm, making them very small MPs that are mainly composed of polypropylene followed by polyethylene and polystyrene or polyethylene terephthalate. The abundance of MPs in sediments is associated with the land use type. Catchments in predominantly industrial and commercial zones were more significantly polluted with MPs compared with those in predominantly agricultural or heterogeneous zones. Finally, statistical analyses revealed links between sedimentary and urban parameters and MPs concentrations. Several recommendations are given for future research, notably concerning the analyzing of stormwater sediments to understand the sources of MP pollution.

Design and Modelling of Urban Stormwater Management and Treatment Infrastructure for Communities in Wuse, Abuja

Effective stormwater management can be used to regulate water quantity and quality for environmental sustainability, flood control, pollution reduction and other advantages of civil engineering infrastructures. Pollution of the environment and contamination of water sources can emanate from improper stormwater management. This study used a small-scale model of rainwater harvesting to analyze the design and model of urban stormwater management and treatment infrastructure for the neighborhoods in Abuja. The water quality of the treated stormwater retrieved has improved as a result of the usage of memory foam, alum, and chlorine to filter out contaminants and pathogens. With the fictitious stormwater treatment model created for this study, average values of the physicochemical parameters were collected from the stormwater discharge after it had been filtered and treated. The use of potash alum has had a variety of effects on the water’s quality. From 697 mg.L-1 to 635 mg.L-1, the total dissolved solids dropped. The DO dropped from 5.87 mg.L-1 to 3.92 mg.L-1 as well. Additionally, the turbidity rose from 4.42 FNU to 4.58 FNU, and the salinity rose from 0.7 PSU to 1.44 PSU, respectively. pH decreases from 19.78 to 15.17 mg.L-1, BOD decreases from 8.35 to 6.51, and COD decreases from 2.55 to 1.9. Calcium hardness has decreased from 287 mg.L-1 to 265.83 mg.L-1. The conductivity increases marginally from 3.24 ms.cm-1 to 3.82 ms.cm-1. The Fe2+ and Zn2+ ions exhibit a little decrease from 0.143 mg.L-1 to 0.055 mg.L-1 and from 0.092 mg.L-1 to 0.045 mg.L-1, respectively. Due to inadequate or nonexistent drainage systems in the many states and villages throughout the country, stormwater run-off management and treatment in Nigeria have been a colossal failure. Effective stormwater management can be sustained by using legal and environmental laws.

Coalitional Game Theory for Stormwater Management and Green Infrastructure Practices

Coalitional Game Theory for Stormwater Management and Green Infrastructure Practices

The development of roadside green swales in the Chinese Sponge City Program: Challenges and opportunities

Roadside green swales have emerged as popular stormwater management infrastructure in urban areas, serving to mitigate stormwater pollution and reduce urban surface water discharge. However, there is a limited understanding of the various types, structures, and functions of swales, as well as the potential challenges they may face in the future. In recent years, China has witnessed a surge in the adoption of roadside green swales, especially as part of the prestigious Sponge City Program (SCP). These green swales play a crucial role in controlling stormwater pollution and conserving urban water resources by effectively removing runoff pollutants, including suspended solids, nitrogen, and phosphorus. This review critically examines recent research findings, identifies key knowledge gaps, and presents future recommendations for designing green swales for effective stormwater management, with a particular emphasis on ongoing major Chinese infrastructure projects. Despite the growing global interest in bioswales and their significance in urban development, China’s current classification of such features lacks a clear definition or specific consideration of bioswales. Furthermore, policymakers have often underestimated the adverse environmental effects of road networks, as reflected in existing laws and planning documents. This review argues that the construction and maintenance of roadside green swales should be primarily based on three critical factors: Wellthought- out road planning, suitable construction conditions, and sustainable long-term funding. The integration of quantitative environmental standards into road planning is essential to effectively address the challenge of pollution from rainfall runoff. To combat pollution associated with roads, a comprehensive assessment of potential pollution loadings should be carried out, guiding the appropriate design and construction of green swales, with a particular focus on addressing the phenomenon of first flush. One of the major challenges faced in sustaining funds for ongoing maintenance after swale construction. To address this issue, the implementation of a green finance platform is proposed. Such a platform would help ensure the availability of funds for continuous maintenance, thus maximizing the long-term effectiveness of green swales in stormwater management. Ultimately, the findings of this review aim to assist municipal governments in enhancing and implementing future urban road designs and SCP developments, incorporating effective green swale strategies.

GREEN INFRASTRUCTURE FOR PROTECTING SHIRAZ'S HISTORIC URBAN FABRIC FROM FLOODING

Shiraz, a city known for its rich historical urban fabric, faces increasing challenges posed by climate change and extreme weather events, particularly floods. The rapid urbanization and limited stormwater management infrastructure have exacerbated the vulnerability of the city's historic areas to flooding. Due to the registration of 360 km of Shiraz historical fabric in the national register in 2023, the importance of planning to safeguard this precious heritage has become twice as crucial. This study explores the potential of urban green spaces as a sustainable approach to mitigate flood impacts on Shiraz's historic urban fabric. Through a comprehensive analysis of flood patterns, urban green spaces, and historic buildings, this research aims to identify the most flood-prone areas and assess the effectiveness of existing green spaces in minimizing flood risks. The study also evaluates the role of vegetation and permeable surfaces in stormwater management to reduce floodwater runoff and its impact on historical structures. The findings reveal that strategically designed and maintained urban green spaces can act as natural flood buffers, helping to regulate water flow, reduce surface runoff, and minimize flood-induced damage to historic buildings. By integrating green spaces into urban planning, policymakers can enhance the city's resilience to floods and preserve the unique character and heritage of Shiraz's historic urban fabric. This study advocates for incorporating green infrastructure and sustainable stormwater management practices as integral to urban planning strategies. By embracing nature-based solutions, Shiraz can safeguard its historical treasures and foster a more sustainable and resilient urban environment for current and future generations. This research aimed to assess the implications of reducing urban green spaces, particularly in the green belt surrounding Shiraz's historic urban fabric and Snag-e-Siah neighborhood, on the vulnerability of historical sites to flood damage and potential demolition. With the utilization of urban green spaces, flood damage to Shiraz's built heritage was investigated in this study using both quantitative and qualitative methods simultaneously. The study results showed that the reduction of urban green infrastructure significantly increased the damage caused by floods in the historical area of Shiraz.

The economic impacts of green stormwater infrastructure: An evaluation of novel stormwater management policies in Washington, D.C.

Increases in urban stormwater infrastructure needs have led cities around the world to turn towards nature-based ‘green’ stormwater infrastructure (GI). While GI can be an effective tool for addressing many urban flooding and water quality problems, many policymakers remain skeptical of GI due to concerns about financial uncertainties and performance risks. Moreover, cost-benefit analyses of changes to urban infrastructure policies often fail to consider the economic impacts – jobs created and value added to the regional economy – of infrastructure (traditional or GI) construction. Compounding this, few studies have modeled the economic impacts of GI. In this paper, we analyze the economic impacts arising from novel development regulations requiring GI to offset impervious cover expansion in Washington, D.C (USA). Using data from a survey of GI construction firms, we determine annual, direct GI investment, and construct an input-output model to estimate indirect and induced economic impacts at the regional scale. We find that, from 2015 to 2020, GI construction supported over $91 million in average annual economic output, ∼$45 million in labor income, ∼$60 million in value added, and created (or supported) 437 jobs in the DC metropolitan region. Sensitivity analysis around regulatory stringency (higher or lower stormwater retention requirements) reveals asymmetric economic impacts that increase more given higher retention requirements than they decrease for lower retention requirements. Our analytical approach can serve as a model to help other regions produce a more comprehensive accounting of the economic feasibility of green infrastructure for urban stormwater management.

Insights into the transport and bio-degradation of dissolved inorganic nitrogen in the biochar-pyrite amended stormwater biofilter using dynamic modeling

The stormwater biofilter is a prevailing green infrastructure for urban stormwater management, but it is less effective in dissolved nitrogen removal, especially for nitrate. The mechanism that governs the nitrate leaching and performance stability of stormwater biofilters is poorly understood. In this study, a water quality model was developed to predict the ammonium and nitrate dynamics in a biochar-pyrite amended stormwater biofilter. The transport of dissolved nitrogen species was described by advection-dispersion models. The kinetics of adsorption and pyrite-based autotrophic denitrification are included in the model and simulated with a steady-state saturated flow. The model was calibrated and validated using eleven storm events. The modeling results reveal that the contribution of pyrite-based autotrophic denitrification to nitrate leaching alleviation improves with the increased drying duration. The nitrate removal efficiency was affected by a series of design parameters. Pyrite filling rate has a minor effect on nitrate removal promotion. Service area ratio and submerged zone depth are the key parameters to prevent nitrate leaching, as they influence the emergence and discharge time of nitrate breakthrough. The high inflow volume (high service area ratio) and small submerged zone can lead to earlier and increased discharge of peak nitrate otherwise the peak nitrate could be retained in the submerged zone and denitrified during the drying period. The developed mechanistic model provides a useful tool to evaluate the treatment ability of stormwater biofilters under varying conditions and offers a guideline for biofilter design optimization.

Professional differences in green infrastructure implementation: A case study of integrating engineering and ecological knowledge systems in the water sector

As water organizations adopt green infrastructure for stormwater management to increase sustainability, new types of professionals are needed that were not previously widespread in the industry. Ecologists and other ecologically-oriented employees are being brought into these organizations that have long been mostly oriented around an engineering knowledge system. This study examines how these two different knowledge systems interact within a water organization, outlining the differences in their underlying assumptions and orientations that can cause friction. The research used a case study approach to examine implementation of asset management within a water organization that has been building and managing green infrastructure for over thirty years. It found that integration around a common decision process can occur, but that it is a slow process filled with continuous negotiation. The research suggests that water organizations looking to establish green infrastructure programs should be more aware and intentional about discussing differences in professional knowledge systems when bringing new types of professions into an established organization.

Estimation of future extreme rainfall in Barcelona (Spain) under monofractal hypothesis

AbstractClimate change effects on subdaily rainfall (from 5 min to a few hours) can hardly be measured in mid‐latitude climates due to the high natural variability of the precipitation patterns and their effects on local topography. The goal of this study was to obtain change projections of intensity–duration–frequency (IDF) curves, for up to 2‐h precipitation events, comparing two approaches that use the daily outputs of the downscaled Coupled Model Intercomparison Project Phase 5 (CMIP5) multi‐model projections: (a) direct scaling of the expected probable precipitation, from 2‐year to 500‐year return periods of daily rainfall and (b) a new semi‐stochastic approach, built by combining the physically forced outputs of climate models (on a daily scale) and stochastic simulation given by the probability distribution of a concentration index (n‐index) for individual rainfall events (on a subdaily scale). The approaches were applied to a set of 27 stations located around Barcelona, Spain, including a long reference series (with 5‐min rainfall records since 1927), representing the highly variable Mediterranean climate. The validation process showed a systematic error (bias) generally smaller than 10%, especially for rainfall extreme events with durations of less than 2 h. The concentration n‐index and IDF curves were projected by 10 downscaled CMIP5 climate models under 2 emission scenarios (RCP4.5 and RCP8.5), obtaining a consensual increase in both relative concentration and absolute intensities in Barcelona. Ensemble projection of rainfall concentration (n‐index) showed an increase up to 10% by 2071–2100 and about 20% (15%–30% range) for maximum intensities of 2‐year to 500‐year return periods. Results provide robustness in decision‐making regarding the design of stormwater management infrastructure at a local scale.

<b>Issues and Strategies for Designing Flood Resilient Public Space to Achieve a Balance between Public Amenity and Stormwater Management Infrastructure</b>

<b>Issues and Strategies for Designing Flood Resilient Public Space to Achieve a Balance between Public Amenity and Stormwater Management Infrastructure</b>

Implementing green infrastructure for stormwater management and combined sewer overflow control

Implementing green infrastructure for stormwater management and combined sewer overflow control

Stochastic simulation of reference rainfall scenarios for hydrological applications using a universal multi-fractal approach

Abstract. Hydrological applications such as storm-water management usually deal with region-specific reference rainfall regulations based on intensity–duration–frequency (IDF) curves. Such curves are usually obtained via frequency analysis of rainfall and exceedance probability estimation of rain intensity for different durations. It is also common for reference rainfall to be expressed in terms of precipitation P, accumulated in a duration D, with a return period T. Meteorological modules of hydro-meteorological models used for the aforementioned applications therefore need to be capable of simulating such reference rainfall scenarios. This paper aims to address three research gaps: (i) the discrepancy between standard methods for defining reference precipitation and the strong multi-scale intermittency of precipitation, (ii) a lack of procedures to adapt multi-fractal precipitation modelling to specified partial statistical references, and (iii) scarcity of proper multi-scale tools to quantitatively estimate the effectiveness of such simulation procedures. Therefore, it proposes (i) a procedure based on extreme non-Gaussian statistics in two scaling regimes due to earth's finite size to tackle multi-scale intermittency head on, (ii) a renormalization technique to make simulations comply with the aforementioned partial statistical references, and (iii) multi-scale metrics to compare simulated rainfall time series with those observed. While the first two proposals are utilized to simulate reference rainfall scenarios for three regions (Paris, Nantes, and Aix-en-Provence) in France that are characterized by different climates, the last one is used to validate them. The scope of this paper is that the baseline precipitation scenarios simulated here can be used as realistic inputs into hydrological models for applications such as the optimal design of storm-water management infrastructure, especially green roofs. Although only purely temporal simulations are considered, this approach could possibly be generalized to space–time as well.

Green Infrastructure and Urban-Renewal Simulation for Street Tree Design Decision-Making: Moderating Demands of Stormwater Management, Sunlight and Visual Aesthetics.

The design of green infrastructure in urban renewal sites is complex, requiring engagement with existing communities and future sustainable development goals, consideration of existing and future urban forms, changing climatic conditions, and the sites often being in low-lying and flood-prone areas. Traditional street tree decision-making approaches are inadequate for addressing the scale, environmental complexity, and mutability of decisions involved in urban renewal projects—new tree selection approaches that consider complex competing criteria for tree selections addressing stormwater management systems, visual assessment and solar amenity are needed. This paper describes a new method of multi-criteria street design decision modelling that combines outputs from hydrology modelling, digital procedural tree modelling and urban form analysis, with animation and gaming technologies. We evaluate our approach through application to the design of a large-scale, urban renewal project underway in Melbourne, Australia. The results of the study demonstrate the functionality of our model, which allowed the simultaneous output of streetscape visualisation, with tree selection responding to integrated stormwater management infrastructure and flooding, along with the likely overshadowing conditions of urban renewal built-form. Our multi-criteria approach makes a significant contribution to the tools available to urban designers, planners and landscape architects in their pursuit of smarter streetscape design decisions that respond to complex spatial, cultural and climatic urban challenges.

Environmental impacts of stormwater bioretention systems with various design and construction components

Nature-based blue-green infrastructure for urban stormwater management, such as bioretention systems, is considered to provide multiple benefits compared with conventional stormwater runoff quantity and quality control. There are a range of bioretention systems and design and construction can vary widely. Studies comparing environmental impacts between different stormwater bioretention systems with various design elements and construction components have been lacking and hence, this study aims to address this gap. Various designs of stormwater bioretention systems with differing construction components and filter media mixtures have for the first time been compared using a life cycle assessment approach. Environmental impacts related to the production, transportation, and installation phases (i.e. before operation) of four types of bioretention systems, encompassing 11 configurations, have been assessed. The various construction components and filter media mixtures used incur differing degrees of environmental impacts. The filter media mixtures requiring longer transportation distances were associated with the highest environmental impacts. In this analysis, the bioretention systems built with more kerb stone, without geotextile and a filter media with sand, soil and gravel incurred the lowest environmental impacts. Whereas the bioretention systems constructed with the most concrete and with filter media that included pumice incurred the highest environmental impacts in all categories, up to 9–24 times greater than the systems with less concrete and no pumice. When means of transportation and distances were considered further in the sensitivity analysis, the concrete intensive structures incurred the highest environmental impacts. These findings can improve design choices and selection of construction components for stormwater bioretention systems where environmental impacts are considered important. • Comparing various blue green infrastructure bioretention designs with LCA approach. • Construction components used in bioretention systems incur environmental impacts. • Differing design elements and types of system incur different impacts. • The greatest environmental impacts are associated with the use of concrete and pumice. • The material transportation phase accounts for the largest environmental impacts.

Rethinking urban storm water management through resilience – The case for using green infrastructure in our warming world

Urban flooding is one of the greatest threats to life and property, further exacerbated by the impacts of a warming climate. Balancing the increasing demand for liveable space with infrastructure for urban stormwater management presents a planning conundrum. Traditional thinking and design in urban stormwater is reaching limits in adequacy, or have foreboding implementation costs. We argue that a shift in design philosophy from resisting flooding to resilience can reframe this challenge towards viable solutions. We also propose that a simpler way of assessing urban flood resilience is needed to make the shift away from a single event design approach. To that end a Simple Urban Flood Resilience Index (SUFRI) is developed as the basis and the tool for rethinking urban flood management in a future climate. SUFRI offers a “simple” framework for urban flood management as it is based only on hydrologic and hydraulic modelling. We use SUFRI to evaluate the use of green infrastructure in combatting the threat of urban flooding in warmer climatic conditions. Results show that green infrastructure remains effective during more frequent storms (~ 80th percentile) that can occur in warmer climatic conditions and retrofitting or converting a smaller than expected percentage of the urban landscape (up to 5 %) can yield appreciable benefits. Overall, we show that the flexibility and adaptability needed to address the highly variable urban flood response in warmer climates is implicit within resilience based flood management approaches.

Cost-Benefit Analysis of Green Infrastructure for Sustainable Stormwater Management of the Built Environment

Green infrastructure is a modern network of decentralized stormwater management applications that can capture and infiltrate rain where it falls, thus diminishing stormwater runoff and improving the health of surrounding waterways. While there are unique scales of green infrastructure, such as large swaths of land set aside for preservation. Green infrastructure such as bioretention, green roofs, trees, and permeable pavement is important in today’s world since many municipalities are faced with the issues of aging gray infrastructure, impaired local water way, and projected population growth by 2030. Green stormwater infrastructure helps strengthen communities’ economy while providing environmentally and economically sustainable solutions to stormwater management issues. This study found that current stormwater runoff issues in municipalities across the United States will be substantially decreased with about 1.05 billion gallons diverted from sewer. This will yield about millions of dollars in annual savings and decrease buildings energy metered water use by 1.37 million kWh of carbon dioxide. Green infrastructure is needed to address and plan for the future impacts of climate change by preventing increased flood risks and public health stresses.

Revising green roof design methods with downscaling model of rainfall time series.

Historically, green infrastructure for stormwater management has been event-based designed. This study aims to realign the green infrastructure design strategies with principles for robust decision making, through the example of green roofs design with the variational method and exemplified using the Norwegian context of the 3-step approach (3SA) for stormwater management. The 3SA consists of planning solutions to handle day-to-day rain at site scale through infiltration (step 1) and detention (step 2), and extreme events with safe floodways (step 3). An innovative framework based on downscaling of rainfall timeseries is suggested as follows: (i) long duration continuous simulation for retention variation and day-to-day discharge, corresponding to step 1 in the 3SA; (ii) intensive sampling of local extreme events to estimate reliability and robustness of solutions, corresponding to steps 2 and 3 in the 3SA. Comparing the traditional variational method to Highly-Informed-Design-Evaluation-Strategy (HIDES), it was found that the variational method possibly leads to incorrect decisions while the suggested novel approach was found to give more informed and reliable results by suggesting a design based on both operating mode and failure mode. It allows to embed solutions within the urban water system by facilitating the link between the steps of the 3SA. Such a framework was found to be data-wise applicable in the Norwegian context.

Nature-Based Solutions for Storm Water Management—Creation of a Green Infrastructure Suitability Map as a Tool for Land-Use Planning at the Municipal Level in the Province of Monza-Brianza (Italy)

Growing and uncontrolled urbanization and climate change (with an associated increase in the frequency of intense meteoric events) have led to a rising number of flooding events in urban areas due to the insufficient capacity of conventional drainage systems. Nature-Based Solutions represent a contribution to addressing these problems through the creation of a multifunctional green infrastructure, both in urban areas and in the countryside. The aim of this work was to develop a methodology to define Green Infrastructure for stormwater management at the municipal level. The methodology is defined on the basis of three phases: the definition of the territorial information needed, the production of base maps, and the production of a Suitability Map. In the first phase, we define the information needed for the identification of non-urbanized areas where rainwater can potentially infiltrate, as well as areas with soil characteristics that can exclude or limit rainwater infiltration. In the second phase, we constructed the following base maps: a “map of green areas”, a “map of natural surface infiltration potential” and a “map of exclusion areas”. In phase 3, starting from the base maps created in phase 2 and using Geographical Information Systems’ (GIS) geoprocessing procedures, the “Green area compatibility map to realize Green Infrastructure”, the “map of areas not suitable for infiltration” and the final “Green Infrastructure Suitability Map” are created. This methodology should help municipal authorities to set up Green Infrastructure Suitability Maps as a tool for land-use planning.

The Efficacy of Whole Oyster Shells for Removing Copper, Zinc, Chromium, and Cadmium Heavy Metal Ions from Stormwater

This research investigates the use of a common food waste product for removing four different types of metals typically found in stormwater. Whole, unprocessed oyster shells are explored for use in stormwater management infrastructure that addresses water quality concerns. The role of the shells’ surface area, exposure time, and the solution’s initial concentration on the removal efficiency were examined. Beaker scale experimental results demonstrated very good efficiency by the oyster shells for removing copper ions (80–95%), cadmium ions (50–90%), and zinc ions (30–80%) but the shells were not as effective in removing hexavalent chromium (20–60%). There was a positive relationship between initial concentration and removal efficiency for copper and zinc ions, a negative relationship for hexavalent chromium, and no relationship was found for cadmium ions. There was also a positive relationship between surface area and removal efficiency, and exposure time and removal efficiency. However, after a certain exposure time, the increase in removal efficiency was negligible and desorption was occasionally observed. A mid-scale experiment to mimic real-world conditions was conducted in which continuous inflow based on a 6-h design storm was applied to 2.7 kg of whole, unprocessed oyster shells. The shells provided an 86% and an 84% removal efficiency of cadmium and copper ions, respectively, in one day of hydraulic retention time. No removal was observed for hexavalent chromium, and zinc ion removal was only observed after initial leaching. This work has significant implications for sustainable stormwater infrastructure design using a material commonly found in municipal food waste.

Performance assessment of sponge city infrastructure on stormwater outflows using isochrone and SWMM models

Sponge city construction in China is integrated with stormwater management infrastructure, which is based on the concept of low impact development, such that the urban flooding and nonpoint storm pollution are mitigated. We hypothesize that an analytic framework based on isochrone and SWMM models can be used to simulate and compare the rainfall-runoff process before and after sponge city construction and thus assess the performance of the sponge city infrastructure on controlling stormwater outflows. In this paper, the analytical framework driven by design storms (with return periods of 2, 5, 20, and 30-year) was developed and tested in the catchment in Fengxi New City, China. The modeling results were then analyzed with indicators like peak flow rate, outflow volume, rainfall-runoff ratio, and stormwater stored due to sponge city construction. Outflow hydrographs and volume curve analyses showed that the sponge city infrastructure significantly mitigates the risk of stormwater overflows in the catchment and dramatically relieves the pressure on the flood control system of its downstream areas by a firm limit of the peak flow rate. Also, the performance generally decreases as rainstorms become less frequent and more intense. We anticipate that the proposed framework provides a practical approach to quantifying the sponge city's response to rainfalls under complex models.