Search Results (46)

Extreme precipitation events are one of the common hazards in eastern Texas, generating a large amount of storm water. Water running off urban areas may carry non-point source (NPS) pollution to natural resources such as rivers and lakes. Urbanization exacerbates this issue by increasing impervious surfaces that prevent natural infiltration. This study evaluated the efficacy of rain gardens, a nature-based best management practice (BMP), in mitigating NPS pollution from urban stormwater runoff. Stormwater samples were collected at inflow and outflow points of three rain gardens and analyzed for various water quality parameters, including pH, electrical conductivity, fluoride, chloride, nitrate, nitrite, phosphate, sulfate, salts, carbonates, bicarbonates, sodium, potassium, aluminum, boron, calcium, mercury, arsenic, copper iron lead magnesium, manganese and zinc. Removal efficiencies for nitrate, phosphate, and zinc exceeded 70%, while heavy metals such as lead achieved reductions up to 80%. However, certain parameters, such as calcium, magnesium and conductivity, showed increased outflow concentrations, attributed to substrate leaching. These increases resulted in a higher outflow pH. Overall, the pollutants were removed with an efficiency exceeding 50%. These findings demonstrate that rain gardens are an effective and sustainable solution for managing urban stormwater runoff and mitigating NPS pollution in eastern Texas, particularly in regions vulnerable to extreme precipitation events. Full article

Stormwater reuse plays a critical role under changing climates and increasing water demands. This study investigates the removal efficacy of lead (Pb²⁺) and ammonia (NH₃) using sand and rice husk (RH) biochar for potential stormwater quality improvements and treatments. Column experiments combined with HYDRUS inverse modeling were conducted to optimize adsorption isotherms from breakthrough curves. Among linear and non-linear models, the Langmuir and Freundlich models performed better for sand and biochar, respectively. RH biochar showed much higher adsorption capacity of both Pb²⁺ (4.813 mg/g) and NH₃ (6.188 mg/g). In contrast, sand showed a relatively limited adsorption capacity for Pb²⁺ (0.118 mg/g) and NH₃ (0.104 mg/g). This can be contributed to higher pore size distribution, surface area, and the presence of different functional groups of biochar. The optimized adsorption coefficients and adsorption capacity parameters of sand and RH biochar by inverse modeling provided useful input for improving field designs. These findings will enhance the development of the best management practices (BMPs) for managing heavy metal and solute pollution in groundwater or stormwater low-impact development (LID) infrastructure systems. Full article

This study addresses the growing inadequacies of traditional architectural concepts and techniques in stormwater management amid the increasing frequency of extreme weather events, particularly in densely built urban micro-spaces. To tackle these challenges, we propose an integrated theoretical and practical framework applied to a case study of a small-scale urban public space in Chang’an District, Shijiazhuang City, Hebei Province, covering an area of about 2.15 hectares in North China. The framework combines Best Management Practices Planning (BMP-P) with Low Impact Development Design (LID-D). The framework optimizes sub-catchment delineation, strategically locates drainage outlets, and configures network layouts to reduce runoff path lengths, thereby reducing total runoff volume, enhancing drainage capacity, and alleviating surface water accumulation, which, in turn, informs the parametric design of LID facilities. In the BMP-P phase, four source-control measures were developed based on runoff control and stormwater retention: adjusting terrain slopes, adding or removing curbs and facilities, redistributing infiltration areas, and adjusting drainage outlet and piping layouts. By shortening runoff paths and reducing potential waterlogging areas, these measures effectively reduced total runoff volume (Trv) by 31.5% to 35.7% and peak runoff volume (Prv) by 19.4% to 32.4%. Moreover, by remodeling the stormwater network with a different layout, larger pipe diameters, and substantially increased network capacity, the total discharge (Tdv) increased by 1.8% to 50.2%, and the peak discharge rate (Pdr) increased by 100% to 550%, thus minimizing surface flooding. In the LID-D phase, we developed a Grasshopper-based parametric design program for the layout and design of LID facilities. This approach significantly reduces interdisciplinary communication costs and enhances urban planning efficiency. By integrating BMP and LID strategies, the proposed framework offers a flexible, rapid, and efficient solution for achieving resilient stormwater management in the context of urban micro-renewal. Full article

Urbanization and the expansion of impervious surfaces have increased stormwater runoff volumes, altered runoff timing, and degraded water quality and aquatic ecosystems. Runoff from urban areas carries pollutants such as nitrogen, phosphorus, sediments, and heavy metals, which can adversely impact the physical characteristics of receiving waterbodies. Stormwater management programs aim to mitigate these effects using Best Management Practices (BMPs) to retain and treat stormwater on-site. However, in densely developed areas, space constraints and high costs often make traditional BMPs impractical. This study assessed the effectiveness of expanded shale, an engineered material, as a filtration medium in bioswales, a type of linear BMP commonly used in transportation infrastructure. Thirty scenarios were tested in a 16 ft (4.9 m) long plexiglass flume using expanded shale mixed with sandy clay soil. Due to the limited scope of this study, it focused on assessing the effectiveness of expanded shale in removing suspended sediments and reducing turbidity. Results showed that expanded shale achieved removal efficiencies ranging from 20% to 82% for total suspended solids (TSS) and −4% to 61% for turbidity under different conditions. It outperformed conventional filtration materials such as sand and gravel, requiring less channel length. Remarkably, even in a small-scale laboratory setting, expanded shale met the suspended sediment removal standard of 80%, demonstrating its potential as a highly effective filtration material alternative for urban stormwater management. Full article

Urbanization growth and climate change have increased the frequency and severity of floods in urban areas. One of the effective methods for reducing stormwater volume and managing urban floods is the low-impact development best management practice (LID-BMP). This study aims to mitigate flood volume and peak discharge caused by land use changes in the Darabad basin located in Tehran, Iran, using LID-BMPs. For this purpose, land use maps were extracted for a period of 23 years from 2000 to 2022 using Landsat satellite images. Then, by using a combination of geographic information system-based multi-criteria decision analysis (GIS-MCDA) method and spatial criteria, four types of LID-BMPs, including bioretention basin, green roof, grass swale, and porous pavement, were located in the study area. Next, rainfall–runoff modeling was applied to calculate the changes in the mentioned criteria due to land use changes and the application of LID-BMPs in the area using soil conservation service curve number (SCS-CN) method. The simulation results showed that the rise in built-up land use from 43.49 to 56.51 percent between the period has increased the flood volume and peak discharge of 25-year return period by approximately 60 percent. The simulation results also indicated that the combined use of the four selected types of LID-BMPs will lead to a greater decrease in stormwater volume and peak discharge. According to the results, LID-BMPs perform better in shorter return periods in a way that the average percentage of flood volume and peak discharge reduction in a 2-year return period were 36.75 and 34.96 percent, while they were 31.37 and 26.5 percent in a 100-year return period. Full article

Infiltration-based stormwater best management practices (BMPs) are progressively being utilized to mitigate issues such as increased runoff and poor water quality associated with urbanization. However, they are often difficult to accurately model due to the extensive design variables involved, particularly in high water table regions where groundwater mounding can cause primary infiltration to shift from vertical to horizontal. This study assessed an infiltration-based stormwater management system for a commercial property in Southwest Florida using integrated ArcMap 10.8.2 -ICPR4 software. A unique modeling technique captured the shift from vertical to horizontal infiltration in high water table conditions, employing ICPR4’s “percolation ring” and “percolation link”. The integration of GIS with the ICPR model enabled detailed modeling, assessment, and visualization of runoff in high water table areas. Three site-specific design storms were employed to analyze the pre- and post-developed conditions of the study area and assess whether existing BMPs met Environmental Resource Permit (ERP) requirements. While the system complies with ERP standards, it was found to be oversized based on storage basin stages and stormwater discharges from the simulated 100-year/24-h storm event. This is because 45–68% of the total volume entering the stormwater management basins infiltrated during the analysis period. The infiltration rate in the models was initially heavily dependent on vertical infiltration. However, horizontal groundwater flow substantially increased with the increasing water stage in the detention ponds after vadose zone saturation. These findings highlight the significance of modeling techniques in accurately capturing the performance of infiltration-based stormwater management systems in high water table conditions. Full article

The increase in the quantity and variety of contaminants generated during routine airport infrastructure maintenance operations leads to a wider range of pollutants entering soil and surface waters through runoff, causing soil erosion and groundwater pollution. A significant developmental challenge is ensuring that airport infrastructure meets high-quality environmental management standards. It is crucial to have effective tools for monitoring and managing the volume and quality of stormwater produced within airports and nearby coastal areas. It is necessary to develop methodologies for determining a wide range of contaminants in airport stormwater samples and assessing their toxicity to improve the accuracy of environmental status assessments. This manuscript aims to showcase the latest advancements (2010–2024 update) in developing methodologies, including green analytical techniques, for detecting a wide range of pollutants in airport runoff waters and directly assessing the toxicity levels of airport stormwater effluent. An integrated chemical and ecotoxicological approach to assessing environmental pollution in airport areas can lead to precise environmental risk assessments and well-informed management decisions for sustainable airport operations. Furthermore, this critical review highlights the latest innovations in remediation techniques and various strategies to minimize airport waste. It shifts the paradigm of soil and water pollution management towards nature-based solutions, aligning with the sustainable development goals of the 2030 Agenda. Full article

This study aims to investigate the economic effects of stormwater best management practices (BMPs) on housing sale prices in Washington, D.C., BMPs play a significant role in mitigating multiple threats, such as water pollution, soil erosion, and property damage. While studies on the economic value of BMPs were limited, literature addresses that housing sale prices can be affected by nearby stormwater BMPs. This study addresses the following research questions: Do stormwater BMPs positively impact housing sale prices? How do proximity and number of structural BMPs affect the housing sale prices? We used the hedonic pricing method by applying multiple linear regression models to determine whether a set of independent variables significantly improved the models. Our primary findings indicate that BMPs have positive, negative, or no effects on housing sale prices. The proximity of BMPs inside of parks increased housing sale prices in all buffers. In contrast, the proximity of BMPs outside of parks and impervious roads decreased housing sale prices in all buffers. Percent tree canopy coverage negatively linked to a 50 m buffer and had no relationship with other buffers on housing sale prices. This study implies that BMPs impact housing prices and can be improved by landscape architects, policymakers, and stakeholders. Full article

Stream corridor erosion can majorly contribute to the overall sediment and phosphorus load in urbanizing watersheds. However, the relative contribution of stream bed and bank erosion, compared with upland watershed sources and the potential for stream restoration to mitigate total contaminant loads, is poorly understood. In this study, a new method was developed, using the percent impervious cover (PIC) indicator of urbanization to evaluate the relative contribution of the stream corridor versus upland watershed contributions to observed total sediment and phosphorus loads in the receiving watercourse. This method was used to develop a cost-optimized mitigation plan, including implementing low-impact development (LID) stormwater infrastructure for urban areas and agricultural best management practices (BMPs) for rural areas in the watershed and stream restoration for the degraded stream reaches. A new cost–benefit analysis methodology is developed and used to assess the relative benefits of the mitigation measures for the case study of the Tannery Creek sub-watershed of the East Holland River in Ontario, Canada. The novel contributions of this study include the development of three relationships to estimate sediment and associated phosphorus loading based on contributing catchment area and land use, as well as a method to optimize the costs and benefits of planned mitigation measures. The results support stream restoration as an essential and cost-effective part of a comprehensive water quality watershed management plan to help maintain healthy streams in urbanized watersheds. 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

Nonpoint source (NPS) pollution is a severe problem in the U.S. and worldwide. Best management practices (BMPs) have been widely used to control stormwater and reduce NPS pollution. Previous research has shown that socio-economic factors affect households’ adoption of BMPs, but few studies have quantitatively analyzed the spatio-temporal dynamics of household BMP adoption under different socio-economic conditions. In this paper, diverse regression approaches (linear, LASSO, support vector, random forest) were used on the ten-year data of household BMP adoption in socio-economically diverse areas of Washington, D.C., to model BMP adoption behaviors. The model with the best performance (random forest regression, R² = 0.67, PBIAS = 7.2) was used to simulate spatio-temporal patterns of household BMP adoption in two nearby watersheds (Watts Branch watershed between Washington, D.C., and Maryland; Watershed 263 in Baltimore), each of which are characterized by different socio-economic (population density, median household income, renter rate, average area per household, etc.) and physical attributes (total area, percentage of canopy in residential area, average distance to nearest BMPs, etc.). The BMP adoption rate was considerably higher at the Watts Branch watershed (14 BMPs per 1000 housing units) than at Watershed 263 (4 BMPs per 1000 housing units) due to distinct differences in the watershed characteristics (lower renter rate and poverty rate; higher median household income, education level, and canopy rate in residential areas). This research shows that adoption behavior tends to cluster in urban areas across socio-economic boundaries and that targeted, community-specific social interventions are needed to reach the NPS control goal. Full article

Urban stormwater is known to cause a myriad of problems, ranging from flooding to water quality degradations. This paper provides an extensive review of analytical probabilistic model (APMs) used in the design of urban runoff control systems. APMs are closed-form mathematical expressions representing a long-term system’s output performance derived from the probability distribution of the system’s input variables. Once derived, the APMs are easy to handle, allow for sensitive analysis, and can be co-opted into optimization frameworks. The implementation of APM in the planning and design of runoff control systems will not only help address the runoff quantity and quality problems of urban stormwater, but will also go a long way in optimizing the benefits derived from the systems. This paper reviews studies that document the negative impacts of urbanization on runoff quantity and quality, and the best management practices (BMPs) used to mitigate the impacts. Three design methodologies used in urban stormwater control systems were reviewed. A detailed review of research on the development and use of APMs in urban stormwater management in various runoff control systems is presented, and recommendations are proffered. Full article

Urban waterways degradation due to runoff from residential areas can be reduced by adopting best management practices (BMPs) for irrigation, fertilizer, and pesticide use. Although stormwater runoff from urban areas has been studied extensively, we focus on single-family residential land use specifically. Outreach to individual households may have a measurable impact since decisions are being made here. We surveyed households to evaluate the effectiveness of education and outreach campaigns on self-reported use of water and chemicals and evaluated whether self-reported behaviors were reflected in the quality and quantity of water draining from the study areas before and after outreach efforts. Our research was conducted in California, which has a Mediterranean climate with distinct wet and dry periods. Runoff from residential landscapes during the dry season enters waterways undiluted by rainwater, making this runoff particularly detrimental to receiving waters. No significant differences in behavior and BMP adoption from before and after the education and outreach campaign was found. These results are not atypical and may be explained by several factors including the population approach to the survey, lag times between outreach and measurable effects, and the need for a critical threshold of adoption to be met for effects to be measurable. Full article

The uncontrolled urbanization of soil leads to two main effects: the increase in flood discharges due to changes in permeability capacity and the negative impact in terms of quality on water bodies. These effects can be mitigated by common engineering practices, such as Low Impact Development (LID, which generally involves stormwater treatment devices on a smaller scale rather than centralized solutions); Sustainable Urban Drainage Systems (SUDSs, a range of technologies and techniques used to drain stormwater in a more sustainable manner than conventional solutions); Best Management Practices (BMPs, suggested solutions are more focalized on pollution prevention in urban systems), and more. Among the proposed solutions, detention/retention systems and stormwater ponds can also perform excellent functions with regard to hydraulic hazards and both quantitative and qualitative control of sewer discharge, thanks to stormwater volume accumulation together with the presence of vegetation, when the basin is conceived as a natural-looking lake environment. The use of data-driven approaches could represent an effective approach for the prediction of the characteristics of the sewage tributaries, for the generation of synthetic time series of quantitative/qualitative data of sewer flows or for Real-Time Control (RTC) to reduce overflow at the Waste Water Treatment Plant (WWTP). This work shows the preliminary results obtained by applying NARX neural networks in order to estimate quality indices (the turbidity in this study) in sewer systems. The available data are discharge, temperature, gage height, specific conductivity, and precipitation, whose use as parameters for the recurrent neural network leads to values of R = 0.77–0.80 in the various combinations tested. Full article

The threat of anthropogenic eutrophication and harmful algal blooms in lakes requires the development of innovative stormwater best management practices (BMPs) to reduce the external loading of phosphorus (P). This paper presents the findings of a 5-year study of a full-scale P removal structure constructed in Minnesota, USA with spent lime drinking water treatment residual (DWTR), a by-product of water softening at a local water treatment plant. Influent and effluent water samples were collected by auto-samplers during 43 storm events during the growing season. Samples were analyzed for P constituents, heavy metals, total suspended solids (TSS), and pH. Toxicity of the effluent was assessed using Ceriodaphnia dubia. Flow-weighted removal effectiveness was calculated for each storm event. Overall, the spent lime DWTR reduced total P loading by 70.9%, dissolved reactive P by 78.5%, dissolved P by 74.7%, and TSS by 58.5%. A significant reduction in heavy metals was also observed. Toxicity tests indicated the aquatic toxicity of the effluent treated with spent lime DWTR was not different from untreated stormwater. This study provided long-term real-world data that demonstrated that a full-scale P removal structure with spent lime DWTR significantly reduced P and other pollutants in stormwater discharging to an urban lake. Therefore, spent lime DWTR, which is currently treated as a waste product, is a promising filter material for stormwater treatment. Full article