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Previously developed analytical stochastic models (ASMs) have the limitations in that they can only be individually applied for specific end-of-pipe or low impact development facilities. This paper proposed a framework of ASMs that can be used for easily analyzing different types of storm water control measures (SCMs). The effective storage capacity for either storage-based or infiltration-based control measures was defined and formulated. Various inflow and outflow patterns of specific SCMs were also considered and analyzed. This framework also provides better insights into the similarities and differences among the model structures of different SCMs. Case studies with six climatically different locations in China and the U.S., different soil properties and six types of SCMs demonstrated the effects of various factors on runoff reduction ratios. Despite the limitations of the proposed framework such as the assumption of exponential distribution for rainfall event characteristics and the unavailability to perform single rainfall event simulation, it can still be used as a convenient toolkit to make fast and comprehensive decisions in selecting different SCMs for a specific runoff control target in design practices. [ABSTRACT FROM AUTHOR]

Astragalus is the vegetation of many mountains of Iran's plateau and plays a major role in providing ecosystem services due to its pillow shape and deep rooting system, they facilitate the control and penetration of precipitation into the soil. The correlation of Astragalus ecosystems with arid and semi-arid climates has made them vulnerable to climate change. In this study, a runoff yield map based on the Budyco curve under current and future conditions of climate change (2050) was prepared using climate and temperature data from the Chelsea site (CanESM2 GCM) in TerrSet software and by using maps of sub-watersheds, annual precipitation, annual potential evapotranspiration, soil depth, plant accessible water and the current and future "Land Cover - Land Use" map, with a combination of field methods and species distribution models at the local scale of the Shur River watershed of Dehaghan (Central Zagros). Finally, the excess runoff damage produced due to climate change was estimated using the replacement cost method. The results indicated an increase in the annual runoff volume of the watershed from 70 million cubic meters to 105 million cubic meters under climate change conditions for the RCP26 scenario in 2050. Taking into account the cost of 10 million Rials for controlling 530 cubic meters of runoff through various watershed management projects, preventing the damages of excess runoff produced requires a credit amounting to 660 billion Rials based on the present value. This study proved the ability of TerrSet software to predict and produce an ecosystem service map of runoff yield under climate changes or land use changes and with the purpose of valuation on a local scale. Also, the above valuation can be the basis for planning and providing credit for the study and implementation of watershed management projects to deal with the threats of climate change.

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Shifting from traditional puddled transplanted rice to mechanized drilled-seeding, combined with rotary straw mixing and furrow irrigation, has proven to be a crucial strategy for reducing methane emissions while optimizing resource utilization and productivity. However, this technique introduces other challenges, such as furrow runoff and soil erosion, which contribute to the degradation of ridge/bed soil quality, fertilizer loss, and transport of agroecological pollutants. Therefore, this study explores a hybrid variable flux irrigation (VFI) model as a decision support tool to mitigate these limitations by controlling soil anoxia and runoff in furrow-irrigated rice after straw incorporation. The approach integrates the Hydrus 2D/3D with optimal loop controllers to adjust pump operations based on specific soil moisture levels, variable flux, and furrow water flow depths. Experimental validation and a field case study were conducted in Babaiqiao, Nanjing City, China, where rotary straw mixing and furrow-ridge layouts were applied alongside dry rice seeding and soil hydraulic experiments. The performance indicators of the Hydrus 2D/3D variable flux demonstrated reliable simulation of lateral wetting rates and soil moisture content with R2 of 0.79 and 0.89, corresponding RMSE values of 7.90 % and 7.60 %, and MRE values of 1.85 m/day and 0.07 cm³/cm³, respectively. The VFI model proved effective, indicating that the optimal irrigation schedule consisted of three distinct supply regimes. During each cycle, the pump operated intermittently, running for approximately 2.66 hours. VFI led to a 33 % reduction in pumping energy costs while simultaneously mitigating soil anoxia and furrow runoff, thus a potential to reduce the environmental footprint of rice-wheat rotations. Although rice yields under drilled seeding were reduced by 9.56 % compared to flood irrigation due to heavy weed infestation, the VFI model provides valuable insights for promoting straw incorporation and implementing practical solutions that support optimal water utilization and sustainable productivity.

Permeable pavements play an effective role in reducing runoff by decreasing the impermeable area. But, conventional permeable pavements suffer disadvantages such as low resistance. To address this, the ‘high-strength clogging-resistant permeable pavement (CRP)’ has been developed. The present study aimed to evaluate the performance of the CRP model with varying percentages of coverage (A) of 25, 50, and 100%, slopes (S) of 1, 3, and 5%, as well as rainfall intensities (I) of 45, 55, 70, 90, 170, and 200 mm/h. Based on the results, there was an increase in A from 50 to 100% at I = 90 mm/h, decreased runoff coefficient (C) of 18, 15, and 13% at S of 1, 3, and 5%, respectively. At the same I, increasing S from 1 to 5% increased the C coefficient in A of 0, 25, 50, and 100% by 3, 31, 32, and 39%, respectively. Due to the ever-increasing urbanization and the subsequent increase in impervious areas, the risk of severe floods has greatly increased. Therefore, providing solutions such as the CRP model can help reduce flood risks in urban areas. The findings of this research can be used as a guide in the design of high-strength clogging-resistant permeable pavements in urban areas. HIGHLIGHTS Investigating parameters such as percentage of area covered by permeable pavements, their slope, and rainfall intensity can be effective in controlling runoff passing through permeable pavements.; Using the CRP model is significantly effective in runoff control.;

ABSTRACT A rainwater harvesting system, designed for non-potable water uses, can be helpful for runoff generation control. To evaluate this, sub-daily time steps for monitoring and continuous simulations are important tools. Therefore, this paper shows a performance assessment of a rainwater harvesting system for both roof runoff control (maximum flow rate and drained volume) and to meet water demand, from data obtained in a monitoring apparatus and also from continuous simulation using 1-minute time steps data. The model SWMM was calibrated and validated for both a roof and a monitoring apparatus during the monitored period 2018-2019. Thereafter, continuous simulations were accomplished using rainfall, evaporation, and demand time series. For this stage, data satisfied nearly seven years (2014-2020) containing one-minute time step values. Results have shown the control is influenced by the combined action of the first-flush diverter and rainfall regime and was shown to be greater at maximum flow rate than volume.

LRT Depo is a vital infrastructure in the operation of Jakarta's LRT system. The LRT Depo is located in the Kelapa Gading area. Kelapa Gading is an inundation-prone area in Jakarta. Hence a drainage system should be prepared to manage surface runoff in the area to avoid additional runoff to the surrounding drainage system. In order to reduce runoff in Jakarta Special Province, the Governor of Jakarta has imposed a regulation on surface runoff management for every developed area. The runoff control measures, promoted in the regulation to be applied, are in the form of infiltration wells and storage ponds. The principle of reducing peak discharge by a possible storage system for LRT Depo was designed and applied to comply with regional regulations on rainwater control. The drainage system, initially based on the regulations, was also modeled in the Storm Water Management Modelling software (SWMM). This study evaluated the drainage system by elaborating the reduction of the peak discharge based on the simulation. A reduction of peak discharge was observed in the modeling results. The proposed runoff control at LRT Depo Kelapa Gading is a proper design of infrastructure development for a flood prone area. [ABSTRACT FROM AUTHOR]

Runoff is one of the most important hydrological processes in ecosystems, which is very important in the management of water and soil resources. Although the use of soil microorganisms as soil inoculants in the bioengineering management of runoff has been confirmed, the use of soil microorganisms to control runoff in soils contaminated with petroleum has not been considered. Therefore, in order to evaluate inoculation of soil Bacteria, Cyanobacteria and fungi in reducing runoff in soil contaminated with petroleum, the present study was carried at plots of 0.5×0.5 m with slope of some 25% and level of 20000 mg kg-1 of gasoil and control contamination in three replicates. The plots will be then subjected to rainfall intensity of some 35 mm h−1 and duration of 30 min installed at the Rainfall Simulation Laboratory of Tarbiat Modares University at Faculty of Natural Resources. The results showed that the inoculation treatments, although there was no significant difference compared to the control treatment (P>0.05) except for the start of runoff (P<0.05), improved the components of runoff. The comparison of the mean of the study variables showed that the bacteria, cyanobacteria, fungi, bacteria+fungi, bacteria+cyanobacteria, cyanobacteria+fungi, and bacteria+cyanobacteria+fungi caused +47.10, -0.08, -10.72, -24.86, +14.85, +49.88 and +27.88 percent changes in runoff start time, +4.58, -54.04, +65.19, +72.20, -41.36, -84. 53 and +40.15 percent changes in runoff volume, and +4.75, +54.06 and - 65.15, +72.28, -41.39 and -84.55 and +40.20 percent changes in runoff coefficient, respectively. The results of the research indicated the relative synergistic performance of the combination treatment of cyanobacteria + fungi in reducing the effect of gasoil on runoff properties. Finally, the results of the present study showed that the inoculation of native soil bacteria, cyanobacteria, and fungi can be an efficient and sustainable biological technology to improve runoff characteristics in areas contaminated with petroleum. [ABSTRACT FROM AUTHOR]

Effective retention and interception of storm through Low Impact Development(LID)and pumping station are critical for urban waterlogging reduction. Six schemes were designed based on the spatial layout of relationships between upstream and downstream through permeable pavement, sunken greenbelt and rain barrel, and the couplings of LIDs and storage pumping station to assess the effect of runoff control of couplings of LIDs and storage pumping station in one country, Hebei province; the runoff coefficient, outflow peak and peak time in different scenarios were simulated through SWMM; the corresponding reduction rates or delayed peak time were compared in different schemes. The results show that it is effective on runoff coefficient and total outflow peak through LIDs deployed in upstream, downstream and whole area. However, implementing LIDs merely is limited in delaying the peak time and drainage of runoff in downstream pipe network; the schemes of the coupling of LIDs and storage pumping station are remarkable in reducing peak outflow whose maximum reduction rates are 23.22%, 42.88%, 44.07%, and delaying its current time 29-187 min. By comparing and analyzing the corresponding reduction rate and peak time of each scheme, it is finally concluded that the combined scheme of laying LIDs and regulating storage pumping station in the downstream have the best comprehensive benefit. [ABSTRACT FROM AUTHOR]

Biogeotextiles can be used to facilitate the formation of vegetation cover and to reduce soil erosion. Studies have demonstrated that only biogeotextile or vegetation cover can greatly reduce soil erosion. However, information about the effects of the combination of biogeotextile and vegetation cover on soil erosion is still limited, despite that the combination is the commonly practical form for bare road slope protection. Experimental plots, consisting of a relatively loose surface layer and a compacted sublayer, were constructed using movable soil-bin trolleys (200 × 100 × 40 cm3) filled with silt loam sieved through 1-cm screen. The plots were seeded with a seed mixture of tall fescue (Festuca elata Keng ex E. Alexeev) and alfalfa (Medicago sativa L.) as a grass-legume regime. Then the plots were covered with three types of biogeotextile, i.e., coir blanket (CB), mixed coir-straw blanket (MB), and straw blanket (SB). A bare slope (BS) was constructed as the control experiment. Irrigation was applied to ensure vegetation germination and growth. Plant characteristics were measured after every 20 days. Laboratory simulated rainfall of 71 mm/h intensity was applied to each plot for 60 min after 20, 40, and 60 days. Surface runoff and sediment were collected every 5 min during rainfall. The results showed that the MB and SB promoted increased total emergence density of plants by 47% and 23%, respectively, compared to case of vegetation growth without biogeotextiles. The dense structure of the CB impeded the emergence of alfalfa, leading to 9% lower total emergence density. Compared with bare slope (0 day BS), biogeotextiles increased runoff by 3% (MB)–19% (CB) and reduced erosion by 96% (MB and SB)–98% (CB). After 60 days, vegetation cover reduced runoff by 54% and reduced erosion by 81% compared with the BS case. The combination of biogeotextile and vegetation cover reduced runoff by 44% (CB)–62% (SB) and reduced erosion by no less than 99% compared to the BS case. Compared with biogeotextile alone, the combination reduced runoff by 53% (CB)–64% (SB). Compared with vegetation cover alone, the combination reduced erosion by 94% (MB)–99% (CB). The combination takes advantages of vegetation cover for long-term protection and of biogeotextile for facilitating the formation of vegetation cover and immediate erosion control. Thus, the combination is a better choice for road slope protection in northern China. These findings may promote the understanding of how biogeotextiles and vegetation cover work together for runoff and erosion control on bare slopes. In future research more attention should be paid to the selection of plant species and biogeotextile types to avoid impediment by the biogeotextile on the formation of vegetation cover like CB affected alfalfa in this study. [ABSTRACT FROM AUTHOR]

Sustainable Urban Drainage Systems (SUDS) include strategies and solutions for distributed stormwater management and control. They are strongly encouraged, especially in highly urbanized areas that suffer the combined effect of impervious surfaces and the increase in extreme rainfall events due to urbanization growth and climate change. Their integration into traditional urban drainage systems can mitigate flood risk and pollution of receiving water bodies. The main goal of SUDS is to restore the natural water balance by increasing infiltration and evapotranspiration processes and promoting rainwater harvesting and reuse. This paper proposes an analytical-probabilistic approach for SUDS modeling applicable to different systems. Developed equations allow estimating the runoff and residual storage probability for evaluating the efficiency of the storage volume both in terms of flood control and, depending on SUDS type, in terms of emptying time or water needs supply. The modeling considers the possibility of consecutive chained rainfalls; this feature is relevant for SUDS, often characterized by low outflow rates. Relating characteristic parameters to a probabilistic level (the Average Return Interval, ARI) makes the formulas interesting to be used in the design practice. An application to two case studies confirmed the goodness of the proposed method. [ABSTRACT FROM AUTHOR]

Sponge City, as a new concept in urban stormwater management, utilizes on-site or local hydrologic processes for runoff control and therefore is highly dependent on the geographical location (soil type) and site-specific climatic conditions. Field studies are valuable because of the insufficient quantity of field performance data in low-impact development (LID)-related research. Rain gardens are recommended for LID to manage stormwater. A rain garden was designed as a pilot project in Nanchang city, which is one of the typical red soil areas in southern China. Red soil is usually not conducive to runoff infiltration due to its low organic carbon, strong acidity and low permeability rainfall characteristics, but the permeability of the filter media layer is an important parameter in LID design. The construction depth of the rainwater garden was 600 mm, and 30% sand, 10% compost and 60% laterite were used as combined matrix; the permeability coefficient of medium layer was 1.48 × 10−5 m·s−1. Rainfall runoff control and pollutant removal efficiencies were studied based on the on-site conditions. The analysis of almost 2 years of field data showed that volume capture ratio of annual rainfall was 78.9%, the mean load removal of TSS, NH3-N, TP, TN, COD and NO3-N were 92.5%, 85.3%, 82.9%, 80.5%, 79.8% and 77.5%, respectively, which could meet the technical guidelines for sponge city construction in Nanchang. The research results could provide a basis for sponge city design in low organic carbon and low permeability areas. [ABSTRACT FROM AUTHOR]

Detention ponds can mitigate flooding and improve water quality by allowing the settlement of pollutants. Typically, they are operated with fully open orifices and weirs (i.e., passive control). Active controls can improve the performance of these systems: orifices can be retrofitted with controlled valves, and spillways can have controllable gates. The real-time optimal operation of its hydraulic devices can be achieved with techniques such as Model Predictive Control (MPC). A distributed quasi-2D hydrologic-hydrodynamic coupled with a reservoir flood routing model is developed and integrated with an MPC algorithm to estimate the operation of valves and movable gates in real-time. The control optimization problem is adapted to switch from a flood-related algorithm focusing on mitigating floods to a heuristic objective function that aims to increase the detention time when no inflow hydrographs are predicted. The case studies show the potential results of applying the methods developed in a catchment in Sao Paulo, Brazil. The performance of MPC compared to alternatives that do not change the operation over time with either fully or partially open valves and gates are tested. Comparisons with HEC-RAS 2D indicate volume and peak flow errors of approximately 1.4% and 0.91% for the watershed module. Simulating two consecutive 10-year storms shows that the MPC strategy can achieve peak flow reductions of 79%. In contrast, the passive scenario has nearly half of the performance (41%). A 1-year continuous simulation results show that the passive scenario with 25% of the valves opened can treat 12% more runoff compared to the developed MPC approach, with an average detention time of approximately 6 h. For the MPC approach, the average detention time is nearly 14 h, indicating that both control techniques can treat similar volumes; however, the proxy water quality for the MPC approach is enhanced due to the longer detention times achieved. [Display omitted] • A generalized quasi-2D watershed-linked-to-reservoir model is developed and tested. • The real-time operation of orifices and spillways is optimized via feedback control. • Model Predictive Control (MPC) is used to optimize the control schedules. • Two consecutive 25-year storms and 1-yr of continuous simulation are tested. • MPC results indicate superior performance for flood and water quality control. [ABSTRACT FROM AUTHOR]

Shifting from traditional puddled transplanted rice to mechanized drilled-seeding, combined with rotary straw mixing and furrow irrigation, has proven to be a crucial strategy for reducing methane emissions while optimizing resource utilization and productivity. However, this technique introduces other challenges, such as furrow runoff and soil erosion, which contribute to the degradation of ridge/bed soil quality, fertilizer loss, and transport of agroecological pollutants. Therefore, this study explores a hybrid variable flux irrigation (VFI) model as a decision support tool to mitigate these limitations by controlling soil anoxia and runoff in furrow-irrigated rice after straw incorporation. The approach integrates the Hydrus 2D/3D with optimal loop controllers to adjust pump operations based on specific soil moisture levels, variable flux, and furrow water flow depths. Experimental validation and a field case study were conducted in Babaiqiao, Nanjing City, China, where rotary straw mixing and furrow-ridge layouts were applied alongside dry rice seeding and soil hydraulic experiments. The performance indicators of the Hydrus 2D/3D variable flux demonstrated reliable simulation of lateral wetting rates and soil moisture content with R2 of 0.79 and 0.89, corresponding RMSE values of 7.90 % and 7.60 %, and MRE values of 1.85 m/day and 0.07 cm³/cm³, respectively. The VFI model proved effective, indicating that the optimal irrigation schedule consisted of three distinct supply regimes. During each cycle, the pump operated intermittently, running for approximately 2.66 hours. VFI led to a 33 % reduction in pumping energy costs while simultaneously mitigating soil anoxia and furrow runoff, thus a potential to reduce the environmental footprint of rice-wheat rotations. Although rice yields under drilled seeding were reduced by 9.56 % compared to flood irrigation due to heavy weed infestation, the VFI model provides valuable insights for promoting straw incorporation and implementing practical solutions that support optimal water utilization and sustainable productivity. • VFI modeling by integrating Hydrus 2D/3D with optimal loop controllers. • Soil anoxia and water stress conditions control by variable flux irrigation. • Mitigation of agroecological effects of straw return and furrow runoff. • Potential water and energy savings exceed 33.2 %. [ABSTRACT FROM AUTHOR]

Multi-functional rainwater storage space is a practical solution to flood and runoff pollution in high-density built-up areas. This study presents a location decision method to improve the control effect of total runoff volume, runoff peak flow, and runoff pollution. The results show that this method can accurately and quickly screen available locations for multi-functional rainwater storage space and prioritize them as optimum, suitable, less suitable, unsuitable, and not available for construction. In the case of this study, greening the road can achieve a better effect on runoff control. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Residential areas are important for the underlying surface of a city, and the sponge construction of a residential area is a key topic in sponge city construction. Taking the Zi-Jing community as the research case, the SWMM model was established for simulation, and the rainwater runoff control, collection, and utilization were compared and analyzed before and after the implementation of sponge transformation for the designed rainfall conditions of once in 3, 5, 10, 20, and 50 years. The results showed that the water depth of the four outlet pipes was not a full tube at the first peak time. The full duration time was reduced to 1–5 h at the second peak, and the flow reduction rate at the pipe outlet was between 30% and 100%. The water storage of sub-catchments A1, A3, and A4 increased significantly and continued to increase after the peak rainfall occurred, while that of A2 decreased significantly after the transformation after the transformation. For the whole residential area, the surface runoff decreased by 37–47%, while the surface water storage and infiltration increased by 8–14% and 23–39% respectively after reconstruction. The direct storage volume of rainwater in the four sub-catchment areas was filled at least once above a once in 5 years scenario. The main conclusions were as follows: Sponge transformation in residential areas with 17.46% sunken greenbelt and 40.85% permeable pavement, and the time of the pipe outlet in full status can be shortened by 30–200 min in different rainfall return periods. With the increase in the rainfall return period, the improvement range of the infiltration increased from 23.36% to 39.54%, the improvement range of the storage capacity for rainwater decreased from 14.36% to 8.06%, and the reduction degree of surface runoff increased from 37.73% to 47.43%. The water consumption for flushing is about 30 m3 per day for 1000 people, and the rainwater storage volume of 765 m3 in this study can meet the flushing water demand of 5000 residents in the community for 3–5 days. [ABSTRACT FROM AUTHOR]

With the implementation of low impact development (LID) in urban areas, it is necessary to quantify the actual effectiveness of LID facilities. In this study, a coupled hydrology-hydrodynamic numerical model was utilized to investigate the runoff control effectiveness of permeable pavements in the city centre of Shijiazhuang, China. Two groups of designed rainfall events with the same duration but different rainfall amounts and peak rainfall intensity locations were presented, and the effectiveness of permeable pavement was demonstrated by the reduction in the total runoff volume, water depth, and inundated area. The results indicate that the rainfall amount is the main factor affecting the runoff control of permeable pavements, and their effectiveness decreases with increasing rainfall amounts and peak intensity coefficients. Moreover, permeable pavements are more effective in reducing the residential waterlogging area, and the proportion of the inundated area above a depth of 0.2 m is considerably diminished. This study reveals the response of the runoff control of permeable pavements to different rainfall patterns, which is essential for supporting the design and practical operation of permeable pavements. HIGHLIGHTS Simulation scenarios with different rainfall patterns were presented to investigate the runoff control effectiveness of permeable pavement.; A series of indicators, including runoff volume, water depth, and inundated area, were presented to illustrate the runoff control effectiveness.; The effect of the relationship between rainfall intensity and infiltration rate on runoff generation was analysed.;

Today, with the expaansion of cities and the growth of urbanization, followed by climate change, it is crucial to prevent the occurrence of floods and control it in cities. Porous pavement, including porous asphalt, is known as one of the best methods for urban flood control due to its two properties of evaporation and permeability. The purpose of this study is to modify the gradation of porous asphalt in order to optimize its permeability and evaporation for low-traffic urban passages. For this purpose, permeability, evaporation, and Cantabro tests were performed on samples with different gradations and percentages of bitumen; then, using Design Expert software, the gradation and percentage of optimal bitumen were determined. Finally, the performance of the asphalt gradation and optimal bitumen percentage were evaluated by performing empty space percentage, modified Latman, Marshall, and psychological strength tests and Cantabro tests. The results show that with finer gradation, the permeability, evaporation, and minimum bitumen percentage are reduced by about 55%, 82%, and 60%, respectively. Also, the gradation is medium with 4% bitumen gradation and the percentage of bitumen is optimal, which has a good performance in low-traffic urban passages.

Green Infrastructure Development (GID) is a well‐known method for dealing with runoff control and mitigating the urbanization effects on hydrological cycles. Other than hydrological factors, GID is obviously intertwined with many socioeconomic, environmental, and aesthetic considerations, constraints, and drivers. Human perceptions are valuable resources to distinguish these considerations and can be derived from unstructured information using a systematic method. The purpose of this article is to exhibit how the perceptions of stakeholders were derived in Tehran for a conceptual model of green infrastructure development. For this, we applied a combination of Soft Systems Methodology (SSM) and Interpretive Structural Modeling (ISM). The results revealed the main stakeholders, their relationships and responsibility, main obstacles for GID, and the conceptual system of activities for GIs development in Tehran. Based on the results, actions for improving the current situation were proposed and categorized in 10 main components including: further research, regulation, financial support, negotiation with stakeholders, evaluation and monitoring, enhancing stakeholders' interactions, providing comprehensive database, acculturalization, managerial reform, and training of stakeholders. ISM was performed to obtain a visible, ordered, and well‐defined model of the relationships among the main components. The results revealed that the item "further research" plays the main role in actualizing three components "regulation," "financial support," and "negotiation with stakeholders" in the process of GID in Tehran while the realization of the rest of the components depends on the former three components. Recommendation for Resource Managers: Green infrastructure development (GID) in built cities with different stakeholders is intertwined with many socioeconomic, environmental, aesthetical considerations, constraints, and drivers, other than hydrological ones.Soft systems methodology (SSM) and interpretive structural modeling (ISM) presented in this study provided a good framework for arranging stakeholders' opinions and reaching action plans regarding GID.To change the current status of Tehran Metropolitan and move toward GID quo 10 categories of actions were proposed including: further research, regulation, financial support, negotiation with stakeholders, evaluation and monitoring, enhancement of stakeholders' interactions, providing a comprehensive database, acculturalization, management reform, and stakeholder training.More research is needed to activate three components of GID in Tehran: regulation, financial support, and negotiation with stakeholders while the realization of the other components depended on the mentioned three components. [ABSTRACT FROM AUTHOR]

Porous asphalt (PA), as a wearing course in road construction, has advantages concerning noise reduction and drainage compared to common pavements because of the high void content. In this paper, the hydrological 'linear reservoir' model approach is used to analyse and describe the drainage behaviour of porous asphalt as a whole – from infiltration to discharge. This approach includes time-dependent runoff, runoff delay due to retention and the development of discharge rates depending on water stored in the porous asphalt structure. Based on experiments, the storage constant K, describing the model parameter of linear reservoirs, is calculated and compared for different porous asphalt structures, soiling states and amounts of retained water within the porous asphalt structure. It can be shown that higher rainfall intensities and coarser mix designs lead to a lower value of K, which indicates a faster outflow. The different soiling states do not show a significant effect on the storage constant K. The influence of retention capabilities – especially the amount of undrained remaining water volume – on the drainage behaviour in general and the parameter storage constant K are discussed as well. Higher retained water volumes lead to decreased values of K. [ABSTRACT FROM AUTHOR]

A significant portion of hydrocarbons is transported by rail. At the same time petroleum products are classified as hazardous cargoes, accidents during transportation of which may lead to emergencies. The article gives an assessment of damage from emergencies in the transportation of petroleum products by rail. Assessment of economic losses, as well as damage to the environment. At damage assessment analysis of dependence of environmental damage from the time elapsed from the moment of emergency situation till the beginning of localization and liquidation of transport emergency was conducted. Technical solutions to ensure safety have been developed and proposed. The use of the proposed devices will increase the safety of transportation of petroleum products by rail. As a result of the conducted calculations the possibility of using a complex consisting of two proposed devices to ensure safety during transportation of dangerous goods has been established.

Six plots (three as controls) were established in southern Brazil to assess the reduction in runoff by vertical mulching (vm). In the other three, ditches (0.08-m wide, 0.4-m deep) were cut perpendicular to the slope, 2-m and 12-m upslope from the bottom of the plot where a flume was installed to measure runoff. Three simulated rainfalls (80 mm h−1 for 120 min, 80 mm h−1 for 65 min, 97 mm h−1 for 65 min) were applied with a sprinkler system to generate runoff. Compared to the controls, vm delayed its beginning by 10 to 20 min and reduced its volume by 34 to 39%, because initially all and later some runoff was caught in the ditches from where it infiltrated into the surrounding soil. Based on the experimental results, we derived a method to compute the runoff reduction by vm as influenced by ditch spacing (ds), initial soil moisture content (θi), and rainfall rate and duration. Computations for a combination of four ds (5 to 20 m), five θi (16 to 32%-vol), and three rainfall regimes (124 mm h−1 for 20 min, 66 mm h−1 for 60 min, and 42 mm h−1 for 120 min) showed an increasing runoff reduction as ds or θi decreased. In some cases, runoff was even completely prevented. The reductions were larger in the 60-min than in the 20-min rainfall. For the 120-min rainfall, there was no runoff with any combination of ds and θi. [ABSTRACT FROM AUTHOR]

In order to study the influence of different rainfall processes on the total pollutant load of non-point sources and pollutant load reduction rate of the low-impact development facilities, this paper took a Low Impact Development (LID) community of Tianfuheyuan, Fengxi new city, Xixian new district in Shaanxi, China as an example, and constructed the storm water management model (SWMM) of the study area. The computed results demonstrate that the storm patterns have obvious effects on the pollutant load and its reduction. The effect trend is similar to the runoff and runoff control process by LID measures. With the increase of the return period, the total pollutant load increases and the pollutant load reduction rate decreases. That is, the higher the rainfall intensity is, the less pollutant the LID measures could mitigate. Compared with the return period of 1a, the total pollutant load increased by 74.36% - 248.26% and the pollutant load reduction rate decreased by 3.67% - 10.27%, respectively, when the return period is 2a - 10a. The rain peak location has slight impact on the urban non-point source pollution. Compared with the rain peak coefficient of 0.2, the total pollutant load is decreased by 2.24% - 6.95% and the pollutant load reduction rate is increased by 0.24% - 0.74%, respectively, when the rain peak coefficient is 0.3 - 0.6. This research can help understand the mechanism of the non-point source pollution mitigated by the LID measures, and plan or design the LID measures. [ABSTRACT FROM AUTHOR]

Infiltration trenches in urban areas are mainly used for the purposes of water balance maintenance and water quality improvement. To ensure that a high enough fraction of runoff from a contributing catchment is infiltrated, trenches are usually sized to provide enough storage capacity so that runoff from a design storm of certain depth can be temporarily stored and infiltrated. Since it is difficult to quantify the actual long-term average runoff reduction ratio provided by individual trenches, their exact long-term average performances are often unknown. In this study, the closed-form analytical equations derived and verified previously for the estimation of the long-term average trench performance are applied in the practical design analysis of infiltration trenches following the detailed design guidelines of Atlanta, Georgia and New Durham, New Hampshire, U.S.. The results demonstrate that the conventional design storm-based design procedure cannot always ensure uniform trench performances because of different site soil and infiltration conditions. Use of the analytical equations (also known as the analytical stormwater models) can facilitate more accurate and consistent design of infiltration trenches because the effects of soil type, trench footprint dimensions, drain time and infiltration conditions on trench performance are all taken into consideration. The analytical equations are recommended as a convenient tool for the proper sizing of infiltration trenches so that a uniform long-term average performance can be achieved for all individual cases. [ABSTRACT FROM AUTHOR]

The exacerbation of global warming, the frequent incidence of extreme weather events, and the rapid urbanization have collectively contributed to the heightened prevalence of flooding in urban areas. As a result of this challenge, sponge city (SPC) has been adopted in China as an efficient means of preventing and controlling urban floods. To evaluate the hydrological reduction and control effect of sponge city construction (SPCC) within a university campus, a one-way coupled model integrating one-dimensional sewer hydrodynamic model (SWMM) and two-dimensional surface flow model (FVCOM), namely SWMM-FVCOM model, was established. The Nash-Sutcliffe efficiency (NSE) of the SWMM were greater than 0.75 under there rainfalls with different intensity, indicating the good reliability and stability of this model could be used in the subsequent simulation. An analysis of drainage capacity and the risk of urban flooding was conducted using this model before and after the implementation of SPCC, considering six rainfall scenarios. Implementing SPCC demonstrated an effective performance in mitigating surface runoff, regulating inspection well overflow, and reducing overflow volume in the study region. However, the efficacy of runoff control diminished proportionally with the escalation of rainfall return period. Simultaneously, the implementation of low impact development (LID) measures can significantly decrease the extent and magnitude of surface inundations. The reduction rate of SPCC on the area of waterlogging ranged from 55.84% to 72.50%. But the control rate decreased with increasing rainfall return periods, demonstrating that adopting SPCC can effectively mitigate the severity of urban flooding resulting from low rainfall return period events (Tr < 20 years). This study can provide scientific foundation for environment managers to evaluate the impact of urban flooding prevention and control on runoff pollution mitigation when adopting the implementation of SPCC. • A SWMM-FVCOM unidirectional coupling model was proposed to evaluate SPCC. • The effectiveness of the model was demonstrated through a case study. • The implementation of SPCC exhibited an effective performance in mitigating surface runoff, regulating inspection well overflow, and reducing overflow volume. • SPCC can effectively mitigate the severity of urban flooding resulting from low rainfall return period events (Tr < 20 years). [ABSTRACT FROM AUTHOR]

Low Impact Development (LID) measure is a type of sustainable engineering measure to solve the urban water problems. The runoff-control rate is considerably affected by the initial hydrological conditions. Through using Storm Water Management Model (SWMM) for Tianfuheyuan Residential Community in Xixian New Area, this work simulates the runoff control and flood peak reduction under different initial conditions for LID and traditional-development measures, respectively for a set of storms with different return periods. The results indicate that: (1) The runoffcontrol rates of natural, semi-saturated and saturated LID measures are 64.3% —83.2%, 56.3% —76.5% and 48.7% —68.1%, respectively. Compared to the natural condition, the runoff-control rates in the semi-saturated and saturated conditions are reduced by 6.7% —9.1% and 15.1% —15.8%, respectively. As the rainfall return period increases, the reduction value of runoff-control rate increases at the beginning but then decreases. (2) The runoff peaks are 23.3—189.4 L/s, 25.9—198.4 L/s and 28.8—290.7 L/s, respectively for natural, semi-saturated and saturated LID measures. In contrast with natural condition, the runoff peaks of semi-saturated and saturated conditions increase by 4.5% —20.9% and 22.9% —53.4%, respectively, indicating that the runoff-control effect of LID measures in saturated condition is far lower than that of nature condition. (3) Compared to the traditional development, LID has significant improvement for runoff control rate. The natural and semi-saturated LID measures could significantly reduce the peak runoff, but it increases under the saturated condition with the rainfall return period of 20 years, showing that the saturated LID measures may lead to higher discharge in the sewer networks downstream for heavy storms. (4) Under the same initial conditions, LID measures are able to effectively improve runoff-control rate. The research can help investigate the practical effects of LID measures. [ABSTRACT FROM AUTHOR]

ABSTRAK Penelitian dilaksanakan pada hutan tanaman mahoni (Swietenia macrophylla King.) umur 2, 5 dan 9 tahun yang berlokasi di Resort Polisi Hutan (RPH) Getas, Bagian Kesatuan Pemangkuan Hutan (BKPH) Monggot, Kesatuan Pemangkuan Hutan (KPH) Gundih, Jawa Tengah. Penelitian ini dilakukan untuk mengetahui kondisi komunitas vegetasi tegakan mahoni pada beberapa fase umur dan potensinya dalam pengendalian limpasan dan erosi. Masing-masing umur tanaman dibangun 2 petak ukur pengamatan limpasan dan erosi dengan ukuran 22,1 m x 4 m per petak ukur. Sebagai kontrol dibangun 2 petak ukur dengan ukuran yang sama pada lahan terbuka (tanpa tanaman). Pengamatan vegetasi juga dilakukan di dalam petak ukur pengamatan erosi. Hasil penelitian menunjukkan bahwa pengendalian erosi dan limpasan permukaan tegakan mahoni lebih banyak dikendalikan oleh keberadaan seresah dan tumbuhan bawah. Tingkat erosi yang terjadi pada tegakan mahoni umur 2, 5 dan 9 tahun menurun, yaitu masing-masing menjadi 49,4, 15,3 dan 8,7 % dibandingkan dengan control (lahan tanpa tanaman). Besar limpasan air permukaan pada tegakan mahoni umur 2, 5 dan 9 tahun yang dicerminkan oleh nilai koefisien erosi masing-masing sebesar 0,24 (4 % terhadap kontrol), 0,19 (24 % terhadap kontrol) dan 0,14 (44 % terhadap kontrol). Kegiatan seleksi pada kegiatan pemuliaan akan menghasilkan benih unggul yang akan meningkatkan produksi kayu (biomasa) dan menurunkan laju limpasan dan erosi. ABSTRACT The research was conducted on mahogany (Swietenia macrophylla King.) plantations at 2, 5 and 9 years old located in RPH Getas, BKPH Monggot, KPH Gundih, Central Java. This study was carried out to determine the condition of vegetation communities of mahogany stand on several phases of age and its potential in controlling runoff and erosion. Two observation plots including runoff and erosion were set up by the size of 22.1 m x 4 m per plot. Two plots of the same size were also set up on open land (without plants) as a control. Observation of vegetation was also carried out in the plot observations of erosion. This study revealed that the erosion and the runoff surface of mahogany stand controlled by the presence of litter and undergrowth. The level of erosion of mahogany at 2, 5 and 9 years old declined respectively from 49.4, 15.3 and 8.7% compared to the control (soil without plants). The runoff coefficient value which showing the water runoff in stands of mahogany age of 2, 5 and 9 years were: 0.24 (4% from the control), 0.19 (24% from the control) and 0.14 (44% from the control). The selection activities in tree breeding will improve seed mahogany therefore, can increase the wood production (biomass) and decrease the runoff and erosion.

Low impact development (LID) is a sustainable practice to managing urban runoff. However, its effectiveness in densely populated areas with intense rainfall, such as Hong Kong, remains unclear due to limited studies with similar climate conditions and urban patterns. The highly mixed land use and complicated drainage network present challenges for preparing a Storm Water Management Model (SWMM). This study proposed a reliable framework for setting up and calibrating SWMM by integrating multiple automated tools to address these issues. With a validated SWMM, we examined LID's effects on runoff control in a densely built catchment of Hong Kong. A designed full-scale LID implementation can reduce total and peak runoffs by around 35-45% for 2, 10 and 50-year return rainfalls. However, LID alone may not be adequate to handle the runoff in densely built areas of Hong Kong. As the rainfall return period increases, total runoff reduction increases, but peak runoff reduction remains close. Percentages of reduction in total and peak runoffs decline. The marginal control diminishes for total runoff while remaining constant for peak runoff when increasing the extent of LID implementation. In addition, the study identifies the crucial design parameters of LID facilities using global sensitivity analysis. Overall, our study contributes to accelerating the reliable application of SWMM and deepening the understanding of the effectiveness of LID in ensuring water security in densely built urban communities located near the humid-tropical climate zone, such as Hong Kong., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Abstract Onsite runoff control is considered an important part of sustainable urban drainage schemes, but estimating the maximum runoff flow rate from a catchment with onsite runoff controls remains controversial. Runoff controls complicate the issue by dividing the catchment into several subcatchments that feed into individual runoff controls, which dynamically regulate the catchment imperviousness. Rational Method (RM) is the most-employed technique to determine maximum flow rates for designing urban drainage infrastructures, but it cannot handle such conditions. Nonetheless, it has advantages over alternative methods in terms of principle from the urban drainage design perspective. This work develops Rational Method Prime (RMP) that follows the basic principle of RM but instead recalculates catchment variables by taking into account runoff control effects and evaluates runoff control efficiencies by using two indices. RMP has three merits: (1) providing an integrated response of the whole catchment with runoff controls; (2) interpreting runoff control effects by plotting runoff flow rate-rainfall duration curves; (3) connecting the design of runoff controls and storm sewers that are based on different design principles and rainfall statistics. Case study results showed that runoff controls reduced peak flow rates by 5.83–91.6%, corresponding to reduction factors for return period of maximum flow rate from 0.04 to 0.76. Indeed, the original RM is based on four assumptions, which also cause its weakness, and there have been current methods to address 3 of them. RMP contributes to addressing the last assumption (i.e. constant catchment imperviousness), which finally allowing the evolution from RM 1.0 to 2.0. Graphical abstract Image 1 Highlights • RMP estimates runoff peak rate from a catchment with runoff controls. • RMP interprets runoff control effects both separately and in combination. • RMP finally allows the evolution from Rational Method 1.0 to 2.0 • Rational Method 2.0 enables an integrated design of storm sewer and runoff control. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Green spaces concur to reduce flooding in urban areas providing an important ES. • Remote sensing data were used to obtain a fine-scale analysis at urban section level. • ES supply and demand were modeled to calculate a Priority Index of intervention. • The Priority Index can inform urban planning to invest in urban ES. Abstract Climate change is expected to modify the timing and amount of precipitation in the future, increasing the demand for effective adaptation at the local scale, especially to mitigate the impacts of extreme events, expected to increase in frequency and magnitude. Green infrastructure (GI) can provide a crucial water regulating ecosystem service, helping communities to adapt to the increased stormwater runoff and associated flood risks expected from climate change. This paper presents a new planning tool that utilizes remote sensing and census data to model the supply and demand for urban flood reduction services through GI. A high-resolution urban digital model is used to distinguish between permeable and impermeable areas at fine (e.g. 25 cm) spatial scale. Flood reduction capacity was modeled using two indices: i) the amount of runoff reduced by existing GI, and ii) the runoff reduction coefficient. We also analyzed the flood reduction demand using a vulnerability index. The tool is demonstrated in a historical urban center of the Northern Italy, with different scenarios used to identify priority areas of intervention. The results show that the flood reduction capacity is unevenly distributed throughout the study area. Public and private surfaces contribute different amounts of runoff with different flood reduction potentials. In eight of nine urban study areas, private properties generate more runoff than public properties under the worst scenario conditions. The study identified two priority areas of intervention, based on their mismatch between supply and demand of GI’s water regulating services. [ABSTRACT FROM AUTHOR]

Abstract: Storm water detention tanks are widely used for the control of combined sewer overflows. Conventional continuous simulation and recently developed analytical probabilistic models have been used for analyzing the hydrologic operation of storm water detention tanks. These analyses are necessary in order to accurately estimate the runoff capture efficiency of a given control system or the required storage capacity for achieving a desired runoff capture efficiency. The analytical probabilistic models still have the shortcomings of making simplifying assumptions about the initial storage conditions of a detention tank. Developed in this study is a new stochastic analysis method which can provide similar results as provided by continuous simulations and overcome some of the shortcomings of the previously developed analytical probabilistic models. This stochastic analysis method uses closed‐form analytical equations to estimate the runoff capture efficiency and required storage capacity. Results from these analytical equations are validated by comparing with continuous simulation results and close agreements are observed. These analytical equations are therefore proposed as a computationally efficient alternative for analyzing the hydrologic performance of combined sewer overflow tanks. [ABSTRACT FROM AUTHOR]

The development and construction activities of new urbanized areas lead to drastic changes in land use, resulting in severe flood disasters. The main purpose is to systematically reveal the response process to urban stormwater under different urban development degree (DD) and low-impact development (LID) implementation. A novel distributed hydrological and hydrodynamic coupled model (DHHCM), consisting of a sub-catchment-based hydrological method for plot areas and a grid-based hydrodynamic method for road areas was developed in this study. The Fengxi New Town, China was applied as the research object, a total of 11 combined events of DDs (0%, 20%, 40%, 60%, 80% and 100%) and LID deployment were simulated under five rainfall return periods (P = 2a, 5a, 30a,50a and 100a) to explore their impact on the flood process. The results indicated that the DD and the LID implementation have no obvious impact on road flood when P ≤ 5a. However, the road flood increases significantly with the increase of DD when P ≥ 30a. The peak discharge of the drainage system significantly increases with the increase in DD under different return periods, and the average peak discharge increases the most obviously (2.62 m3/s) under P = 30a. The implementation of LID measures has significantly improved the mitigation effect of surface inundation, drainage system discharge and runoff control, and its effect has increased with the DD increase. It is with great significance to accurately control the flood disaster evolution process in urban development activities, and provide data and technical support for quantifying the risks and losses in policy making. Urban flood disasters caused by urban development activities and extreme climates have become a prominent problem affecting urban public security. Quantifying the urban flood severity under different development degree and LID implementation is crucial for the assessment and early warning of flood disasters. The responses of the surface flood inundation, pipe network discharge and runoff control rate of urban development activities under different development degree and LID deployment conditions were analyzed with a novel distributed hydrological and hydrodynamic coupled mode that couples the simplified block and the fine road network for the urban rainstorm process. [Display omitted] • A novel DHHCM was developed, using hydrological method for plot areas and hydrodynamic method for road areas. • DD of the plot had no significant impact on surface water accumulation for P ≤ 5a due to sufficient drainage capacity. • LID facility reduced flooding, peak runoff, delays peak time, with highest overall runoff control when fully developed. • This study evaluated urban development's effect on runoff, guiding flood warning and rainwater management. [ABSTRACT FROM AUTHOR]

Management of urban stormwater to mitigate Combined Sewer Overflows (CSOs) is a priority for many cities; yet, few truly innovative approaches have been proposed to address the problem. Recent advances in information technology are now, however, providing cost-effective opportunities to achieve better performance of conventional stormwater infrastructure through a Continuous Monitoring and Adaptive Control (CMAC) approach. The primary objective of this study was to demonstrate that a CMAC approach can be applied to a conventional rainwater harvesting system in New York City to improve performance by minimizing discharge to the combined sewer during rainfall events, reducing water use for irrigation of local vegetation, and optimizing vegetation health. To achieve this objective, a hydrologic and hydraulic model was developed for a planned and designed rainwater harvesting system to explore multiple potential scenarios prior to the system's actual construction. Model results indicate that the CMAC rainwater harvesting system is expected to provide significant performance improvements over conventional rainwater harvesting systems. The CMAC system is expected to capture and retain 76.6% of roof runoff per year on average, as compared to just 14.8% and 41.3% for conventional moisture and timer based systems, respectively. Similarly, the CMAC system is expected to use 81.4% and 18.0% less harvested rainwater than conventional moisture and timer based irrigation approaches, respectively. The flexibility of the CMAC approach to meet competing objectives is promising for widespread implementation in New York City and other heavily urbanized areas challenged by stormwater management issues. [ABSTRACT FROM AUTHOR]

Storm water management in Singapore has always been a challenge due to intense rainfall in a flat, low-lying and urbanised catchment. PUB's (Singapore's National Water Agency) recent runoff control regulation limits the runoff coefficient to 0.55 for developments larger than or equal to 0.2 ha. The use of Active, Beautiful, Clean (ABC) Waters design features are encouraged to attain peak runoff reduction. Hence the paper focuses on (i) determining the actual hydrological response regime of Singapore using the relationship between runoff coefficient (C), land use and slope; and (ii) investigating the effectiveness of ABCWaters design features in delaying and reducing peak runoff using a modelling approach. Based on a Storm Water Management Model (SWMM) model and using elevation, land use and soil data as inputs, the peak C-values were obtained for 50 m × 50 m grid cells. The results show that for the same land use, the one with steeper slope resulted in a higher runoff coefficient. Simulations were carried out in two study areas, Green Walk District and Tengah Subcatchment, where ABCWaters design features (such as porous pavements, green roofs, rain gardens) and detention tanks were incorporated to reduce C-values. Results showed that peak C-values can be reduced to less than 0.55 after increasing the green areas and constructing detention facilities. Reduction in peak discharge (22% to 63%) and a delay in peak discharge by up to 30 min were also observed. Hence, it is recommended to consider the relationship between slope and land use while determining runoff coefficients; and to incorporate ABCWaters design features in urban design to reduce the peak flow and runoff coefficient (C). [ABSTRACT FROM AUTHOR]

Active, Beautiful, Clean Waters (ABC Waters) design features--natural systems consisting of plants and soil that detain and treat rainwater runoff--comprise a major part of Sustainable urban Drainage Systems (SuDS) in Singapore. Although it is generally accepted that ABCWaters design features are able to detain runoff and reduce peak flow, their effectiveness in doing so has not been studied or documented locally. This research aims to determine their effectiveness in reducing peak flow based on a newly constructed pilot precinct namedWaterway Ridges. Four types of ABCWaters features have been integrated holistically within the development, and designed innovatively to allow the precinct to achieve an effective C-value of 0.55 for the 10-year design storm; the precinct-wide integration and implemented design with the aim of substantially reducing peak flow are firsts in Singapore. The study is based on results from an uncalibrated 1D hydraulic model developed using the Storm Water Management Model (SWMM). Identification of key design elements and performance enhancement of the features via optimisation were also studied. Results show that the features are effective in reducing peak flow for the 10-year design storm, by 33%, and allowed the precinct to achieve an effective C-value of 0.60. [ABSTRACT FROM AUTHOR]

Green roof is one of the main infrastructures used in Sustainable Urban Drainage Systems (SUDS). Detailed design and the correct choice of materials to be applied in this type of roof are essential to obtain satisfactory hydrological performance. In recent years, numerous papers on this topic have been published. This study aimed to provide a holistic view of the main research trends for the construction of green roofs to control stormwater runoff. A systematic literature review was carried out within scientific publications from the last 5 years in the Web of Science (WoS) database. 67 papers were selected for analysis. Recent types of vegetation and materials for green roofs were listed and hydrological tests were discussed in this review. Extensive substrates were chosen by 78% of the studies due to smaller thickness, tending to be lighter and economically viable than intensive substrates. Succulents of Sedum genus were the most used in the studies due to their physiological characteristics and ability to adapt to different climates. Drainage layer consisted mainly of specific slabs commercially available for green roofs. Other layers, such as filtration, thermoacoustic insulation, and waterproofing, were also applied in many studies. The main parameters to evaluate the hydrological performance were retention capacity and runoff coefficient. In general, results showed that green roofs have considerable capacity to reduce rainwater runoff. However, many factors, such as meteorological indices, substrate antecedent moisture, and materials and plant species used can influence hydrological performance of green roofs. Some gaps were found in studies. Most of them did not compare the performance of green roofs with conventional roofs. In addition, the studies did not present cost and weight analyses, which is very important for the decision to build green roofs. [ABSTRACT FROM AUTHOR]

A field-scale data collection plan to monitor and evaluate the performance of a sediment basin design was developed and implemented using portable automatic stormwater samplers, flow modules, a rain gauge, and inflow weirs. The design configuration consisted of a skimmer as the primary dewatering device, three coir baffles installed inside the basin, polyacrylamide flocculant blocks and ditch checks in the inflow channel. A sediment basin built on a highway construction site in Franklin County, Alabama, U.S. using the aforementioned design configuration was monitored over 16 rainfall events from 15 November 2011 to 6 February 2012. The basin effectively removed sediments during the early stages of construction when the correct type of polyacrylamide flocculant blocks was used, e.g., 97.9% of sediment removal after a rainfall event on 16 November 2011. It is difficult and challenging to dose sediment-laden stormwater inflow with an exact amount of flocculating agent across all runoff producing events since rainfall is a stochastic variable. Based upon results from this study, it is recommended that a minimum volume of 251.9 m³/ha of contributing drainage area be used to sufficiently size a basin, which is still significantly under-designed for a 2-year, 24-h storm event in the southeast. This paper presents challenges and lessons learned regarding sediment basin design, monitoring, and performance that are beneficial to future studies. [ABSTRACT FROM AUTHOR]