Low Impact Development Techniques Research Articles

A Review of Recent Developments on Modeling Low Impact Development (LID) Technique

Urban areas are more susceptible to flooding and water body contamination due to the detrimental effects of urbanization. As a result, a sustainable urban drainage system, also known as low impact development (LID) technique, is required. Although this technique can be extensively applied, the planning and design processes are multi-dimensional, multi-variable, and site-specific, which must consider various local conditions and factors. Consequently, these processes can be very complicated and time-consuming for professionals, necessitating support from computer modeling. This study intends to thoroughly explore the idea of LID modeling, various available computer models, and other tools for its optimization and decision-making processes. The most recent trustworthy journal publications that addressed the subjects under discussion were reviewed. This paper used the descriptive and comparative approaches as the analytical methods. According to the findings of the review, Storm Water Management Model (SWMM) is the computer model in LID modeling that is most frequently employed. This model is a fundamental package for dynamic urban rainfall-runoff modeling, and it has the benefits of being lightweight, simple to use, and an intuitive user interface. Besides, this model is public domain (free to use), open source, and interoperable with many hydro modeling applications. A specific LID editor module is also included in this model for modeling different LID units. To acquire the best LID planning and design from multiple criteria and alternatives, it is also necessary to use metaheuristic algorithms as an optimization model and a multi-criteria decision-making (MCDM) model in addition to the rainfall-runoff model. The authors believe combining the hydrologic and hydraulics models integrated with geographical information systems (GIS), metaheuristic algorithms, and MCDM is the most comprehensive and appropriate method for LID modeling in urban watersheds.

Evaluation of augmented infiltration based LIDs for low lying urbanizing coastal catchments: a case study of Chennai city, India

ABSTRACT The study assessed the effectiveness of infiltration-based Low Impact Development (LID) techniques and augmented infiltration LIDs (such as recharge shaft) in a coastal urban catchment in India using a semi-coupled approach between numerical models VS2DI and Storm Water Management Model (SWMM). Site specific VS2DI modelling indicated that the infiltration LIDs resulted in more saturation excess runoff due to the soil’s insufficient hydraulic conductivity and increased lateral flow. Catchment-scale modeling indicated that LIDs significantly improved water retention (p ≪ 0.05), with a 35% reduction in total runoff volume. The recharge shafts were shown to be more efficient in reducing runoff volume and peak runoff, particularly for high runoff rates (more than 22 mm/hr). The study suggests that direct recharge to the aquifer through recharge shafts could be a suitable solution to manage runoff and meet the demand for domestic water supply during times of water scarcity in coastal urban catchments.

Determination of the minimum soil infiltration rate of sunken green space considering the annual runoff collection ratio, sunken depth and sunken green space area of Hefei city, China.

Sunken green space is one of the urban rainwater collection facilities, which belongs to Low Impact Development (LID) techniques. It plays a key role in the construction of sponge city, and the amount of runoff collection is usually affected by the area of the sunken green space, the infiltration rate of the soil, and the annual runoff collection rate. To determine the minimum soil infiltration rate of sunken green space considering the annual runoff collection ratio of sponge cities, this paper selects a residential district in Hefei city, China, as the case study. Based on 45 years of precipitation data, the designed rainfall corresponding to annual runoff collection ratios of 75%, 80% and 85% is 21.3 mm, 23.4 mm and 27.5 mm, respectively. The characteristics of rainfall infiltration in sunken green space are analyzed by using the water balance model and runoff yield and conflux model. The results reveal that the soil infiltration rate is 1.16×10-4 cm/s~3.88×10-3 cm/s when the sunken depth is 0.1 m~0.3 m and that the ratio of green space area is 5%~25%. The runoff collection of the reconstructed sunken green space is 2.87 times and 1.98 times that of the nonsunken green space and the nonreconstructed sunken green space, respectively. That is to say, under the comprehensive performance of the sunken depth, sunken green space area, the steady soil infiltration rater of the reconstructed sunken green space cannot be less than the value obtained in this paper. Otherwise, the requirements of annual total runoff reduction ratio of the sponge city cannot be met. Therefore, this study provides references for realizing the ratio of annual runoff collection and sponge city construction in similar urban areas. It can also be applied to optimal selection of sunken green space in some sponge city projects.

Changes in the Urban Hydrological Cycle of the Future Using Low-Impact Development Based on Shared Socioeconomic Pathway Scenarios

Representative Concentration Pathway (RCP) scenarios have been used for various studies in the field of climate change. In this regard, the Shared Socioeconomic Pathway (SSP) scenario has been newly introduced to examine climate change impacts, but relevant research is still insufficient. For this reason, new SSP scenarios with a combination of Low-Impact Development (LID) techniques are applied to predict rainfall-runoff efficiency and hydrological variation. The inter-model variability in the monthly average precipitation for each GCM according to new SSP scenarios under future climate was investigated. Based on the RCP 4.5 and RCP 8.5 scenarios, the results show precipitation changes with an increase of 4.8% and 12.3%, respectively. Furthermore, precipitation projections under SSP2-4.5 and SSP5-8.5 scenarios are predicted to increase by 13.9% and 20.6%, respectively, indicating that the magnitude of precipitation increases with new climate change scenarios. The Storm Water Management Model (SWMM) during the future period indicated that LID applications will reduce runoff compared with scenarios with no LID application. In particular, the introduction of permeable pavement and infiltration trenches revealed the best runoff reduction performance among the combinations of LID techniques considered. In addition, this study projected changes in the urban hydrological cycle for the climate over the next 30 years to reflect the implementation of urban hydrological cycle plans, which take approximately 10 years. Overall, it was found that, in the future, LID applications will contribute to improving the sustainability of the urban hydrological cycle of the study area. The results of our study can provide future directions for water management strategies in Korea.

Development of a Simple Design Method for an Infiltration Facility using Curve Number

As climate change accelerates, the scale and intensity of natural disasters are increasing, and the frequency of localized heavy rains is increasing rapidly. Urban watersheds have a high ratio of impervious areas. So there is a high possibility of flooding in the event of torrential rain, and large-scale damage can occur because the population and material resources are highly concentrated. River improvements, sewerage maintenance, and rainwater storage installations are frequently used to reduce flood damage. More recently, low-impact development (LID) techniques have been proposed; however, LID facilities are installed on a small scale and in various locations. In addition, they require many parameters for a rainfall-runoff analysis; consequently, the design of these facilities require too much manpower and time. In this study, we analyze the rainfall-runoff reduction effect based on the size of a facility to present a simpler, more efficient design method. Next, the curve number (CN) corresponding to the capacity of each facility is estimated and the correlation between the facility’s area ratio and the CN is analyzed. As a result, a relational expression that can calculate the new CN with the same rainfall-runoff reduction effect as the installed LID facility was derived by using the CN before the installation of the LID facility and the facility area ratio. Thus, we present a simple design method using the recalculated CN without directly entering LID facilities into a storm water management model (SWMM).

Study of the applicability of Sponge City concepts for flood mitigation based on LID (low impact development) measures: A case study in Conakry City, Republic of Guinea.

Urban flooding is becoming a significant urban epidemic in many nations throughout the world as a result of land use and climate change, and regular heavy rains. In this study, we choose to investigate the viability of Sponge City concepts for flood mitigation based on low impact development (LID) strategies in a 26.66 km2 area situated in Guinea's capital city of Conakry. The Storm Water Management Model (SWMM5) was used to simulate the impact of LID measures on the lowering of runoff peaks and node flooding. Simulation results before and after LID facilities are compared in order to understand how LID measures improve flood mitigation. The study showed that LID techniques effectively reduce runoff, which helps mitigate the effects of flooding. The study demonstrated that all LID, whether used singly or in combination, can lower runoff and flooding. However, when it comes to reducing runoff and flooding, LID-combinations perform better than individual LID implementations. For the five return periods (one, five, 20, 50, and 100 years), the LID-combination reduced runoff by 67.83, 65.02, 50.44, 40.18, and 35.88%, and reduced flooding by 85.32, 72.65, 54.05, 46.17, and 42.80%, respectively. Additionally, the reduction rate of overflow junctions is 100, 100, 80, 67, and 70%, respectively.

Evaluating the Effectiveness of Low Impact Development Practices against Climate Induced Extreme Floods

Short but extreme flooding events have been frequent and severe globally due to climate change and urbanization in recent years. Similarly, researchers, scientists, and water managers are suggesting the application of sustainable flood management strategies such as Low Impact Development (LID) to mitigate the impacts of such extreme flooding events. However, most of these strategies have primarily been evaluated using historical precipitation events, which may not accurately represent the impact of climate-induced flooding events, which are projected to become more extreme. In this context, this study assesses the effectiveness of LIDs in combating climate change-induced flooding events. The North American Regional Climate Change Assessment Program (NARCCAP) climate model was applied in this study to quantify the magnitude of future projected storm depths, which are expected to increase due to climate change. Similarly, Personal Computer Storm Water Management Model (PCSWMM) was used to develop a rainfall-runoff simulation model and to assess the effectiveness of three LID techniques (Permeable Pavement, Green Roof, and Bio-Retention Cell) in reducing surface runoff under various climate scenarios. The results revealed that under the climate change scenarios the future projected design depths are expected to increase by up to 104%. Similarly, peak discharge, and total flooding volume were found to increase by 37.72% and 88.73%, respectively under the most extreme climate change scenario. Furthermore, the study demonstrated that applying LID strategies decreases peak discharge, offering a viable solution to tackle flooding events induced by climate change. The results illustrated the performance of permeable pavement was superior in reducing the peak discharge by up to 28.57%. Similarly, applying green roofs and bioretention cells reduced the peak discharge by up to 19.93% and 14.25%, respectively.

Assessment of Infiltration Swale Performance as a Low-Impact Development Technique in Tropical Coastal Environments

Operation of source control measures (SCM) in urban drainage in tropical/transitional climates are still a challenge because of higher rain volumes and more intense rains, as well as constraints from sea-level interference. In this study, the performance of a swale to control runoff was detailed and monitored in such an environment. The data on rain, runoff, and sea levels were acquired at a site located in an island in the south coast of Brazil. The results showed that even with higher rain volumes and more intense rains, the mean capture of the swale was 51.7% of the entrance runoff volume, but it depended on seasonal rain variation and interference of sea/tide level. As a result, the swale might be undersized in summer and oversized in winter. Peak flow retardation was observed in 97% of monitored events. The interference of sea/tide level was not directly correlated with infiltration volumes, but in the principal component analysis, the parameters of sea/tide level, along with the hydrological parameters of rain duration, height, and intensity, explained 60% of the variance in the data. In conclusion, the application of SCMs in tropical regions is suitable, but seasonality should be incorporated in the design. The interference of sea/tide level must be further investigated to verify how to incorporate its influence in the design.

Exploring an Approach to Estimate Runoff in an Ungauged Mixed Urban Micro Catchment - A Case Study, Pune, India

Sustainable and integrated water resource management needs an hour, and achieving accurate estimation of runoff is key. The decision-making on urban landscaping planning for low-impact development techniques depends largely on the accuracy of rainfall. The haphazardly developed cities in India are encountering flooding crises due to the unexpected expansion. These mixed urban catchments comprise a muddle of residential, commercial, urban-rural, and industrial zones in any combination. Due to this change in urban catchments, the hydrological cycle gets affected and results in elevated runoff volume. The solutions to these are therefore necessary to be planned at a micro catchment level. This paper aims to explore an approach to calculate the runoff of such a micro mixed urban catchment. The geographical scope of this study is the fringe boundary of Pune city. For this ungauged basin, the basic mass balance equation was used to estimate runoff values compared with the runoff values calculated from empirical equations previously developed. From this comparison, it is observed that runoff values obtained from empirical equations were underestimated, which may be due to rapid land-use caused by urbanization. Hence, a need was felt to re-evaluate the coefficients of these empirical models, which take into cognizance the current scenario and its allied changes over the years. An attempt is made to modify the coefficients of empirical equations considering precipitation as the primary parameter. These modified coefficients fetched better runoff results than the runoff results obtained from the coefficients of previously established empirical equations. However, even with these modified coefficients, the runoff results were underestimated, which may be because of not considering the physical characteristics of the catchment in these equations. Therefore, to increase the accuracy of these results, a numerical model that considers these catchment characteristics was chosen. In the present study, a dynamic rainfall-runoff model - stormwater management models (SWMM) is used and compared to assess runoff for an ungauged micro-catchment. The runoff results achieved from these SWMM models better reproduced the hydrologic and hydraulic behavior of the study area (with RMSE of 2.51) by considering detailed catchment characteristics compared to those obtained from all the other empirical models.

Analyzing the Impacts of Sewer Type and Spatial Distribution of LID Facilities on Urban Runoff and Non-Point Source Pollution Using the Storm Water Management Model (SWMM)

The negative changes in the hydrological cycle are increasing due to climate change and urbanization, resulting in deterioration of water quality and environmental issues. Although Low-Impact Development (LID) techniques studies have been conducted to solve this problem, the spatial distribution of LID facilities and sewer types has received less attention. In this study, it is proposed to analyze the effects of sewer type, the spatial distribution of LID facilities, and LID type on runoff and water quality using the Storm Water Management Model and to identify effective ways of improving the hydrological cycle and Non-Point Source (NPS) pollution associated with urbanization. As a result of the runoff reduction analysis, 68% of the rainfall was discharged at the outlet for separate sewers, 79% for combined sewers without storage tank, and 49% for combined sewers with storage tank. The LID scenario results showed the distributed LID application method has higher reduction efficiency of runoff and NPS pollution than the intensive application method. Moreover, intensive application of LID in downstream areas resulted in higher runoff reduction efficiency than the application of LID in upstream areas. It will be used not only in the hydrological cycle plan but also in NPS pollution management.

Catchment scale effects of low impact development implementation scenarios at different urbanization densities

• The study quantified the increase of catchment runoff induced by urbanization and climate change using the SWMM model. • The study quantified the impact of different implementation strategies of low impact development (LID) on runoff mitigation. • The most sensitive parameter of SWMM catchment model were the baseflow of drainage pipes, the depression storage of pervious areas and the hydraulic conductivity. • Intense urbanization scenario (90%) resulted in increased peak drainage discharge of 100% and the total volume outflow by 20%. • Implementing LID measures at the downstream subcatchments achieved the highest peak and flooding reduction at the catchment’s outlet, while placing LID measures at the upper parts of the catchment reduces flooding at downstream manholes. Climate change and urbanization put stress on urban stormwater systems, triggering hydraulic overloading and urban flooding increase. Low Impact Development (LID) techniques have a high potential to mitigate their impacts. This study investigates the consequences of climate change and urbanization on the urban runoff in the Risvollan catchment in Trondheim, Norway, and the effects of LID implementation and the influence of LID spatial distributions on their performance. A SWMM model of Risvollan was implemented, along with different scenarios of urbanization and climate change. The performance of various spatial distributions of LID infrastructures in the catchment was investigated, using the outflow volume and the peak runoff at the outfall as indicators. The rainfall event-based simulation results confirmed the negative effects of urbanization and climate change on urban runoff. These effects were partially mitigated by a homogenous LID implementation. The different spatial distributions of LID had little impact on volume reduction but targeting the most downstream zones of the model was more efficient in reducing the peaks at the catchment’s outlet. These findings confirm that the spatial configuration of LID might be a determinant parameter towards an efficient design of LID infrastructure in urban settings, depending on the local stakes and criteria of urban water management.

Analysis of urban waterlogging causes and LID techniques

Global climate has been changing a lot in the past decades. Also extreme weather is more frequent. It results that severe urban waterlogging events happened in more and more region around the world in resent years. It killed so much people and caused tremendous poverty damage on different countries. More attention was paid on causes of urban waterlogging by many researchers. Urban waterlogging is caused by two main factors, meteorological and geological factor and urbanization factors. This review firstly analyzes the factors caused urban waterlogging, which contains meteorological and geological factor and urbanization factor. For meteorological and geological factor, global climate change have been causing more extreme precipitation events. It becomes a great challenge for urban drainage system. Also, people ignored the state of underlying surface, river portion and water storage capacity in urbanization. Those factors caused surface infiltration reducing, runoff increasing and water storage capacity reduction. Therefore, it exacerbates urban waterlogging. In order to solve urban waterlogging, many researches figured out a variety of Low Impact Development techniques (LID). Those techniques were divided into two types: infiltration-based technique and retention-based technique. For the infiltration-based technique, it aims to help city recharging subsurface flow and groundwater. For the retention-based technique, it is an approach that retain rainwater to reduce outflow. Comparing to retention-based technique, infiltration-based technique requires more fund and combination of techniques, but it is more sustainable than retention-based technique. Moreover, the review believe the implementation of the combination with two techniques would solve urban waterlogging more effectively in future. However, there still are some challenges people need to overcome, which contains requirement of substantial funding and unknown costs of maintenance, lack of performance data, and lack of understanding and close cooperation. This review also expects to reduce loss and damage loss of urban waterlogging as far as possible and to achieve combination a variety of those techniques to solve urban waterlogging in future.

Multi-criteria Decision-making Approach for Characterizing the Best Low Impact Development (LID) Techniques for Stormwater Management

Low impact development (LID) techniques are known as a novel stormwater management approach designed to mitigate the adverse effects of stormwater runoff and nonpoint source pollution. This study proposes a methodology for selecting the best LIDs based on multi-criteria decision analysis (MCDA) while incorporating different stakeholder priorities. The proposed methodology comprises analysis of alternatives, stakeholder analysis, and application of the MCDA methods. The results show that most LID techniques received ratings of more than three from the Weighted Average Method (WAM; performing well) other than green roofs and constructed filters, and no techniques averaged lower than 2.29 out of five. There is a general consensus on how vegetated filter strips and infiltration practices would perform, while there is little consensus on bioretention, level spreaders, and porous pavements. The ratings show that the majority of stakeholders thought most LIDs would perform well (a rating of more than three). The findings of this study provide an initial insight into how to support effective and widespread LID implementation for all decision-makers such as planners, designers, engineers, and stormwater managers.

Runoff Reduction Effects at Installation of LID Facilities under Different Climate Change Scenarios

In order to prepare for floods and droughts that occur as a result of climate change, various studies in water-related fields are being carried out in various countries around the world. Among them, special attention is being paid to the low-impact development (LID) technique. This study measured the annual maximum daily rainfall data from 2019 to 2100 by climate change scenario, which is the annual maximum daily rainfall series observed for rainfall stations, and tested the hydrological data using statistical analysis. After determining whether the data could be analyzed, the probability distribution was selected, and the parameters of the selected probability distribution were calculated using the L-moment method for each rainfall station. The probabilities of rainfall data were derived using GEV distribution, and the United States Environmental Protection Agency Storm Water Management Model (SWMM), a runoff simulation program, was used to compare and analyze the runoff reduction rate before and after the installation of a permeable pavement as an LID facility. The results of the analysis showed that representative concentration pathway (RCP) 4.5 and RCP 8.5 had the effect of reducing the runoff for more than 100 years at a 30% reduction rate compared with before installation.

INVESTIGATION ON HYDROLOGIC PERFORMANCE OF PERVIOUS CONCRETE PAVEMENT BY FINITE ELEMENT ANALYSIS

Pervious concrete pavement has been used widely as an effective practice for water management in low-impact development techniques. The hydrologic performance of pervious concrete pavement depends significantlyon the rainfall intensity and the designed slope. This study assessed the hydrologic performance of pervious concrete pavement by evaluating the time for surface ponding via finite element analysis. A series of simulations were carried out to explore the relationship between hydrologic performance and pervious concrete pavement by the Hydrus 2D program. The research’s results showed that as the slope increased, the time of surface ponding also increased. The data indicated that the slope variable had a low impact on the water level in pervious concrete pavement under a constant rainfall intensity. Observation of the effect of rainfall intensity showed that when the rainfall intensity increased twofold, the time for surface ponding dropped about two times. Furthermore, when surface ponding appeared, pervious concrete pavement at higher rainfall intensity had lower water content. The rainfall intensity also significantly affects the hydrologicperformance of the pervious concrete pavement. This study only assessed the hydrologic performance by using the time for surface ponding via finite element analysis. Further experimental studies should be conducted to examine the relationship of other factors to the hydrologic performance of pervious concrete pavement.

Percepção dos cidadãos sobre o manejo de águas pluviais e o uso de microrreservatórios em Belo Horizonte/MG

ABSTRACT To mitigate urbanization impacts on the hydrological cycle, Low Impact Development techniques, especially On-site Stormwater Detention - OSD, are applied worldwide. Besides their frequent use, the public knowledge about these techniques and stormwater management is insufficient, particularly in Latin America. Public comprehension about stormwater management and LID techniques lead to more acceptance and engagement. In this sense, the aim of this article is to present the results of interviews about local’s perception on stormwater management in Belo Horizonte/Brazil. The results indicate that males and respondents older than 40 years old have more knowledge about stormwater management, as well as higher socioeconomic interviewees. Although the use of OSD is positively perceived, a greater knowledge on urban stormwater does not lead to a greater willingness to co-participate in the stormwater management. Our results provide an overview of city inhabitants’ perception of municipal stormwater management and have great potential to help managers.

Tensile Strength and Dynamic Modulus of Pervious Polymer Concrete with Freezing and Thawing Cycles

The expansion of impervious areas owing to urbanization has adverse effects on water circulation. The application of low-impact development techniques to solve these problems is gaining popularity. Among others, Permeable pavements are the most widely employed low-impact development techniques. In this study, the dynamic modulus and tensile strength of pervious polymer concrete pavement were evaluated before and after freezing-thawing cycles. A tensile strength test, performed to check the soundness of the pervious polymer concrete, yielded a tensile strength and tensile strength ratio of 0.66 to 0.96 MPa, and 72 to 83%, respectively. The ultrasonic pulse velocity was measured to determine the dynamic modulus according to the freezing-thawing cycles. When 300 freezing-thawing cycles were performed, the dynamic modulus was analyzed to drop to a level of 77~85% of the initial value. The standards for freezing and thawing tests of pervious concrete have not yet been established. It is necessary to develop test standards for freezing-thawing resistance of pervious concretes considering climate change.

The Application of Low Impact Development Facility Chain on Storm Rainfall Control: A Case Study in Shenzhen, China

In recent decades, low impact development (LID) has become an increasingly important concern as a state-of-the-art stormwater management mode to treat urban flood, preferable to conventional urban drainage systems. However, the effects of the combined use of different LID facilities on urban flooding have not been fully investigated under different rainfall characteristics. In this study, a residential, neighborhood-scale catchment in Shenzhen City, southern China was selected as a case study, where the effects of four LID techniques (bio-retention, bio-swale, rain garden and pervious pavement) with different connection patterns (cascaded, semi-cascaded and paralleled) on runoff reduction efficiency were analyzed by the storm water management model (SWMM), promoted by the U.S. EPA. Three kinds of designed storm events with different return periods, durations and time-to-peak ratios were forced to simulate the flood for holistic assessment of the LID connection patterns. The effects were measured by the runoff coefficient of the whole storm–runoff process and the peak runoff volume. The results obtained indicate that the cascaded connect LID chain can more effectively reduce the runoff than that in the paralleled connect LID chain under different storms. The performances of the LID chains in modeling flood process in SWMM indicate that the runoff coefficient and the peak runoff volume increase with the increase in the rain return periods and the decrease in rain duration. Additionally, the move backward of the peak rain intensity to the end of the storm event slightly affects the peak runoff volume obviously while gives slight influence on the total runoff volume. This study provides an insight into the performance of LID chain designs under different rainfall characteristics, which is essential for effective urban flood management.

Urban Stormwater Management by Optimizing Low Impact Development Techniques and Integration of SWMM and SUSTAIN Models

توسعه‌ سریع و ناپایدار شهر‌ها منجر به تغییر خصوصیات هیدرولوژیکی حوضه‌ها شده و ریسک‌ وقوع آب‌گرفتگی ناشی از رواناب‌های شهری را افزایش داده است. یکی از راه‌حل‌های به‌کار گرفته شده برای کنترل کمی و کیفی رواناب‌های شهری، رویکرد‌های مبتنی بر زیرساخت‌های سبز و روش‌های توسعه کم‌اثر است که توجه پژوهشگران زیادی را به خود جلب کرده است. در این پژوهش، از مدل SWMM به‌منظور شبیه‌سازی فرایند بارش‌ رواناب در ناحیه یک منطقه 11 شهرداری تهران استفاده شد. 6 سناریو شامل ترکیبات مختلفی از انواع LID شامل بام سبز، مخزن باران، سلول نگهداشت‌زیستی، معابر نفوذپذیر، جوی‌ باغچه و حوضچه‌ نفوذ در نظر گرفته شد. سپس مدل SUSTAIN به‌منظور ارزیابی عملکرد هر سناریو به‌کار گرفته شد. در گام بعد پاسخ‌های بهینه از طریق الگوریتم بهینه‌سازی NSGA-II به‌دست آمد و برای هر سناریو یک منحنی پارتوی هزینه-عملکرد ارائه شد. نتایج نشان داد پاسخ‌های منتخب پیاده‌سازی سناریوهای 1 تا 6 به‌ترتیب حجم رواناب را به میزان 53، 4، 66، 72، 31 و 34 درصد کاهش دادند. سناریوی 4 با ترکیبی از مخازن باران، معابر نفوذپذیر و جوی ‌باغچه با 72 درصد و هزینه 2/12 میلیون دلار، بهینه‌ترین عملکرد را نسبت به پاسخ‌های متناظر از سناریو‌های دیگر نشان داد و سناریوی 6 نیز با 34 درصد کاهش حجم رواناب و هزینه 1/7 میلیون‌دلار در رتبه بعدی قرار گرفت. به‌کارگیری تلفیقی مدل‌های SUSTAIN و SWMM کمک کرد تا علاوه بر عملکرد فنی، هزینه و عملکرد هر سناریو ارزیابی و امکان بهینه‌سازی آن فراهم شد. نتایج به‌دست آمده از این پژوهش می‌تواند مدیران شهری و تصمیم‌گیرندگان را در طراحی، تخمین عملکرد و هزینه‌های اجرایی سناریو‌های LID یاری کند.

An Effectiveness Study on the Use of Different Types of LID for Water Cycle Recovery in a Small Catchment

Low-Impact Development (LID) is alleviating the water cycle problems that arise from an increasing impervious surface area caused by urbanization. However, there is insufficient research on the application and analyses of LID techniques that are used for studying the management goals for water cycle restoration. The present study applied various LID techniques, utilizing the stormwater management model (SWMM) in the Naju-Noan Waterfront Zone Construction Project and studying its effects, aiming to restore the runoff that had increased due to urbanization to its pre-development state. The five LID techniques used in the analysis were permeable pavements, bioswales, rainwater gardens, green roofs, and planter boxes, which took up 36.2% of the total area. Our analysis showed that development increased the runoff rate from 39.4% to 62.4%, and LID reduced it to 34.7%. Furthermore, development increased the peak flow from 0.77 m³/s to 1.08 m³/s, and the application of LID reduced it to 0.78 m³/s. An effective reduction in the runoff and peak flow was shown in every recurrence period that was tested, and the bioretention cell type of LID showed the best effectiveness per unit area compared with permeable pavements and green roofs.