Drainage Functions Research Articles

Nature-issues: Ecosystem restoration as a reorganiser of social–material relations

Ecosystem restoration initiatives present natures as intervention-requiring problems. However, not all stakeholders may be able to recognise and relate to the issues that motivate restoration. Instead, they may put forward alternative understandings of natures as problematic issues in need of management and collective action. Therefore, ecosystem restoration can turn generative into new forms of publics that are brought together – and drawn apart – by distinctive configurations of nature-issues. This paper analyses such a reorganisation by focusing on three restoration projects carried out in Finland. The projects sought to engage farmers in restoring agricultural streams while proposing the practice of stream restoration as an extensive ecosystem revitalisation. In the studied cases, farmers could become attentive to the potential of stream habitats to develop into viable and rich ecosystems, while their neighbours only showed interest in improving the drainage functions of streams. The restoration initiatives generated connectedness between farmers, streams habitats and the restoration projects, but also disconnectedness between natures and publics. The possibilities of the studied projects to carry out their restoration plans rested mostly on the specification of the restoration plans as a means to manage ontological differences. The findings indicate that instead of promoting ecosystem restoration as a tightly coupled practice, it can be useful to generate space for collective action that unfolds in terms of partially different natures and nature-issues.

Conceptual framework to incorporate drainage solutions in the urban open space system

Cities are increasingly dealing with challenges regarding the negative impact of rapid and mismanaged urbanization. Therefore, city planning must cope with the natural environment limitations, seeking a balance between the human activities and the well-functioning of the hydrologic cycle. This work aims to present a conceptual framework able to properly integrate the stormwater dynamics into the open spaces system in a functional way, establishing a Hydrological Interest Area, HIA, to structure urban expansion integrated into and respecting watershed natural processes. The initial step is to define a HIA, primarily consisting of open spaces that can be used for supporting urban drainage functions and to order land use in the urban expansion process. This delimitation offers the background for interpreting the watershed in three functional arches, especially covering the upstream, mid-reach and downstream areas of the basin, guiding the design of a set of flood mitigation interventions focusing on the use of Blue-Green Infrastructure. To illustrate and validate the proposed methodological framework, the design is evaluated by a flood modeling tool, using a hydrological-hydrodynamic cell-model. A case study was driven in the Bambu Watershed, a rapidly developing area in the municipality of Maricá, Rio de Janeiro, Brazil. The proposed intervention includes an urban expansion scenario for a low impact development on flood behavior alongside with four parks: an upstream park with reservoirs, two multifunctional floodable urban parks, and a park dedicated to lagoon restoration. This plan complements riverbed modifications designed to enhance water discharge. The simulation showed significant reduction of water depths with a consequent decrease in exposure of buildings and roads, especially in the most critical region of the watershed. This framework highlights the importance of a multifunctional approach in land use and serves as a robust foundation for controlling urban expansion and proposing projects.

Rainwater harvesting through roofs and stormwater harvesting through pervious pavements: A Life Cycle Assessment and decision-making comparison

Water consumption and the building sector are among the top contributors to environmental impacts worldwide. Also, sustainable practices have been constantly encouraged in both sectors to mitigate water scarcity and provide resilience to cities. Thus, studies that provide an environmental assessment and discuss the decision-making process are essential for enabling the augmentation of sustainable practices. This research aims to contribute to the discussion on sustainability by conducting a Life Cycle Assessment (LCA) of Sustainable Urban Drainage Systems (SUDS) examples. LCA is the main methodology applied to perform environmental comparisons. First, a thorough inventory was obtained from previous works with different alternatives for water management within a university building, including drainage, paving and water supply functions. The inventory contemplates alternatives using rainwater and stormwater harvesting for non-potable water supply, including pervious pavements. Such alternatives were compared with Brazil's usual water supply systems, aiming at diminishing the total environmental burden. The methodology aspects of LCA were also regarded, such as an uncertainty assessment and a quality matrix of the processes used. Midpoint and endpoint categories were also regarded with their decision-making and uncertainty analysis. The main result is the understanding of the trade-offs between the proposed systems, with a significant reduction in water stress obtained in the alternative scenarios. However, such a decrease is accompanied by a slight increase in some impact categories. Rainwater harvesting through roofs is the most environmentally friendly alternative, although the Cultural Theory parameter definition impacts on the sustainability ranking. Alternative sustainable systems for water management still need validation in terms of LCA, while decision-making for sustainable and resilient cities also requires a robust scientific basis. Thus, in conclusion, alternative systems such as SUDS were obtained to be more sustainable than conventional paving, drainage and water supply in the case study, and the understanding of different benefits found in the LCA is important to the decision-making process.

Meso-structural evolution characteristics of porous asphalt mixtures with stress-induced and their effects on environmental functions

This study aims to investigate the meso-structural evolution characteristics of porous asphalt mixtures (PAM) under stress and their effects on drainage and noise reduction environmental functions. Digital image processing technique was used to accurately identify the internal voids during uniaxial compression testing. The focus was on analyzing and simulating meso-scale differences in internal void structures before and after deformation and quantifying the evolution of these voids during the strain process. Drainage and noise reduction tests were conducted, and correlation analysis and factor screening were performed. The results indicate that in stress-induced meso-structural evolution, contact between aggregates generates force chains, and with increasing strain, the length of these chains and the number of aggregate contacts increase. Significant forces occur at the interface between aggregates and asphalt mortar. Aggregates undergo relative translational motion due to resistance to loads, resulting in compressed voids, cracks between asphalt mortar and aggregates, and gradual deterioration of the mixture structure. Additionally, the increase of strain significantly reduces the drainage and noise reduction performance of porous asphalt mixtures. The scale relationship diagram between macro- and meso-scale indicators identifies strain, void area and void sphericity as the primary influencing factors. The research findings contribute to understanding the stress transfer characteristics of PAM at the meso-structural scale, thereby enabling adjustments to grading, optimization of void structures, and enhancement of their long-term environmental functions.

Hydrotechnical and ecological principles of water resources management for a mined-out mine field

The article considers the issue of predicting and managing water resources of flooded mines based on hydrotechnical and ecological criteria. Reproduction of a natural-technogenic situation within mine fields with many unknowns regarding the condition of a rock massif and influence factors became possible through a step-by-step construction and identification of a numerical geofiltration model. Balance components of formation for a technogenic underground water mode, capacity parameters and zonal water permeability of a rock massif are estimated as a result of methodical adaptation and creation of a hydrodynamic model of two adjacent mines with a complex hydrogeological structure. A duration and speed for groundwater level restoration at different time periods, an area of underflooding and flooding on the surface is established according to predictive calculations. The inefficiency of submersible pumps use is proven when capital workings lose their drainage functions and a massif has rheological dynamics. Variants for long-term pumping of mine waters with subsequent discharge into a hydrographic network do not bring the territory into a self-draining mode. Therefore, the mode of closing mines with full restoration of underground water level in a monitoring mode with a combination of drainage reconstruction of the surface is the most acceptable.

Research on construction parameters of stone columns for liquefaction mitigation in coral reef sand areas

For loose coral reef sand with high fines content located in strong earthquake zones, it is necessary to choose stone columns as a liquefaction mitigation ground improvement method that can consider both drainage and densification functions. Taking the Tibar Bay Port project in East Timor as an example, the bottom-feed technology of vibrating stone columns was developed, and typical coral reef sand sites with different fines contents were selected as trial test areas. Experimental research was performed to study the construction parameters for onshore and offshore stone column processes. Tests showed that the vibratory process control parameters, quality acceptance standards, and control procedures proposed through research meet the anti-liquefaction requirements for both drainage and densification effectiveness. The different construction characteristics of onshore and offshore stone columns were also analyzed. Considering the particularity of underwater stone column construction, the research results can be used for stone columns reinforced grounds similar to coral sand onshore and offshore.

Research on the Influencing Factors of AUV Hovering Control in Null-Speed State

Intelligent underwater vehicles hover by way of a hovering control system. To provide design inputs and maneuver guidance, this study focused on the characteristics of intelligent underwater vehicles during hovering control with the propulsion system shut down, established a mathematical model of hovering control and determined injection and drainage functions based on optimal control theory. From analysis simulation experiments, the influence laws of control parameters, control timing and rate of injection and drainage control upon hovering control were deduced. It is proposed that, at the time of control parameter selection, the continuous injection and drainage rate at each time should be reduced as far as possible to relieve the demand on the volume of the reservoir when the requirement of depth control accuracy has been satisfied. In addition, the injection and drainage control should initiate when depth changes exceed 0.5 m. Suggestions are included on the minimum injection and drainage rate required for different initial disturbances. The proposed suggestions guide the design of hovering control systems and hovering control over intelligent underwater vehicles.

Research on Water Stability and Moisture Damage Mechanism of a Steel Slag Porous Asphalt Mixture

A steel slag porous asphalt (SSPA) mixture, as the surfacing layer of permeable asphalt pavements, not only ensures the pavement surface drainage and noise reduction functions, but also improves the comprehensive utilization of steel slag resources and the inherent protection of the ecological environment. However, compared with ordinary asphalt mixtures, SSPA is more susceptible to water damage, such as scouring and frost swelling caused by external rainwater intrusion, resulting in the deterioration of the pavement performance. Therefore, it is of good practical imperative to study the water stability and moisture damage mechanism of SSPAs. In this study, the water stability of SSPA, that was subjected to a series of time–temperature H2O-immersion schemes, was investigated using the pull-out and H2O-immersion Marshall tests, whilst the microscopic mechanism of moisture damage was studied using the scanning electron microscopy (SEM), Fourier infrared spectroscopy (FTIR), and X-ray diffraction (XRD) tests. The corresponding results showed that: (a) with the increase in the H2O immersion time, the water stability of SSPA first increased and then decreased; and (b) the water stability of SSPA was strong under medium-temperature H2O-immersion or short-term high-temperature H2O-immersion. SEM, on the other hand, showed that the transition zone spacing was closely related to the chemical adhesion mechanism between the asphalt and steel slag aggregate. Additionally, the FTIR analysis further showed that the steel slag asphalt mastic spectra had new absorption peaks at 3200~3750 cm−1, inherently indicating the existence of chemical bonding between the asphalt and steel slag, with the XRD results showing that CaSO4·2H2O had a beneficial effect on the water stability of SSPA.

Study on the Mechanical Capacity and Structural Relevance of a Flying Buttress Through the Analysis of a Particular Case

ABSTRACT A flying buttress serves an aesthetic purpose and two technical purposes. In particular, it helps to drain rainwater from the roof and also plays a structural role. The aesthetic and drainage functions can be determined visually and with the help of several bibliographical references. On the contrary, in order to assess the structural function a rigorous mechanical study must be carried out. Starting from the mechanical capacity of a flying buttress, this paper presents a method to determine its relevance and influence on the structural behaviour of the cathedral.

The correlation between nasal and paranasal sinus anatomical variations with severity of Chronic Rhino Sinusitis Based on CT Scan Examination at Dr. Zainoel Abidin Hospital Banda Aceh

Background: Chronic rhinosinusitis (CRS) is a persistent inflammation of the nasal mucosa and paranasal sinuses. Anatomical variations of the nasal and paranasal sinuses can obstruct and impair the drainage and ventilation functions of the sinus ostium, causing CRS. Objective: To determine the correlation between nasal and paranasal sinus anatomical variations with the degree of severity of CRS based on a CT scan at Dr. Zainoel Abidin Hospital. Methods: An analytic observational study with a cross-sectional design from the results of CT scans of CRS patients in the period on October 2019-october 2022. The anatomical variations assessed were the degree of deviation of the nasal septum, type of bullous turbinate, paradoxical turbinate, hypertrophy of ethmoid bullae, Haller cells, deflection of uncinate process, type of superior insertion of the uncinate process, pneumatization of the uncinate process and frontal sinus cells to the degree of CRS using the Lund Mackay score. Data were analyzed using the Chi-Square test or Fisher's exact test. Result: Analysis of 64 CT scans consisting of 128 sides of the nose found a significant relationship between anatomic variations and the degree of CRS, namely the degree of deviation of nasal septum, type of concha bullosa, ethmoid bulla hypertrophy and deflection of the uncinate process to the severity of maxillary sinusitis (p=0.023; p=0.024; p=0.039; p=0.029) and paradoxical medial concha for the severity of maxillary sinusitis, anterior and frontal ethmoiditis (p=0.018; p=0.013; p=0.000) Conclusion: Anatomical variations of the nasal and paranasal sinuses are related to the severity of CRS.

Characterization of pollutants and identification of microbial communities in the filter media of green infrastructures

Green infrastructure (GI) technologies use natural mechanisms and processes associated with microorganisms, plants, and filter media to facilitate mass circulation and energy flow in the ecosystem. Despite the numerous studies focused on the functions and pollutant treatment performance of nature-based stormwater treatment technologies, studies concerning the effects of filter media characteristics on the diversity and abundance of microorganisms in green stormwater infrastructures are still lacking. In this study, the physico-chemical characteristics of filter media and accumulated sediments in an infiltration trench (IT) and bioretention facility (BI) were investigated. Moreover, the composition and distribution of different microbial communities in GIs designed for stormwater treatment were identified. As compared with BI, higher pollutant concentrations were noted on the filter media and sediments accumulated in IT due to the higher degree of anthropogenic activities in IT's catchment area. Inorganic filter media (i.e., gravel) tend to have greater pollutant trapping efficiency due to the accumulation of sediments in the macropores. On the other hand, organic filter materials (i.e., woodchips) may serve as carbon sources for fueling microbial processes and promote better moisture retention in the facility. Proteobacteria, which constituted 38.6% to 43.0% of the total bacterial population in IT and 37.9% to 41.4% of the total bacterial population in BI, was found to be the most dominant type of bacteria in the facilities. In terms of microbial diversity, BI exhibited a higher diversity index, which is most likely due to the presence of vegetative components forming a symbiotic relationship with microbial colonies. Generally, inorganic filter media are mainly used for improving the GI technologies' drainage and infiltration functions, whereas organic filter media provide suitable growth environments for different bacterial communities involved in important biogeochemical cycles.

BIO16: Computation Fluid Dynamics Analysis of Dual Lumen VV ECMO Cannulas

Background: Venovenous extracorporeal membrane oxygenation (VV ECMO) treatment requires blood to be drained from the patient’s venous system, oxygenated in an artificial membrane, and returned. Traditionally, this has been achieved with two, single lumen cannulas (SLCs). More recently, dual lumen cannulas (DLCs) combining both drainage and return functions into a single device have become increasingly popular. Recirculation fraction, the proportion of oxygenated return blood which is directly drained out before passing through the tricuspid valve, should be low. Another key design objective for these cannulas is to minimize shear stress, as high levels increase the risk of coagulation activation (hemolysis). Whilst DLCs are thought to have superior recirculation performance compared to SLCs, this has not yet been demonstrated in a direct comparison. Furthermore, the shear stress produced by DLCs, their impact on native hemodynamics and response to changes in positioning have not been reported in adults. In this study, we aim to describe the recirculation and hemodynamic performance of DLCs. Methods: A patient-averaged model of the right atrium (RA) and the venae cavae was used to model venous flow. Two common DLCs, the Maquet Avalon Elite (Getinge) and MC3 Crescent (Medtronic) were converted into 3D models (Figure 1A.). Both were downscaled to 27Fr for our patient model. To delineate these from the off-the-shelf products we use the prefix “ds” for downscaled. Both DLCs were first positioned optimally and simulated at 2,4 and 6 L/min. Noting a high degree of similarity, insertion depth (±4cm) and rotation (±30° and ±60°) was only assessed for the dsAvalon.Figure 1. A. Downscaled (ds)Avalon and dsCrescent cannula features. B. Drainage fractions from the superior (SVC) and inferior vena cava (IVC) C. Time-averaged velocity streamlines of the high-velocity jet exiting the reinfusion port of both DLCs at 4L/min. Results: Pressure drop curves were nearly identical for the two devices. dsAvalon pressure drops agreed well with experimental data. Recirculation fraction was low for both DLCs compared to SLCs. SVC and IVC drainage adapted with ECMO flow rate to draw a greater proportion of flow from the IVC at high ECMO flow rates (Figure 1B). The reinfusion port design created a high-velocity jet of blood (Figure 1C). Consequently, time-averaged wall shear stress (TAWSS) was very high (>475 Pa) at the reinfusion port for both designs. Discussion: DLCs exhibit superior recirculation performance compared to SLCs under ideal conditions. This appears to be due to DLCs ability to drain flow from both the IVC and SVC, favoring greater IVC drainage at higher ECMO flow rates. Both designs produce a highly focused reinfusion jet which may increase risk of hemolysis and coagulation activation.

Geosynthetics in tunnels and underground structures applications

Waterproofing systems of tunnels is of crucial importance for the long-term effectiveness of the underground works and for the possible impact on the surrounding environment. In conventional tunnelling, polymeric geomembranes are nowadays used with fluid barrier function, while nonwoven geotextiles and geonets are commonly employed with mechanical protection and drainage functions. After some descriptions of the main requirements of the geosynthetics used in tunnels and underground structures, the durability aspects of the materials forming the waterproofing systems are briefly outlined.

Expansion of pipeless drainage functions for draining poorly permeable soils

Due to climate change, in the next 30-50 years, an increase in precipitation during the growing season is predicted in the Non-Chernozem zone of Russia. However, even now, traditional methods of draining poorly permeable soils in a number of cases have proved to be ineffective due to the insufficiency of operational and capital measures to accelerate the removal of surface water and the weak hydraulic connection between the arable layer and drains. The experience of operation of drainage systems in the Nonchernozem zone of Russia has shown that at large distances between channels, the removal of surface runoff is difficult. A rational solution is to reduce the distances between the conductive channels. In this case, instead of open collectors, we propose to use cavityless collectors for drainage, which do not interfere with the movement of heavy agricultural machinery. A complete analysis of the functioning of cavityless collectors has been carried out. In the part of hydrology, accounting for the increase in precipitation is discussed and a method is given for calculating the maximum average daily module of drainage flow for the early spring and summer-autumn periods. A geotechnical calculation of the settlement during the passage of a heavy general-purpose tractor of the 5th traction class K-744R1 (Kirovets) was performed. It is shown that under the design conditions, the settlements will be about 1 cm. An example of a hydraulic calculation of the reservoir with the calculation of the initial and maximum depth of the filtration flow in it is given. Hydraulic calculation is carried out according to a proven method, the theoretical foundations of which were developed by the authors in previously published articles. An important feature is that all possible filtration modes are taken into account in the hydraulic calculation: laminar, transitional and turbulent.

Development of an Urban Flood Forecast Model Using Lumped Pipe Networks

Typical urban flood simulation is conducted using physical models such as the 1D storm water analysis model and 2D inundation analysis model. Although 2D inundation analysis can predict flow velocity, inundation depth, and inundation area throughout an inundated urban area, it is difficult for it to produce a near real-time urban flood forecast for a metropolitan area such as Seoul. In this study, a physical urban flood forecast model was developed using lumped pipe networks to produce a near real-time urban inundation forecast. The dense pipe networks within a drainage basin were simplified as a single conceptual lumped pipe that has drainage and storage functions, and new pipe networks were constructed using lumped pipe networks. The model was applied to the August 2018 storm events in Seoul and showed a prediction accuracy of 0.71. The results demonstrated that the model can obviate the limitations of the near real-time operation of existing physical flood forecasting models to yield useful information for urban flood response, though showing room for improvement.

Performance analysis of proton exchange membrane fuel cells with traveling-wave flow fields based on Grey-relational theory

A traveling-wave flow field is established and investigated for the performance improvement effect of proton exchange membrane fuel cell (PEMFC). This study analyzes the influence of multiple structural parameters of traveling-wave length, wave height, wave number, and wave spacing on the flow law, mass transfer characteristics, and output performance of PEMFC, and obtains the weight coefficient of each structural parameter through the Grey-relational theory. Simulation results show that the traveling-wave flow field has excellent oxygen transport and drainage functions, and its corresponding functional structures are wave crest and wave trough respectively. Compared with the conventional flow field (CFF), the effective mass transfer coefficient (EMTC) at the BPP/GDL interface can be increased about 35.89–118%, and the drainage at the BPP/GDL interface can be increased about 0.9–2.24%, and the net power density of the PEMFC can be increased about 4.45–11.17% of the PEMFC with traveling-wave flow field. In addition, the weighting relationship of the traveling-wave structural parameters on the mass transfer performance and net power density is wave height > wave number > wave length > wave spacing.

Новые возможности терапии экссудативного среднего отита у детей

Anti-inflammatory therapy for otitis media with effusion (OME) in patients with chronic diseases of the Waldeyer's tonsillar ring is a key stage of treatment. Patients and methods. This observational study included 85 patients. Group 1 comprised 50 OME patients with grade I–II pharyngeal tonsil hypertrophy who were further divided into two subgroups: 1A (n = 30) and 1B (n = 20). Group 2 involved 35 OME patients on the second day after adenectomy; they were divided into subgroups 2A (n = 20) and 2B (n = 15). Children in subgroups 1A and 2A received standard OME therapy plus ammonium glycyrrhizinate (AG) for 30 days, whereas children in subgroups 1B and 2B received standard OME therapy alone. Results. Patients from the experimental subgroups (1A and 2A) who received AG demonstrated significantly lower VAS scores of both auditory symptoms (hearing loss and congestion/noise in the ear) and initial manifestations (rhinorrhea and nasal congestion) already by first follow-up visits compared to controls (subgroups 1B and 2B). Maximum differences were observed on day 30: the severity of symptoms in children from group 1A was 2.5 times lower than in children from subgroup 1B; patients from subgroup 2A also demonstrated a 2-fold reduction in symptom severity compared to children from subgroup 2B (p < 0.05). Tympanometry showed that 90% of patients in the experimental subgroups (1A and 2A) had complete restoration of auditory tube function by day 30, while in control subgroups 1B and 2B, the proportion of such patients was significantly lower (55% and 73%, respectively). Audiometry results suggest that complete hearing restoration by day 30 was more frequent in patients receiving AG than in controls (1A and 1B: 94% vs 70%; 2A and 2B: 100% vs 80%). Patients of the experimental subgroups were more satisfied with treatment results. Conclusion. The inclusion of AG into the treatment scheme for OME and auditory tube dysfunction after elective adenectomy increases treatment efficacy by normalizing drainage and ventilation functions of the middle ear, elimination of exudate, and ensuring hearing restoration. Key words: otitis media with effusion, children, auditory tube, Waldeyer's tonsillar ring, hearing loss, impedance audiometry, ammonium glycyrrhizinate

ТИМПАНОСТОМИЯ ПРИ ЭКССУДАТИВНОМ СРЕДНЕМ ОТИТЕ У ДЕТЕЙ

Acute and chronic otitis media remain the leading causes of conductive hearing loss. Every second child by the age of 3 years and by the age of 5 years up to 70% of children had acute otitis media. Chronic otitis media with effusion is detected during mass examinations of children aged from 2 to 7 years in 30.2% of cases. The starting point in the development of otitis media with effusion both acute and chronic forms is a violation of the ventilation and drainage functions of the auditory tube. Elimination of effusion from the tympanic cavity after nasopharynx therapy and rehabilitation of the function of the auditory tube occurs in 75% of cases. Tympanostomy is indicated where the function of the auditory tube is not restored after adenotomy or conservative treatment. Tympanostomy is widely introduced as a method of surgical treatment for otitis media with effusion both acute and chronic forms in a number of countries. However, there is no consensus on the method of intervention and further management of patients among specialists. The article provides an overview of the opinions and results of tympanostomy using in case of otitis media with effusion in children.

A New Strategy for Sponge City Construction of Urban Roads: Combining the Traditional Functions with Landscape and Drainage

Urban roads play a key role in sponge city construction, especially because of their drainage functions. However, efficient methods to enhance their drainage performance are still lacking. Here, we propose a new strategy to combine roads, green spaces, and the drainage system. Generally, by considering the organization of the runoff and the construction of the drainage system (including sponge city facilities) as the core of the strategy, the drainage and traffic functions were combined. This new strategy was implemented in a pilot study of road reconstruction conducted in Zhangjiagang, Suzhou, China. Steel slag was used in the structural layers to enhance the water permeability of the pavement and the removal of runoff pollutants. The combined effects of this system and of the ribbon biological retention zone, allowed achieving an average removal rate of suspended solids, a chemical oxygen demand, a removal of total nitrogen and total phosphorus of 71.60%, 78.35%, 63.93%, and 49.47%; in contrast, a traditional road could not perform as well. Furthermore, the volume control rate of the annual runoff met the construction requirements (70%). The results of the present study indicate that, combining the traditional basic functions of roads with those of landscape and drainage might be a promising strategy for sponge city construction of urban road.

Afforestation of Degraded Croplands as a Water-Saving Option in Irrigated Region of the Aral Sea Basin

Climate change is likely to decrease surface water availability in Central Asia, thereby necessitating land use adaptations in irrigated regions. The introduction of trees to marginally productive croplands with shallow groundwater was suggested for irrigation water-saving and improving the land’s productivity. Considering the possible trade-offs with water availability in large-scale afforestation, our study predicted the impacts on water balance components in the lower reaches of the Amudarya River to facilitate afforestation planning using the Soil and Water Assessment Tool (SWAT). The land-use scenarios used for modeling analysis considered the afforestation of 62% and 100% of marginally productive croplands under average and low irrigation water supply identified from historical land-use maps. The results indicate a dramatic decrease in the examined water balance components in all afforestation scenarios based largely on the reduced irrigation demand of trees compared to the main crops. Specifically, replacing current crops (mostly cotton) with trees on all marginal land (approximately 663 km2) in the study region with an average water availability would save 1037 mln m3 of gross irrigation input within the study region and lower the annual drainage discharge by 504 mln m3. These effects have a considerable potential to support irrigation water management and enhance drainage functions in adapting to future water supply limitations.