Inlet Reservoir Research Articles

Step emulsification for monodisperse droplet creation using a connection-free PDMS microchip

Microfluidic technology for generating monodisperse droplets has significantly advanced various scientific and industrial applications. However, reliance on complex infrastructure, such as external pumps and intricate connections, limits its widespread adoption. In this study, we focused on passive droplet formation through step emulsification (SE) using a connection-free polydimethylsiloxane (PDMS) microchip. Our microchip design enabled droplet formation without the need for external pumps for active flow control, instead utilizing the pressure differential created between inlet reservoirs and a shared sealed-outlet space when degassed PDMS was exposed to atmospheric pressure. We began with a simple design and through progressive refinement of the microchip geometry, we achieved a more advanced design that facilitated detailed analysis of droplet formation dynamics. This design allowed for real-time observation of the droplet formation process, including time-dependent variations in droplet formation rate and the associated gentle changes in droplet size, which were intrinsic characteristics of connection-free PDMS microchips. Experiments demonstrated that a triangular nozzle design significantly improved droplet size uniformity, with a coefficient of variation in droplet diameter below 2 % under optimal conditions. These results highlighted the potential of connection-free SE microchips for generating highly uniform droplets in a simplified and efficient manner.

Erosion under drawdown flushing with the SPH method

This study investigates the effects of drawdown flushing in hydraulic structures on sediment transport and morphological changes within and around reservoirs. Utilizing the Smoothed Particle Hydrodynamics (SPH) method, the research focuses on local erosion induced by drawdown flushing and examines the interaction between water and sediment. To validate sediment behavior, we analyzed a granular dam-break model using three rheological models: Herschel-Bulkley (H–B), Bingham, and μ(I). Two drawdown flushing scenarios are explored, considering mobile bed conditions at the reservoir's inlet and outlet. The study area is categorized into three zones: water, sediment, and the interface between water and sediment, with the μ(I) rheological model applied to the sediment portion. Within the interaction zone of sediment and water, the Shields parameter is defined based on Julien's relations to determine the yield stress of sediments. This value is then incorporated into the H–B model for sediment in this specific zone. Additionally, the drag force is introduced into the momentum equation within this zone. The study's findings are rigorously validated against existing numerical and experimental studies, affirming the credibility of the modeling approach. This research provides valuable insights into the complex dynamics of sediment transport during drawdown flushing in hydraulic structures.

Developing a predictive model for low-temperature Laval nozzles with applications in chemical kinetics

Laval nozzles are used in the CRESU (“Cinétique de Réaction en Écoulement Supersonique Uniforme”) method to generate a collimated low temperature (5–200 K), low pressure (30–500 Pa), high Mach number (1 < M < 20) supersonic jet. Laval nozzles have been designed using the Method of Characteristics (MOC) since the development of CRESU, which is an analytical method that assumes inviscid, isentropic flow, and is routinely used to design nozzle profiles for a particular gas and temperature with a uniform shock free exit. This study aims to provide a robust computational framework to overcome the limitations of the MOC while also providing recommendations on the numerical model setup required to model a low-temperature supersonic jet. It also discusses the blockage effects when using the Pitot tube method for flow characterization, the influence of inlet turbulence and reservoir size. Numerical results are validated using two different experimental apparatuses from research groups at the University of Leeds and the University of Birmingham. Finally, a MATLAB framework was developed and has been provided as an open source toolbox to allow any user to perform computational fluid dynamics on any Laval nozzle, with the ability to change nozzle geometry, operating conditions and bath gas. The toolbox has been rigorously tested against many benchmark cases, which shows that steady-state Reynolds-averaged Navier–Stokes with the k-omega-shear stress transport turbulence model can be used to accurately predict global quantities, such as average temperature in the stable region of the supersonic jet.

Study on hydraulic characteristics of two-direction flow at the inlet/outlet of a large pumped storage station

Abstract The inlet/outlet is one of the most important parts of a pumped storage power station. Improper designs will cause problems such as suction vortex and increased head loss, which will affect the operation efficiency of the power station. This paper takes the inlet/outlet of a pumped storage power station in Zhejiang Province as an example for research. The upper reservoir inlet/outlet takes itself and the surrounding terrain, gully, and dam as the research object, and conducts physical model tests; the lower reservoir inlet and outlet take itself and the surrounding stone factory and other mountain terrain as the research object, and conduct numerical simulation studies. On this basis, the rationality of the scheme is explored and the optimization scheme is found, which can be used as a reference for similar engineering designers.

Thin-airfoil aerodynamics in a rarefied gas wind tunnel: A theoretical study

We study the steady aerodynamic field and loadings about a thin flat plate placed in a wind tunnel under non-continuum conditions. Considering a two-dimensional straight tunnel configuration, the flow is driven by either density or temperature differences between the inlet and outlet tunnel reservoirs, producing a pressure gradient across the channel. Focusing on highly rarefied conditions, we derive a semi-analytic description for the gas flow field in the free-molecular limit for diffuse- and specular-wall configurations. The solution is valid at arbitrary differences between the inlet and outlet reservoirs as well as plate angles of attack α. The results are compared with direct simulation Monte Carlo calculations, indicating that the free-molecular description is valid through O(1) plate-size-based Knudsen numbers. The aerodynamic lift and drag forces are evaluated and their variations with α, reservoir conditions, and tunnel size are analyzed. At a fixed pressure ratio between the outlet and inlet reservoirs, the density-driven flow generates higher aerodynamic loads compared with its counterpart temperature-driven configuration, in line with the associated larger mass flow rate in the former. The results are discussed in light of the existing rarefied-gas description of the free-stream (non-confined) problem.

Quantitative measurement of acute myocardial infarction cardiac biomarkers by “All-in-One” immune microfluidic chip for early diagnosis of myocardial infarction

Acute myocardial infarction (AMI) is a life-threatening condition with a narrow treatment window, necessitating rapid and accurate diagnostic methods. We present an “all-in-one” convenient and rapid immunoassay system that combines microfluidic technology with a colloidal gold immunoassay. A degassing-driven chip replaces a bulky external pump, resulting in a user-friendly and easy-to-operate immunoassay system. The chip comprises four units: an inlet reservoir, an immunoreaction channel, a waste pool, and an immunocomplex collection chamber, allowing single-channel flow for rapid and accurate AMI biomarker detection. In this study, we focused on cardiac troponin I (cTnI). With a minimal sample of just 4 μL and a total detection time of under 3 min, the chip enabled a quantitative visual analysis of cTnI concentration within a range of 0.5 ∼ 60.0 ng mL−1. This all-in-one integrated microfluidic chip with colloidal gold immunoassay offers a promising solution for rapid AMI diagnosis. The system's portability, small sample requirement, and quantitative visual detection capabilities make it a valuable tool for AMI diagnostics.

Investigating heat transmission in a wellbore for Low-Temperature, Open-Loop geothermal systems

Heat transfer processes in geothermal wellbores are an essential component to overall system performance, but can be overlooked in subsurface modelling studies that tend to focus on reservoir response. This study addresses heat transfer in the wellbore through a comprehensive modelling study of 10 different parameters on OpenGeoSys software designed to evaluate heat losses during open-loop production conditions for typical low-temperature (<100 °C) single phase geothermal systems. Models were set-up to focus on wellbore effects only, using a single production well with constant fluid inlet temperature boundary condition. Results indicate that under base case conditions for a 2-km deep well surrounded by rock formations with a thermal conductivity of 2.5 W/(m.K) and bottom-hole temperature of 60 °C, the difference in inlet (reservoir) and production (wellhead) temperature at the end of a 40-year production period is 2.06 °C. This corresponds to minimum heat losses into the surrounding formations of −63.3 W/m, which is ∼ 7 % of the thermal power recorded at the wellhead (assuming a rejection temperature of 30 °C) and a 3.4 % difference to bottom-hole temperature. These losses in heat can be significant, particularly when in combination with surface losses through the heat exchanger or in the reservoir through thermal breakthrough. Wellbore insulation can reduce losses, but it would appear this only impacts the short-term. Wellbore performance can also be improved, with heat losses minimized, when developing wells above the reservoir interval in low thermal conductivity rock with high geothermal gradients.

Modeling the total outflow of reservoirs using Wavelet-developed approaches: a case study of the Mahabad Dam reservoir, Iran

Abstract Lack of water reserves in artificial reservoirs poses serious challenges in meeting various human requirements, especially during periods of water scarcity. In the current research, the Total Outflow (TO) of the Mahabad Dam reservoir has been estimated under six scenarios including the Monthly Cumulative Rainfall (MCR), Snow Water Equivalent (SWE), Stream Flow (SF), Mean Temperature (T), Pan Evaporation (Ep), Sediment Flushing Gate Outlet (SFGO), Penstock Outflow (PO), Evaporation Losses (EL), Cumulative Non-Scheduled Discharge (CNSD), Live Storage Volume (LSV), Water Surface Area (WSA), Monthly Water Level (MWL), Total Allocated Water (TAW), and Generated Power (GP) variables for the 2001–2021 period. Estimation of TO is accomplished via individual and wavelet-developed (W-developed) data-mining approaches, including Artificial Neural Networks (ANNs), wavelet-ANNs (WANNs), adaptive neuro-fuzzy inference system (ANFIS), wavelet-ANFIS (WANFIS), Gene Expression Programming (GEP), and wavelet-GEP (WGEP). The obtained values of RMSE for WGEP1–WGEP6 models account for 5.917, 2.319, 4.289, 8.329, 10.713, and 9.789 million cubic meters (MCM), respectively, based on the following scenarios: reservoir inlet elements, reservoir outlet elements, consumption, storage characteristic, climate, and energy. This research revealed that combining the wavelet theory (WT) with individual models can be a powerful method to improve the modeling performance in the TO estimation.

Fluid dynamic design for mitigating undesired cell effects and its application to testis cell response testing to endocrine disruptors

Microfluidic devices have emerged as powerful tools for cell-based experiments, offering a controlled microenvironment that mimic the conditions within the body. Numerous cell experiment studies have successfully utilized microfluidic channels to achieve various new scientific discoveries. However, it has been often overlooked that undesired and unnoticed propagation of cellular molecules in such bio-microfluidic channel systems can have a negative impact on the experimental results. Thus, more careful designing is required to minimize such unwanted issues through deeper understanding and careful control of chemically and physically predominant factors at the microscopic scale. In this paper, we introduce a new approach to improve microfluidic channel design, specifically targeting the mitigation of the aforementioned challenges. To minimize the occurrence of undesired cell positioning upstream from the main test section where a concentration gradient field locates, an additional narrow port structure was devised between the microfluidic upstream channel and each inlet reservoir. This port also functioned as a passive lock that hold the flow at rest via fluid-air surface tension, which facilitated manual movement of the device even when cell attachment was not achieved completely. To demonstrate the practicability of the system, we conducted experiments and diffusion simulations on the effect of endocrine disruptors on germ cells. To this end, a bisphenol-A (BPA) concentration gradient was generated in the main channel of the system at BPA concentrations ranging from 120.8 μM to 79.3 μM, and the proliferation of GC-1 cells in the BPA gradient environment was quantitatively evaluated. The features and concepts of the introduced design is to minimize unexpected and ignored error sources, which will be one of the issues to be considered in the development of microfluidic systems to explore extremely delicate cellular phenomena.

Determination of heavy metals and rare earth elements in sediment and river water of the Citarum Watershed

Citarum River and its tributary rivers flows through Bandung Regency, with the watershed area about 6080 km2. These rivers play important role for local people in various field. Unfortunately, the anthropogenic activities in Citarum watershed have caused some environmental problems such as erosion, sedimentation, and water quality deterioration. Many various elements and heavy metals enter into the river from industrial waste, domestic waste, and some lithogenic materials where they will be distributed to aquatic ecosystem components such as sediment and aquatic biota. The aim of this research is to determine the distribution of heavy metals and rare earth elements in water and sediment river in Citarum River and its tributary river. The heavy metals and rare earth elements were measured using neutron activation analysis technique that can determine many elements simultaneously. The samples were collected from 10 sampling stations, from Situ Cisanti (upper segment) to Saguling Reservoir inlet, in March 2022. The result indicated that there were 13 elements detected in river water that consist of Na, K, Ca, Al, Mg, Ti, Co, Zn, Rb, Rb, Sb, Cs, La, V. In river sediment, 25 elements were detected that consist of 9 major elements (Na, K, Ca, Fe, Al, Mg, Ti, V, Mn), 10 minor elements (Co, Zn, Rb, Sb, Cs, Ba, Ta, Cs, Th, U, Hf) and 6 rare earth elements (La, Sc, Ce, Sm, Eu, Yb).

Chlorophyll-a prediction in tropical reservoirs as a function of hydroclimatic variability and water quality.

The study goal was to determine spatiotemporal variations in chlorophyll-a (Chl-a) concentration using models that combine hydroclimatic and nutrient variables in 150 tropical reservoirs in Brazil. The investigation of seasonal variability indicated that Chl-a varied in response to changes in total nitrogen (TN), total phosphorus (TP), volume (V), and daily precipitation (P). Therefore, an empirical model for Chl-a prediction based on the product of TN, TP, and normalized functions of V and P was proposed, but their individual exponents as well as a general multiplicative factor were adjusted by linear regression for each reservoir. The fitted relationships were capable of representing algal temporal dynamics and blooms, with an average coefficient of determination of R2 = 0.70. The results revealed that nutrients yielded better predictability of Chl-a than hydroclimatic variables. Chl-a blooms presented seasonal and interannual variability, being more frequent in periods of high precipitation and low volume. The equations demonstrate different Chl-a responses to the parameters. In general, Chl-a was positively related to TN and/or TP. However, in some cases (22%), high nutrient concentrations reduced Chl-a, which was attributed to limited phytoplankton growth driven by light deficiency due to increased turbidity. In 49% of the models, precipitation intensified Chl-a levels, which was related to increases in the nutrient concentration from external sources in rural watersheds. Contrastingly, 51% of the reservoirs faced a decrease in Chl-a with precipitation, which can be explained by the opposite effect of dilution of nutrient concentration at the reservoir inlet in urban watersheds. In terms of volume, in 67% of the reservoirs, water level reduction promoted an increase in Chl-a as a response to higher nutrient concentration. In the other cases, Chl-a decreased with lower water levels due to wind-induced destratification of the water column, which potentially decreased the internal nutrient release from bottom sediment. Finally, applying the model to the two largest studied reservoirs showed greater sensitivity of Chl-a to changes in water use classes regarding variations in TN, followed by TP, V, and P.

Integrative Magneto-Microfluidic Separation of Immune Cells Facilitates Clinical Functional Assays.

Accurately analyzing the functional activities of natural killer (NK) cells in clinical diagnosis remains challenging due to their coupling with other immune effectors. To address this, an integrated immune cell separator is required, which necessitates a streamlined sample preparation workflow including immunological cell isolation, removal of excess red blood cells (RBCs), and buffer exchange for downstream analysis. Here, a self-powered integrated magneto-microfluidic cell separation (SMS) chip is presented, which outputs high-purity target immune cells by simply inputting whole blood. The SMS chip intensifies the magnetic field gradient using an iron sphere-filled inlet reservoir for high-performance immuno-magnetic cell selection and separates target cells size-selectively using a microfluidic lattice for RBC removal and buffer exchange. In addition, the chip incorporates self-powered microfluidic pumping through a degassed polydimethylsiloxane chip, enabling the rapid isolation of NK cells at the place of blood collection within 40min. This chip is used to isolate NK cells from whole blood samples of hepatocellular cancer patients and healthy volunteers and examined their functional activities to identify potential abnormalities in NK cell function. The SMS chip is simple to use, rapid to sort, and requires small blood volumes, thus facilitating the use of immune cell subtypes for cell-based diagnosis.

Modelagem da qualidade da água em um reservatório tropical usando CE-QUAL-W2: lidando com a escassez de dados, poluição urbana e sazonalidade hidroclimática

ABSTRACT This study applies a 2-D hydrodynamic model (CE-QUAL-W2) for simulating water quality dynamics in a tropical reservoir located in Fortaleza, Ceará, Brazil. While rainfall concentrates basically in the first semester, this reservoir receives untreated sewage from an urban catchment throughout the year. To deal with data scarcity, model simplifications are justified and several adjustments are carried out, so that only the parameters temperature (T), dissolved oxygen (DO), chlorophyll a (Chla) and phosphate (PO4) are kept in the modeling process. Additionally, different assumptions are performed regarding the time-evolution of reservoir inlet concentrations: constant values, step and linear variations. The results indicate that the simplified model can predict well the seasonal variations of T, DO, Chla and PO4. The best fitting between model results and measurements are obtained with the assumption of linear variation in inlet concentrations, followed by the assumptions of constant values and step variation. Moreover, the results reveal that while PO4 presents a complete mixing behavior with a clear increase in concentration from the wet to the dry season, T, DO and Chla show an alternating stratification-destratification patter during the day-night but without relevant variations throughout the year. Model simulations of different scenarios also indicate a significant reduction in Chla concentration in the second semester, but external load reduction has a stronger impact on model outputs than hydroclimatic variability. The modeling approach developed in the present study is proposed as a simple way to cope with data scarcity, urban pollution and hydroclimatic seasonality in tropical reservoirs.

Quantifying the Permeability Enhancement from Blast-Induced Microfractures in Porphyry Rocks Using a Cumulant Lattice Boltzmann Method

The permeability of rocks is important in a range of geoscientific applications, including hbox {CO}_{2} sequestration, geothermal energy extraction, and in situ mineral recovery. This work presents an investigation of the change in permeability in porphyry rock samples due to blast-induced fracturing. Two samples were analysed before and after exposure to stress waves induced by the detonation of an explosive charge. Micro-computed tomography was used to image the interior of the samples at a pixel resolution of 10.3,mu m. The images were segmented into void, matrix, and grain to help quantify the differences in the rock samples. Following this, they were binarised as void or solid and the cumulant lattice Boltzmann method (LBM) was applied to simulate the flow of fluid through the connected void space. A correction required with the use of inlet and outlet reservoirs in computational permeability assessment was also proposed. Interrogation of the steady-state flow field allowed the pre- and post-loading permeability to be extracted. Conclusions were then drawn as to the effectiveness of blasting for enhancing fluid accessibility via the generation of microfractures in the rock matrix within the vicinity of a detonated charge. This paper makes contributions in three fundamental areas relating to the numerical assessment of permeability and the enhancement of fluid accessibility in low-porosity rocks. Firstly, a correction factor was proposed to account for the reservoirs commonly imposed on digitised rock samples when investigating sample permeability through numerical methods. Secondly, it validates the benefits of the LBM in handling complex geometries that would be intractable with conventional computational fluid dynamics methods that require body-fitted meshing. This is done with a novel implementation of the cumulant LBM in the open-source TCLB code. Finally, the improvement in fluid accessibility in low-permeability rock samples was shown through the assessment of multiple regions within two blasted samples. It was found that the blast-induced loading can generate extended microfractures that results in multiple orders of magnitude of permeability enhancement if the target rock possesses existing weaknesses and/or mineralisation.

Determination of water quality for irrigation at the entrance of Radoniqi accumulation with physicochemical and bacteriological parameters for the period of spring 2021

Water quality research for irrigation at the inlet of Radoniqi reservoir with physicochemical, heavy metals and bacteriological parameters was conducted in the spring quarter period 2021, focusing on two sampling points: at the entrance of the derivation canal (Lumbardhi River of Deçan) and at the exit of derivative canal (near the Lake) as the main supply point. In order to know the degree of its quality, the identification of polluting sources has been performed, which in turn will enable the necessary steps to be taken by the management of RWC ‘Gjakova’ for their isolation. Also, to complete the study, research was done on heavy metals and other nutrients, in all sampling sites, and especially where there are significant sources of surface water pollution, as a result of human activity and discharge of untreated urban waters. So, the focus or purpose of the research is to reflect the situation as realistically as possible and this was done by determining the bacteria by&#x0D; the membrane filter method by counting the colonies in Petri dishes with VRB-agar, M-Endo Agar Less, CCA.

The Physicochemical Properties of Deposited Sediments at the Maruba Dam Reservoir Inlet, Machakos County, Kenya

Energy and water are the two most important natural resources in the globe. In this regard, dams and reservoirs are the critical hydraulic structures that store water and, above all, provide energy required by humanity. However, water storage and the provision of energy by reservoirs and dams have been disrupted by significant environmental changes taking place in the catchment areas and the reservoir environment. These disruptions are brought about by climatic parameters and sediment transport by different eroding agents. One such environmental problem is soil erosion, whose effect is reservoir sedimentation. Consequently, a part of the transported sediment is deposited at the catchment outlet, which serves as the reservoir inlet. This study was carried out to establish the physicochemical characteristics of the deposited sediment at the reservoir inlet. The following parameters were analyzed: particle size distribution, organic matter content, bulk density, porosity, electrical conductivity, penetration resistance, hydraulic conductivity, pH, and nutrients (nitrogen, phosphorous, and potassium) using standard laboratory procedures. The study established that the deposited sediments were predominantly sand particles with mean values of 50.60% and 58.60% for the surface (0–10 cm) or sub-surface horizons (10–20 cm), respectively. The average values for sediment pH, organic matter, porosity, bulk density, electrical conductivity, penetration resistance, hydraulic conductivity, and nutrients were 6.30 and 6.61; 1.91 and 1.80%; 54.10 and 57.10%; 1.22 and 1.14 g·cm−3 for the surface and sub-surface horizons, respectively. The most variable parameters were silt content (sub-surface horizon), hydraulic conductivity, penetration resistance, electrical conductivity, nitrogen content (surface horizon), and phosphorous (surface horizon) content with CV &gt;0.35. Based on the present study results, the deposited sediments at the reservoir inlet were found to have low concentrations of nutrients and high sand proportions. Therefore, the deposited sediments appear to have great potential to reclaim the immediate barren dam environment upon enrichment and to promote sand harvesting programs for economic benefits.

Phosphorus fractionation and adsorption characteristics in drinking water reservoir inlet river sediments under human disturbance

Phosphorus fractionation and adsorption characteristics in drinking water reservoir inlet river sediments under human disturbance

ANALISA LAJU SEBARAN YIELD SEDIMEN PADA DTA WADUK SAGULING DENGAN MENGGUNAKAN PENDEKATAN USLE-GIS

&lt;p&gt;One of the issues that is still a problem in the upstream watershed, including the&lt;br /&gt;water catchment area of Saguling Reservoir, is land use change. Changes in land&lt;br /&gt;use in water catchment conservation areas into economic, industrial and residential&lt;br /&gt;areas, will cause an increase in run-off during the rainy season and sediment&lt;br /&gt;transport to the reservoir inlet, while changes in land use downstream of the&lt;br /&gt;reservoir will cause an increase in demand. Therefore, research is needed to&lt;br /&gt;determine the rate of increase in sediment yield that occurs in the watershed of the&lt;br /&gt;Saguling Reservoir. The integration of USLE and GIS allows us to determine the&lt;br /&gt;spatial distribution of parameters. Each factor in USLE is calculated using the&lt;br /&gt;existing facilities in the GIS software. The results showed that there was an&lt;br /&gt;increasing rate of sediment yield in the "Very Heavy" TBE category, while in the&lt;br /&gt;"Medium" TBE category the trend of sediment yields showed a downward trend.&lt;/p&gt;

A novel analytical model of solute transport in a layered aquifer system with mixing processes in the reservoirs.

Analytical models of solute transport have been widely used to aid the understanding of the physical and chemical processes undergone by substances introduced in a layered aquifer system. However, in previous studies, the advection component of transport was assumed to be one dimensional, while also ignoring the mixing processes that occur in the inlet and the outlet reservoirs. In this study, new sets of models describing those mixing processes are presented. Beyond that, these models were integrated into already existing models and the result is a novel analytical model of solute transport in aquifer-aquitard systems. The novel analytical solution was derived by the Laplace transform method and the finite-cosine Fourier transform method under the mobile-immobile (MIM) framework. The calculations take into account: the longitudinal and vertical dispersion, the molecular diffusion and the horizonal and vertical advection components of solute transport, as well as first-order chemical reaction, in both the aquifer and the aquitard. A finite-difference solution of the model is tested against experimental data in order to critique its reliability. Results indicate that the numerical and analytical solutions of the new model match well with experimental data. This new model outperforms the previous models in terms of interpreting experimental data. The mixing old and new water in the reservoirs during solute transport in aquifer-aquitard systems is important. Global sensitivity analysis demonstrates that the output concentration of solute in the aquifer-aquitard system is most sensitive to the volume of water in the inlet reservoir. The contribution of the molecular diffusion effect to the total mass flux of the tracer cross the aquifer-aquitard interface is much smaller than the contribution of the dispersive and advective effects.

Influences of natural salinity sources and human actions on the Shapour River salinity during the recent streamflow reduction period.

The Shapour River, with a catchment area of 4254 km2, is a major river system in southern Iran. While the upstream river flow (the upper Shapour River) is fresh, it becomes extremely salinized at the downstream confluence of the Shekastian saline tributary and the entering nearby Boushigan saline spring. Then, the river passes via the Khesht plain and finally discharges into Raeisali-Delvari storage dam which went into operation in 2009. Over the 2006-2019 period, reduced precipitation and over-utilization of freshwater resources resulted in ~ 72% streamflow reduction in the Shapour River. Due to not using the saline waters for irrigation, drinking, and industrial purposes, the ratio of saline-outflow of Shekastian tributary and Boushigan spring to fresh-outflow of upper Shapour River increased by ~ 3 times; consequently, river salinity fluctuation domain at the Khesht plain inlet dramatically increased from 2.1-4.0 dS m-1 to 3.7-26.0 dS m-1. It resulted in major economic damages to the agricultural sector of middle Shapour River. On the seasonal timescale, consecutive processes of salt accumulation during irrigation season of the Khesht plain date orchards and then salt drainage during the rainy season have adjusted salinity fluctuation domain from 3.7-26.0 dS m-1 at the plain inlet to 5.2-8.9 dS m-1 at the plain outlet. In the lower Shapour River, storage/mixing of fresh/saline inflow waters in the Raeisali-Delvari reservoir has adjusted strong river salinity fluctuation domain from 0.9-10.7 dS m-1 at the reservoir inlet to 3.6-5.5 dS m-1 at the reservoir outlet. The success of the Raeisali-Delvari reservoir for salinity adjustment is due to its suitable location on the Shapour River, by being situated downstream of all main river tributaries with natural saline/fresh sources of water.