Iranian Water Research Journal

Abstract Extended Abstract
The set of factors including rainfall decrease, population increase, excessive use and waste of water in water supply networks has caused the world to face a serious shortage of water resources. Preventing water loss is one of the most important indicators of preserving water resources. In all sectors of water consumption (agriculture, drinking water, industry, etc.), water loss is an inevitable challenge. In urban water distribution networks, the high amount of water loss is due to their large size and multiple connections.
Chavar city located in Ilam province, Iran, is situated 15 kilometers northwest of the provincial capital. The population of this city is 10,554 people, of whom 5,831 live in the central part of Chavar city. Most of the city's distribution network pipes are made of asbestos, polyethylene pipes and even some metal pipes with small diameters. There are asbestos pipes with diameters of 50, 110, 100 and 200 mm, polyethylene pipes with diameters of 110 and 125 mm; and steel pipes with diameters of 25, 38 and 200 mm. With field surveys, the simulated water network was updated and the hydraulic analysis of the network was done by Auto CAD, GIS, Water GEMS software. According to the location of the subscribers, their consumption was allocated to the nearest pipe. In order to measure the pressure in different points of the network, oil type (glycerin) gauges were used. An ultrasonic portable flow meter was used to measure the flow rate.
In the first step of analysis of the transmission line, the flow rate was measured at the water supply well, the transmission pipeline and the two reservoirs in the transmission system. The design of the transmission line in two sections was modeled by Water GEMS software. The first part included a well to a concrete reservoir of 700 cubic meters, and the second part included a reservoir of 700 to a 1000 cubic meters. There were four pumps in this network. The PMP-1 pump belonged to the well, which had a flow rate of 56.29 liters per second and a pump head of 153.3 meters. PMP-2, PMP-3 and PMP-4 pumps were connected to the 700 cubic meter tank, which operated as two active pumps and one in standby mode during the day, and one active pump with two pumps in standby mode during the night. In the case of two active pumps, each pump had a flow rate of 38.44 liters per second and a head of 158.3 meters. The pipelines analyzed in the software showed that the first transmission line transferred a flow rate of 56.2 liters per second at a velocity of 1.79 meters per second to the 700 cubic meter reservoir. The second transmission line transferred the flow rate of 76.8 liters per second at a velocity of 1.22 meters per second for the 1000 cubic meter reservoir to the distribution network. The velocity in both pipelines was acceptable according to the range of design criteria, and the flow rate was completely consistent with the design flow rate of the pumps. The results of network simulation showed that 57% of the network nodes were in the peak consumption mode. This was due to the level difference of more than 130 meters between the reservoir and the consumer, as well as the absence of pressure reducing valves. Therefore, the pressure was outside the permissible range of 14 to 45 meters of water. Also, 73 percent of the pipelines lack the optimal velocity of 0.3 to 2.5 meters per second due to the inappropriate diameter of the pipelines. In the second simulation mode with 0.7 maximum flow rate (corresponding to the lowest amount of consumption in the coldest seasons of the year), the pressure in the nodes was improving, and 64.5% of the nodes had the optimal pressure, but the velocity remained outside the standard permissible range in 84% of the pipelines. The simulation in the transmission lines was validated by comparing the discharge field measurement using the ultrasonic flow meter and the value calculated in the software. The pressure of the network was measured at several points by the pressure gauge. Then these values were compared with the pressures obtained from the simulation in the lowest consumption mode. The results indicated that there was a good correlation between the hydraulic simulation results and the field evaluation of the network.

Abstract Extended Abstract

The construction of underground dams is a method of controlling and storing water in wet periods for use in dry periods. Underground dams are structures for blocking water under the surface of the earth. Although the underground dam is considered a new method for water extraction, satisfactory results of their implementation have been reported in different parts of the world. This research was conducted with the aim of determining the appropriate site selection criteria for the construction of underground dams in Ben County, Chaharmahal and Bakhtiari province, Iran. The most important problem in the development and construction of underground dams is the complexity of determining suitable places for their establishment. Determining the most important criteria for identifying the suitable places, selecting the most suitable decision-making method in the integration of information layers, and ranking the vulnerable areas have greatly helped in the implementation of these structures.
The investigated area includes Ben township with an area of 14327 hectares, which is located in the north to northwest of Chaharmahal and Bakhtiari province. Ben, Vardanjan, and Yancheshmeh cities are located in this area. The research employed Boolean logic, aerial photos, and Landsat satellite images to identify 10 suitable axes for dam construction. Also the study utilized the Analytic Hierarchy Process (AHP) to prioritize the axes based on hydrological, economic-social parameteres. After specifying the axes in the first stage and determining their criteria and value, using the MADM method and based on the AHP decision-making method, the suitable points for the construction of the underground dam were prioritized. According to the studied area conditions and the available information, 4 main criteria, 3 sub-criteria and 17 indicators were used in the process of AHP. In the following, using the relative values determined by the binary comparison method for these indices and criteria, the appropriateness index was calculated for each axis.
In the hierarchical analysis method, inappropriate areas were eliminated in the first step using Boolean logic, and three elimination criteria: slope, land use and geology. Then with the field survey in the determined areas and using the Boolean method, 10 suitable axes were selected for the construction of the underground dam. To establish the priorities MADM method was employed based on the decision-making flow, also the AHP method was applied and questionnaire was analyzed using the Delphi method, to consider expert opinions. According to the value of the main criteria and indicators, hydrological factors are given priority with a weight of 0.51, followed by economic-social factors with a weight of 0.30, reservoir with a weight of 0.13, and axis with a weight of 0.058. The study identified the quantity of water (runoff height) and the depth of alluvium as the most critical indicators, with weights of 0.833 and 0.743, respectively. Subsequently, axis 1 (identified as B) and axis 2 (identified as A) were determined as the first and second priorities for consideration by the implementation department. The results showed that the quantity of water is more important than the quality. That is because in the absence or lack of subsurface flows, the reservoir of the underground dam is not completely drained, leading to many problems, including difficulties in suppling the water needs of the residents. According to the results, the higher the water quality (water hardness) has the greater relative importance. The downstream areas of pollution sources were considered as unsuitable places and removed. The results indicated that a larger reservoir volume will make it more suitable. The best places to construct an underground dam in a river are the gorges withthe highest reservoir level in the upstream areas. By the results of the reservoir depth factor, the best areas were the alluviums with a depth of less than 10 meters. The outcomes of the this investigation indicated that most of the waterways 3 and 4 were located on slopes of less than 5%, which were suitable areas for the construction of underground dams, because the slope factor has an inverse relationship with the volume of the reservoir and the amount of permeability. The depth and length of the dam axes are the most important economic factors in an underground dam, and due to the limitations in the axes drilling depth compared to the length of the axes, this criterion cocidered as the first priority. The suitable axes were those that, in addition to having a suitable reservoir for storing water upstream, had the minimum possible depth and length for the implementation of the wall. Shorter axes had more value and importance than other axes. Among the socio-economic sub-criteria, the factor affecting the water resources -especially the downstream qanats- was more important, because the change in the qanat water supply causes local challenges. The results revealed that the index of distance from the village was more important than the distance from the road. The existence of a road in the construction site of the underground dam increases the access and reduces the costs related to the construction and maintenance of the structure.

Abstract Extended Abstract

Nowadays, salinity stress is the most important abiotic stress for plants. Using saline water not only decreases yield but also reduces the amount of available fresh water and arable land that can be used for agriculture. By contrast, in soilless or hydroponic cultivation systems, plants are cultivated in an environment other than soil, in order to get to maximum plant density, improve yield and reduce soil contamination and nutrient uptake problems. Considering that tomato is a plant with high nutritional value and that it can be grown in different substrates, choosing a suitable substrate for cultivation with the ability to reduce the effects of salinity is important. In the current study, the effects of using activated carbon and potassium-enriched nanozeolite as an adsorbent were examined. The experiments were conducted under salty conditions (three levels) and the measured factors were: the yield, growth, physiological properties and water use efficiency of tomato.
This experiment was performed as a factorial experiment in a completely randomized design with three replications in the Faculty of Agriculture and Natural Resources of the Persian Gulf, 2022. The experiments were conducted in greenhouse conditions with temperature of 22 ± 5°^C and a relative humidity of 50 to 70%. Cultivation bed and irrigation water salinity were two factors considered in this study. Five types of culture media were prepared including basic culture media (cocopeat and perlite at 2/1v/v) and the treatments of activated carbon and nanozeolite enriched with potassium, at two levels (15 and 30g of each adsorbent were added to the one kilogram of basic culture medium). Saline water was used at three levels of 1.8, 3.5 and 5.5 dS/m of Hoagland solution. Salinity treatments were applied two weeks after the establishment of Adamino tomato seedlings in the culture bed, through the drip solution system, and continued until one week before the end of the experiment (120 days). The measured traits were total yield, average fruit weight, chlorophyll a, b and total, carotenoids, lycopene, vitamin C, TSS, TA of fruit extract, electrolyte leakage, relative content of leaf water, proline and water use efficiency.
The results showed that with increasing salinity to 5.5 dS/m, tomato yield, fruit weight, relative leaf water content, chlorophyll a, b, and total chlorophyll, carotenoid content, and water use efficiency significantly decreased (p< 0.01). However, the application of absorbent had a better effect on these traits by mitigating the impact of salinity. In contrast, increasing salinity elevated the levels of vitamin C, TSS, TA of fruit extract, electrolyte leakage, lycopene and proline of tomato shoots. Adverse effects of salinity on plant growth included osmotic stress, specific ion effects, and nutritional imbalance leading to morphological, physiological and biochemical disturbances. The result indicated that amending the substrate with activated carbon and potassium-enriched nanozeolite increased all studied traits of tomato except vitamin C, at all salinity levels (p< 0.01). The highest yield of tomato (6.66 kg), fruit weight (96.33 g) and water use efficiency (27.75 kg/m³) were related to the treatment of 15 g/kg potassium-enriched in culture medium with the solution of 1.8 dS/m. The application of 15 g/kg activated carbon and 30 g/kg potassium-enriched nanozeolite of culture medium increased the yield and fruit weight by 45% and 28%, respectively compared to the control treatment at the same salinity level. Zeolites consist of large open internal pores with a high cation-exchange capacity in crystal structure that result in high water holding capacity and nutrient retention. That improvement of the plant growth in zeolite-rich treatments may be associated with enhancement of macronutrient supplement and reduction of sodium uptake by plant root. Beside the effect of potassium in nanozeolite, the antagonistic relationship between potassium and sodium resulted in a reduction of sodium absorption by the plant. Therefore, it moderated the negative effects of salinity stress and increased indicators related to growth and yield and water use efficiency of tomato. It seems that the use of activated carbon in this research could reduce the effects of salinity stress due to its high specific surface area and porous structure. In general, the results of this study revealed the beneficial effects of activated carbon and enriched nanozeolite on properties of tomatoes (yield and phytochemical traits), and water use efficiency of tomato under salinity stress conditions.

Abstract Extended Abstract

Fars province is the most important dry fig producing province in Iran, accounting for over 90% of the country's fig production. More than 50% of the cultivated area of rainfed fig orchards in Fars province is located in Estahban region, which includes about 17% of the cultivated figs in the world. In recent decades, decrease in rainfall and drying up of the surrounding lakes have caused water stress in these orchards and loss of some trees. Supplementary irrigation reduces water stress, and pruning fig trees can also reduce the water consumption. In this research, the interaction of different levels of pruning and water stress on fig trees in the Estahban area was investigated.
In this study, three pruning treatments (light pruning, medium pruning, severe pruning) and four water stress treatments (water stress indices of 0.2, 0.4, 0.6 and no irrigation) were considered. This experiment was in the form of factorial with two factors (pruning and water stress index) in the form of randomized complete block design with three replications, at Estahban fig research station. Different levels of water stress index were obtained by measuring the temperature of tree canopy and the air temperature based on past researches. In the current research, the relationships provided by IDSO and previous researchers were used to apply different levels of the water stress index of fig trees. In this method, the difference between the temperature of tree canopy and the air temperature is related to the water stress of the plant. Therefore, based on the different levels of water stress, threshold temperature difference was determined, indicated when irrigation should be applied. Leaf temperature measurements started after the completion of leaf growth and were taken once a week. In order to determine the volume of irrigation water, the soil of the site was sampled and analyzed to measure the moisture content of the field capacity and the wilting point, and the bulk density of the soil. Hence, the volume of irrigation water determined 1500 liter per tree.
The results showed that in the first year, when the amount of rainfall was significantly higher, water stress occurred later in the trees. Water stress treatment with the index of 0.4 required irrigation only in the second year for light and medium pruning level. This treatment did not need a supplemental irrigation under severe pruning conditions. In all three years of the experiment, dry fig trees in the water stress index of 0.6 did not need supplementary irrigation at all three levels of pruning. It can be claimed that with pruning, the number of times of supplemental irrigation of rainfed fig trees was reduced. During the experiments, the amount of yield and water productivity increased, and this increase in yield was significant in the first and third years of the experiment. Also, the difference in water productivity in all three years of the experiment was significant. In different supplementary irrigation treatments, yield values and water productivity were not significantly different, but water productivity increased slightly by reduction in irrigation events. In different levels of pruning, yield values and water productivity did not differ significantly. Therefore, it can be said that pruning, even severe pruning, did not significantly reduce the yield and water productivity of rainfed fig trees. It is clear that the number of supplementary irrigations required by fig trees depends on the amount of water needed or evapotranspiration. That is, the more evapotranspiration, the more irrigation is needed. Moreover, the amount of evapotranspiration is related to the amount of evaporation from the pan in meteorological stations. Therefore, it can be said that the number of times of supplementary irrigation is related to the amount of evaporation from the evaporation pan of the weather station and its difference with the amount of rainfall. A simple linear relationship can be established between the number of times of supplementary irrigation and the difference between evaporation and rainfall. Having these relations, it is possible to predict the number of the supplementary irrigation events according to the difference in evaporation and rainfall. Of course, the mentioned relationships have been extracted according to the limited data obtained from this research. It is evident that increase in data volume leads to increase the accuracy of the extracted relationships.

Abstract Extended Abstract

Less than 1% of the Earth's water resources are suitable for human consumption, and clean water is essential for sustaining life and human activities. However, factors such as population growth, agriculture, industrialization, urbanization, and poor management have degraded water quality, rendering it unsuitable for consumption. Heavy metal pollution in aquatic environments is particularly concerning due to its direct impact on living organisms and indirect effects on human health. Toxic heavy metals, like cadmium (Cd), chromium (Cr), nickel (Ni), arsenic (As), lead (Pb), and iron (Fe), accumulate in fat and liver tissues of humans and animals, adversely affecting the nervous, blood circulatory, and immune systems. Some of these metals, such as Cd and Cr, are also carcinogenic. Therefore, accurate determination of the heavy metals concentration and monitoring water quality is crucial. The Karun-Dez river basin, located in southern Iran, is a critical water resource. The Dez River, a major tributary of the Karun River, supplies water to numerous cities and villages, thousands of acres of farmland, several fish farming projects, and industrial factories. The Karun River is vital for industries such as metal, petrochemical, and oil, which are situated along its banks. This river provides drinking water for cities like Ahvaz, Abadan, and Khorramshahr, and fish from the river are a primary source of protein for the local population, making heavy metal contamination a significant threat to food safety. As a result, monitoring heavy metal levels in the Karun and Dez rivers has become a focus for researchers. This study measured the concentrations of heavy metals in the Karun and Dez rivers, which supply water to treatment plants 1 to 5 in Ahvaz. Additionally, the outlet flows of these treatment plants and six distribution areas were examined. The metal levels were compared with World Health Organization standards, and water quality was assessed for heavy metal pollution using recognized global indices.
The study area encompasses the Karun and Dez rivers in Khuzestan Province. Given the vast extent of this region and the critical importance of river water quality for various uses, the section of the river serving as the water intake for the drinking water treatment plants of Ahvaz has been designated as the focus area. This study examined treatment plants No. 1, to 5 in Ahvaz, as well as six points from the city's distribution network. Sampling was conducted in two seasons: the wet season (winter 2022) and the dry season (summer 2023), from specified stations with three repetitions each. Samples were collected in acid-washed polyethylene containers, and the concentration of metals in each sample was determined using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES, model 730-ES, Varian). The results were plotted using GraphPad Prism software version 9 and compared with standard levels of metals in drinking water according to Iranian National Standards No. ISIRI1053, the World Health Organization (WHO, 2008) guidelines, the US Environmental Protection Agency, and Health Canada standards. The difference in heavy metal concentrations between the wet and dry seasons was analyzed using the T-test with SPSS software version 17. The Heavy Metal Pollution Index (HPI) and the Heavy Metal Evaluation Index (HEI), were determined for all inlet and outlet samples of the treatment plants and distribution points. The Metal Index (MI) was used to evaluate the potential impact of overall heavy metal pollution on public health and to aid in the rapid estimation of drinking water quality. Additionally, the degree of contamination (Cd), calculated as the sum of the contamination factors of individual components exceeding the permissible limit, was determined for all samples in both the wet and dry seasons.
The measurement results showed that the levels of metals Ag, As, Cd, Co, Hg, Pb, Sb, and Sn were zero in all inlet and outlet samples, and at six distribution points during both wet and dry seasons. Metals Ba, Cr, Cu, Mn, Mo, Ni, and Zn were detected below permissible standard limits in all samples from treatment plants and distribution points, with concentrations higher in the wet season than in the dry season (p<0.05). Concentrations of Cr, Cu, Mn, and Ni were significantly lower in the outlet samples from treatment plants compared to the inlet samples (p<0.05), indicated effective removal by the treatment plants. However, none of the treatment plants effectively removed Ba and Mo. The concentrations of Ti and V in all samples were below 0.19 ppm and 0.009 ppm, respectively. Their reduction in the outlet samples (p<0.05) suggested effective removal. During the wet season, Al levels exceeded permissible limits (p<0.05), primarily due to mineral waste released during thunderstorms and non-point sources. The presence of Al in outlet samples was linked to the use of polyaluminum chloride as a coagulant during treatment. Fe concentrations significantly decreased from inlet to outlet samples (p<0.05) and remained below permissible limits. The Heavy Metal Pollution Index (HPI) was below 100 in both winter and summer, indicated suitability for drinking regarding heavy metals. The Heavy Metal Evaluation Index (HEI) was below 10, also suggested the water's suitability for drinking. However in winter, the inlet water to treatment plants 3, 4, and 5, sourced from the Karun River, had an HEI value above 20 due to mineral waste, revealed unsuitability for drinking before treatment. Except for treatment plant 2 and distribution points 1, 2, 4, and 6, the Metal Index (MI) values generally exceeded 1that was in warning threshold. The high MI in the outlet samples from the treatment plants was due to the Al and Fe released from the coagulant materials used during the treatment process. Additionally, the elevated MI in the inlet streams during the wet season can be attributed to increased rainfall and the release of mineral wastes from thunderstorms and non-point sources. Inlet streams of treatment plants 3, 4, and 5 had Cd levels significantly higher than 3, classified them as highly polluted. A Cd index above 1 indicates metals exceeding permissible limits, with Al and Fe being the main contributors. Therefore, reducing the coagulant dose in the treatment process is recommended to lower MI and Cd indices.

Abstract Extended Abstract

Using unconventional water and reuse of wastewater is inevitable due to lack of available water resources. The scarcity of water resources particularly insufficient surface water can lead to several problems including instability in crop production, environmental negative impacts, and a decline in underground water levels that can result in the advance of sea water and mix with fresh water in coastal areas. In integrated water management approach, both surface and underground sources are utilized to meet water demands. Within this framework, treated wastewater plays a crucial role as a water resource, particularly in the countries which suffer from water scarcity such as Iran. Comparing surface water acquisition through building dams, withdrawal of underground water has several advantages, such as lower costs, reduced sedimentation and evaporation losses, less environmental quality concerns, and fewer significant environmental, social, and cultural impacts. The primary focuses of the current research included reuse of urban and agricultural wastewater for industrial purposes, construction, meeting demands of an eco-parks and cultivating non-fruit-bearing timber trees, among the sustainable approaches to manage the water resources and demands.
The current research was a survey through gathering necessary information and field visits. Various sources were reviewed, including articles, existed projects and plans, and theses. The interviews were conducted with experts and practitioners from related organizations included the Organization of Industry, Mining and Trade, the Industrial Settlements Company, Jihad Agriculture, The Regional Water Organization, and practitioners, experts and academic professionals. To identify and extract relevant indicators to the research topic, both national and international sources were reviewed for high-frequency factors. These factors were organized according to the conceptual framework of the research, which included three main dimensions of sustainable development: economic, social, and environmental. Also, nine sub-dimensions corresponding to these categories were defined. The stability, reliability, and accuracy of the indicators were evaluated and validated by Delphi technique and approved by the experts. The Delphi technique is used to identify and screen the most important decision indicators. Although this method is not a multi-criteria decision-making method, it is used in many cases to screen indicators or reach an agreement on the importance of decision indicators before applying multi-criteria decision-making techniques.‏ Regarding that the main goal of this research was to achieve sustainable management of Shahrekord's wastewater, scenarios were determined to the reuse of wastewater for non-productive trees, industrial demands, and eco-parks. To facilitate this purpose, fuzzy Shannon entropy and fuzzy multi-Morray techniques were employed. The sampling method of the statistical community in the present study was of a non-probable type. Snowball technique were applied to identify the targeted sampling and it was continued to reach the saturation point of 10 people of the experts of the field.
Investigations revealed that opinions regarding environmental quality variables varied significantly among experts, leading to different interpretations of what constitutes low or high quality. Given that experts possess unique characteristics and mentalities, their responses can differ based on these perspectives, which could undermine the analysis of variables. To standardize these responses, environmental quality variables were defined as triangular fuzzy numbers: Very Low: (0, 0, 0.25), Low: (0, 0.25, 0.5), Medium: (0.25, 0.5, 0.75), High: (0.5, 0.75, 1), Very High: (0.75, 1, 1). After identifying the relevant criteria, the relative weighting of the indicators were determined based on expert opinions. A questionnaire was developed for each project, utilizing a 5-point Likert scale, and distributed to 10 experts and observers in the field. Each expert evaluated the criteria based on the effective indicators identified in the previous phase. Shannon's fuzzy entropy technique was used to weight the indicators according to the scores.
After that the definitive and normalized weights for the 10 research indicators were established using the fuzzy Shannon entropy method, three options were ranked through the fuzzy ARAS method. Then the decision matrix and the ideal values were determined. Afterward, negative indicators were converted to positive values and normalized. Ultimately, the weighted matrix was formed and the score for each option were calculated. Consequently, the first priority for reuse of Shahrekors waste water is applying in industry; the second priority is to develop an eco-park in Shahrekord plain, regarding the benefits for environment and society as well as economic advantages; and the third priority is cultivation of non-fruit-bearing timber trees.

Abstract Abstract

Scouring may occur as a result of natural changes in the flow in the waterway or as a result of human activities such as construction of structures in the flow path or removal of bed materials.

The Occurrence of scouring around the abutment is considered as one of the most important 4- this phenomenon, several methods have been proposed. In the present study, the effect of two parameters of the geometric shape of the bridge abutment, as well as the presence of submerged vanes with selected arrangements, on the amount of scour around the bridge abutment was investigated. Most of the methods that are used to control and reduce scouring are divided into two categories: methods of changing the flow pattern and methods of increasing bed resistance, and researchers have used each of these methods to reduce scouring.

Methods:

In this research, a physical model of four different shapes including 90 degree rectangular, rectangular abutment with fin-wall with 60 degree flow line, rectangular abutment with fin- wall with 45 degree flow line and rectangular abutment with circular fins was designed and built. Submerged vanes were also tested in four different arrangements of parallel rows, zigzag rows, oblique zigzag and pine, in two Submergence ratios of 2 and 3 and at an angle of 20° to the flow on each of the four abutments, at constant discharge. The tests were performed at a flow rate of 34 liters per second and a water depth of 12 cm. The criterion of the equilibrium time in these experiments is the same criterion that Kumar et al. considered in their research, and it is equal to the time when the changes in scouring depth do not exceed one millimeter in three consecutive hours. Therefore, in the current research, by conducting a 12-hour test for each of the abutmentmodes, this duration was estimated to be 5 hours for all four types of abutment. All the experiments of this research were done in clear water conditions. At the beginning of the tests, four control tests were performed with the support in four different states and without the submerged vanes. After completing the tests, the maximum scouring depth for each abutment was obtained as follows: the maximum relative scouring depth of the rectangular abutments 90° 1.01, the maximum scouring depth of the rectangular abutment of the fin wall of the flow line 60° 0.43, The rectangular abutment of the fin wall of the 45 degree flow line was 0.41 and the rectangular abutment with circular fins was 0.36. In the following tests, for each of the different support states, the length and width of the scour hole were measured separately for four different arrangements of sunken plates, in two absorption ratios of 2 and 3.

Results:

According to the data of this series of tests, the absorption ratio (L/H=3) in all cases of submerged vanes and also for all abutments has a better performance than (L/H=2) in reducing surrounding erosion. Installation of plates in front of the abutment causes the approaching flow to break up and as a result reduce the strength of the downward flow and the horseshoe vortex in front of the abutment. If the ratio of the height on the submerged vane bed is high compared to its length, the vanes have enough height to separate the approaching flow. Observations showed that the maximum and minimum scouring depths occurred around the 90 degree rectangular and the rectangular abutment with circular walls, respectively. In submerged vanes experiments, the pine arrangement in a Submergence ratio of 3, with a 41% reduction in scouring around the 90 ° rectangular abutment, 20% around the rectangular abutment with fin- wall with 45 degree flow line and an 18% around the rectangular abutment with circular fins showed the best performance in reducing scour compared to the control test corresponding to each of the abutments. The comparisons made in this research show the effect of the shape of the abutment, in such a way that by changing the shape of the abutment from a 90 degree rectangle to a rectangle with circular fins, scouring was reduced by 64%. Also, with the presence of the protective device of the submerged vanes under the arrangement of pine in the absorption ratio of 3, the scouring decreased around the rectangular abutment 90 degrees is 41%, the rectangular fin wall of the flow line 45 degrees is 20% and the rectangle with circular fins is 18.18% compared to the control test.

Abstract Extended Abstract

In order to improve the management of water resources in basins, it is important to continuously assess the impact of inter-basin transfers. The water balance is an important tool for the management of these resources. Modeling the water balance of complex basins is a process that requires a thorough understanding of hydrologic behavior, geology, groundwater flow, a variety of data, and the effective use of modeling tools. In many watersheds where inter-basin water transfer occurs, especially if part of it is subsurface, there is insufficient information on how this transfer affects the water balance of the basin and its contribution to water resources.
In the current study hydrological modeling and field data analysis was used to assess the water balance in one of the major sub-basins of the Zayandehroud Basin, focusing on the impact of water transfer in this basin. As an innovation, this study utilized an integrated modeling approach. This approach combined the SWAT software, the results of the FEFLOW groundwater model for the adjacent area, and the development of a river water balance model in the Ghaleshahrokh basin. This integrated framework enabled the comprehensive evaluation of all flow components of the basin. Using SWAT software recalibrated with a Nash-Sutcliffe coefficient of 0.85, the atmospheric components of the water balance, including precipitation and evapotranspiration, were estimated and the resulting direct runoff and infiltration from the conversion of precipitation to runoff were derived. By using the results of the FEFLOW model in the aquifer of the study area adjacent to the research basin, it was also possible to estimate the return of water to the groundwater and the exchange with surface water. As a research innovation, a river water balance model was developed that achieves a Nash-Sutcliffe efficiency coefficient of 0.79 and a KGE coefficient of 0.75. Finally, in the water balance with a monthly time step, surface components such as the direct runoff, the base flow, the amounts of surface water transferred through the tunnel and the outflow from the spring, as groundwater transfer, were determined.
The results of this study which was conducted on Ghaleshahrokh basin, the main sub-basin of the Zayandehroud, revealed that regarding long-term average, the basin output is about 1127 and 1037 MCM/year, observed and calculated respectively. Also, 54% of the basin's output is attributed to the transfer of surface water through the first and second Kouhrang tunnels, 9% is due to the natural water outflow through springs ( such as Dimeh, as the major spring), 28% is direct runoff from precipitation and 9% consists of subsurface flows that forms the base flow of the river. The long term average rainfall of the basin is estimated about 1060 mm/year, with 28% of the total rainfall resulting in direct runoff, 22% in infiltration and the rest in evapotranspiration losses. The agricultural use in the basin was calculated to be 130 MCM/year. Considering that about 63% of the outflow from the study area, which supply the most of the volume of Zayandehroud dam, is discharged from outside the basin, both surface and subsurface, managers and policy makers should seriously consider expanding inter-basin cooperation. Since the contribution of water supplied by Kouhrang sub-basin is significant, adequate attention to this sub-basin is of particular importance both in terms of quantity and quality protection. It is also necessary to protect the discharging area of the Dime spring. Changes in rainfall, temperature, snow melting, as well as human activities such as land use change in the Kouhrang sub-basin and the discharging area of the Dime spring can greatly affect the quantity and quality of water entering the dam reservoir. Continuous review of water balance and analysis of inflow and outflow patterns, monitoring the quality of different water sources, planning for sustainable consumption development, managing flood risks or droughts, and generally developing long-term strategies and plans for sustainable use of water resources and environmental protection in the Ghaleshahrokh basin, as the origin basin of the inter-basin water transfer, are necessary. Also additional studies are suggested to understand the hydrological, monitoring and management of the process of inter-basin water transfer (naturally and artificially), and analyze their effects to ensure the sustainability of local habitats as well as supply the future water, and manage water resources regarding all environmental and social aspects.