IRAN-WATER RESOURCES RESEARCH
Year:2016 | Volume:12 | Issue:3|Papers Count:21

Bakhtegan Lake, as other lakes and wetlands, depends entirely on the state of water resources of the basin. The lake has been dried up since few years ago. It is believed that periods of drought events have caused this. Meanwhile, there is another hypothesis that the lake has dried up due to anthropogenic activities such as the increased water exploitation in the upstream as well as the effects of two large dams named Mollasadra and Sivand. The present paper aims to assess separately the effect of these factors on the changes in Bakhtegan Lake in the period of 1956 to 2014. The assessment was carried out using the Landsat satellite images and also by analyzing rainfall and discharge data collected by the Ministry of Energy throughout the lake basin including Kor River. To determine the amount of changes in the lake water volume the maximum likelihood classification method, in order to classify images, and post-processing comparison method, for verification of classified landuse of Bakhtegan Lake and its surrounding area, were adopted. The results showed that the reduced rainfall, and more importantly, the increase in the irrigated cultivated area in the upstream of the basin, which has resulted in increased water consumption, can be identified as the main causes of the lake drying up. The second factor has caused the problem of drought-induced water shortage to be transformed into a water crisis.

The challenges between Iran and Afghanistan have different aspects. Definitely, with water as the common point, the production of opium in Afghanistan and saving the environment of the eastern Iran are the most important ones. This research work aims to assess a new approach in the water-related interactions between Iran and Afghanistan using the sequential and issue linkage methods of game theory. A number of incentives like transfer of agricultural technologies are evaluated for possible decrease in opium cultivation simultaneously achieving more pay off for Afghanistan and increased inflows to Iran. The results showed that the successfulness of this strategic cooperation is highly dependent on opium price such that the incentives are efficient only for prices up to about $200 per kg of opium. For the higher prices their capacity reduces drastically. The research highlighted how issue linkage can be useful in international relations to solve a long lasting transboundary water conflict and achievement of a win-win solution for the riparian parties.

In order to supply reliable water to prioritized demands a comprehensive plan is needed. In this paper, the allocation of water resources in a basin is evaluated using two methods of administrative and market-based mechanisms. The study area is Balikhlichay river basin in Ardabil Province. First, in the administrative allocation, a nonlinear optimization model is developed to maximize the net benefit of farmers taking into account the system constraints. At this stage, the area of crops, the optimum amount of water and the shadow prices are obtained in each region. In the market-based allocation the optimization model is developed to maximize the economic value of irrigation water and defining tradable water rights. In order to reallocate the market benefits and establish a sustainable market, the concept of the cooperative game and Shapley value is then utilized. The benefits of the market are equitably distributed in a different coalition of consumers. The results of the administrative allocation model are considered as the initial water rights in the second model. The economic value of water is derived by calculating the area under the inverse water demand function curve for each region. The volume of water trades and the final allocated water are decision variables. The benefits of all consumers in the market will increase by cooperative game. Results indicated that water market in the Balikhlichay region can improve water use efficiency. The results showed that the market provides the potential for trading of about 18% of water rights among farmers in this region. Additionally, the results obtained in this paper showed that these trades would increase farmers’ profitability by about 9%.

One of the most efficient approaches for water demand management is to consider the economic aspects such as water markets. Once the social and legal frameworks of a water market is establiched, it is essential to provide an appropriate technical infrastructure for entering applicants into the market. Accordingly, this paper aims to implement technical infrastructure for organizing water market in five neighboring farms located in the Mahyar irrigation network in the Zayanderoud river basin. In this study, using an optimization model, a new cultivation pattern and monthly water exchange volume among farms have been determined. The objective function was to maximize the farmers’ profit and the constraints consisted of water, farm, and stock constraint. For evaluating different technical methods of groundwater transmission the associated costs of two transmission approaches, i.e. surface pumping and shared aquifer, were considered as input to the model. The model is implemented and executed at drought condition. In this condition, surface water is subtracted from the legal water rights of farmers. Results showed that by establishing water market, farmer returns were increased by 28 percent comparing to the base plan. Also exchanged volume of water in the market is 47 percent of the consumption water which shows the high cooperation of farmers in the market in order to achive a more optimal water allocation.

Nowadays, water quality simulation models help the experts to evaluate future potential scenarios according to extensive variety of conditions. The enhanced version of CE-QUAL-W2 (V3.72) as a 2D hydrodynamic and water quality model can help managers to find potential optimal solutions for downstream water temperature managements, determination of suitable aquatic habitat volume, and evaluation of environmental performance criteria according to various reservoir operation scenarios. Karkheh reservoir has been selected as the case for this research and providing suitable water temperature in March to May as downstream fish spawning months through the automatic selection of withdrawal port, surveying the habitat volume of biological valuable river fishes (Glyptothorax Silviae and Leuciscus cephalus), and evaluation of the environmental performance criteria (temperature and water quality parameters) have been studied according to various reservoir operation scenarios. Also the effects of probable pisciculture activity in Karkheh reservoir have been studied considering Phosphorus and Chla indices. The results showed that adjusting the automatic selection of withdraw ports in Karkheh reservoir could improve downstream water temperature for 0.86oC. Also the evaluation of environmental performance criteria indicated high priority of scenario 1 compared to other scenarios.

More accurate knowledge of the water balance components in the watersheds will help a better understanding of hydrological behavior of the watersheds. In this study, the effect of two components, river discharges and actual evapotranspiration, were investigated in modeling of the Neyshabour watershed (9500 km2) using SWAT (Soil Water Assessment Tool). SWAT was calibrated first with the river discharges values and then with the combination of river discharges and actual evapotranspiration obtained based on remote sensing. The model performance was validated in predicting these components for a separate time period. The sensitivity analysis results showed that parameters such as available water content, soil evaporation compensation coefficient, and plant uptake compensation factor were most sensitive to changes of input model parameters. The results showed as well that in three hydrometric stations of Andarab, Kharve Majmoo, and Hossein Abad the root mean square error for river discharges predictions on the validation period varied between 0.06 to 0.19 m3/s and 0.02 to 0.09 m3/s respectively for the models calibrated based on river discharges and combination of river discharges and actual evapotranspiration. The use of both mentioned components, i.e. river discharge and actual evapotranspiration, was prominently affected the predicting actual evapotranspiration. The root mean square error for actual evapotranspiration prediction in three selected subbasins varied between 10 to 18.52 mm/month and 6.84 to 7.82 mm/month for the models calibrated based on river discharges and combination of river discharges and actual evapotranspiration, respectively. Therefore, simultaneous use of river discharge and actual evapotranspiration improved the accuracy of modeling.

In the present study, DREAM(ZS) (DiffeRential Evolution Adaptive Metropolis) is used to investigate uncertainty of parameters in the HEC-HMS flood modeling in Tamar watershed (1530 km2) in Golestan province. In order to assess the uncertainty of 24 parameters used in HMS three flood events were used to calibrate and one flood event was used to validate the posterior distributions. Moreover, performance of five different likelihood functions (L1-L5) was assessed by means of DREAM(ZS) approach. Three likelihood functions, L1, L2 and L3, are considered as informal whereas remaining (L4 and L5) is represented as formal categories. Likelihood function L1 is Nash–Sutcliffe (NS) efficiency and L2 is based on minimum mean square error. L3 uses estimation of model error variance and L4 focuses on the relationship between the traditional least squares fitting and the Bayesian inference. In likelihood function L5 the serial dependence of residual errors is accounted using a first-order autoregressive (AR) model of the residuals. According to the results sensitivities of the parameters depend strongly on the likelihood function and vary for different likelihood functions. Most of the parameters were better defined by likelihood functions L4 and L5 and showed high sensitivities to model performance. Calculating P-factor values (percentage of measured data bracketed by 95% prediction uncertainty) showed that 75-100% of observed data were ranged in 95% total prediction uncertainty. Considering all the statistical indicators and criteria of uncertainty assessment, including P-factor and R-factor (relative width of the 95% prediction uncertainty), root-mean-square error (RMSE), Kling-Gupta Efficiency (KGE), and Nash-Sutcliffe (NS) the results showed that DREAM(ZS) algorithm performed better under formal likelihood functions L4 and L5.

Agriculture, as the main water consumer in Qazvin plain, has attracted the most attention in water resources planning. In this study, water accounting and virtual water trade concepts is used to determine t optimal crop pattern in Qazvin plain for better agricultural water management. The results showed that total water footprints and water resources footprints are about 2053 and 1411 MCM/year for period of 2003-2014, respectively. About 49.8 percent of virtual water footprint, 55.5 percent of water resources footprint, and 55.0 percent of net benefit were due to agricultural product export. Ceasing export of main crops from the plain would increase the average economical water footprint from 707.2 to 780.3 m3/ million Rials. This would not increase the net benefit per unit of water, but would even decrease it. Twelve scenarios were defined to determine crop patterns while sustaining the current cultivation area, net benefit, and water resources saving. Closest scenarios to the current crop pattern and cultivated area, i.e. scenarios 9 and 11, saved 23.3 and 23.8 percent of the region’s water resources, respectively. These two scenarios respectively improved economical water footprint up to 521.3 and 503.7 m3 per one million Rials.

Identifying organizational stakeholders in water resources management is one of the requirements for making plans operational and applying participatory management on water resources. Based on the network analysis method with a comprehensive perspective, we could study the structural patterns resulted from mutual relations of different stakeholders in a multi-faced and complicated system and investigate their roles in establishing an integrated and participatory system for water resources management. This study aims to identify the power structure and its distribution as a function of relations and setup of the involved organizations in water resources management in Garmsar plain by applying network analysis pattern. In this regard, at first, 29 organizations related to water resources management were identified based on ecological network boundaries. The information exchange and cooperation among them were then investigated by half-structured interviews. Finally, the power, influence, and control of each stakeholder were determined based on degree centrality, beta centrality, and eigenvector centrality. The results of this study demonstrated the inequality of power structures among organizational stakeholders in establishing a participatory management system in the considered region.

Due to the limited resources of water it is vital to investigate the quantity condition of reservoirs in order to plan for different usage of water as well as monitoring the sedimentation process. In this study the OLI sensor data from LANDSAT-8 satellite for Jan 2015 is used for producing Chah Nimeh water reservoir depth map and the map for the area around the lake. The water depths were measured with meter using boat. Water indices such as MNDWI, NDWI, AWEL, WRI and NDMI were generated using satellite data. By running simple linear regression between each index and field data the description coefficient R2 for water depth was calculated. Finally the water depth map was produced using MNDWI index which had the highest R2 equal to 0.85. The water depth map was produced using reclassifying of the MNDWI index. The map for the reservoir adjacent lands was generated using depth measuring results and hybrid image classification method. Results showed that the highest area are associated to 4-6m level depth. Map accuracy was assessed by producing error matrix which showed acceptable accuracy. Results showed that the map accuracy decreased with increase in water depth. The Z-TEST analysis showed however that in 0.01 level there was no significant difference between lowest depth map and deep water map accuracy.

Salinity control and water logging prevention are among the most important purposes of draining in agricultural lands. Accordingly, drainage is considered as an inseparable part of the irrigated agriculture in many areas of Iran. The major problem of drainage is the discharge of drain water into the environment. Devastating environmental impacts are consequently seen due to soil salinity in many parts of the country, especially in Khuzestan province. Since the reduction of environmental impact leads to increase in construction costs, the aim of this study is to present a model to define the design parameters, including diameter, depth, and distance, that not only meets the economic objective (construction costs) but also addresses the environmental issues (increase the quality of discharged drain water). Due to different nature of economic and environmental objectives, multi objective model should be employed. Evolutionary optimization methods are powerful tools to solve multi objective optimization problem. For this purpose NSGA II, based on GA and specified for multi objective problem, was employed in this study. To apply the proposed model Selman Farsi agro-industry was chosen as a case study. Results showed that better quality of discharged drain water could be achieved by increasing construction costs and reduction of installation depth. A %100 increase in construction costs due to change in installation depth could result in a %50 improvement in discharged drain water salinity. Also results showed that both economic and environmental goals, along with sustainable development, will be achieved simultaneously for the pipes placed in depthes between 1.3 and 1.8, distanced between 30 and 80 meters, and 0.1 in diameter.

Considering the climatic condition, drought is an inevitable phenomenon in Iran. The probability of the drought occurrence can however be predicted using the recorded meteorological data. Due to the drought importance and its impact on groundwater resources, the influence of drought on groundwater quality and ground water table of Qorveh-Chardoli plain was evaluated in this study during the last 25 years period. Monthly precipitation data (1987-2013) were applied to calculate the standardized Precipitation Index (SPI) which was then used to find the dry and wet years. Groundwater quality was also determined using electrical conductivity and sodium adsorption ratio and considering the Wilcox diagram. Kriging map of the water quality and water table were produced for wet and dry years. Groundwater quality of the Qurveh-Chardoli aquifer were classified as C2S1 and C3S1. There was no significant change in the water quality even during the wet period with raising water table. Groundwater level has changed 29.35 meters (increasing) and 13.39 meters (decreasing) during the dry and wet periods, respectively. The overall rate of decrease in the water level during the study period was 49 centimeter per year. The greatest decrease in water level were observed for eastern and southern parts of the plain.

In recent decades the increasing population pressures, improved living standards, and increasing demand for environmental quality have urged governments to provide better solutions for efficient water resources management. Since agriculture is the largest consumer of water, providing proper water resource management practices and codification correct policies in this sector is vital. In the present study the economic analysis of the effects of irrigation quota on cropping patterns and gross profit of farmers in Amol County is performed using positive mathematical programming model. The model was developed using data of cropping season of 2013-14 for irrigated lands of the county (Dashtesar, Marandeh, Raeisabad and Oskumahaleh). To achieve the study goals firstly the production function with constant elasticity of substitution and then the Quadratic cost function were included in the Positive Mathematical Programming models. The results illustrated that water rationing policy will lead to reduced acreage of most of the irrigated agricultural products in Amol county. Canola in the Dashtesar, Marandeh, and Raeisabad and clover crop in the Oskumahaleh area have undergone the most decrease compared to other crops. Also the applied water rationing resulted in increase in acreage of products with high profit and low water requirements such as rice and maize crops in all regions with irrigated agriculture.

Turbidity currents are one of the factors affecting sedimentation in reservoirs which reduces the water capacity of reservoirs and useful life of dams. Opening bottom gates is a conventional method for venting these currents preserving the useful volume of the reservoir. Choose suitable heights for gates on a dam has variety of functions in management of reservoirs and as well can have a major impact on the outflow water quality. This study have tried to investigate the effect of selective withdrawal on venting of turbid density current through reservoir’s outlet. For this purpose four gates have been established on a wall at the end of a flume at heights of 5, 15, 25 and 40 percent of ambient fluid depth. The Turbidity current input with concentrations of 5, 15 and 30 g/L were injected with a constant volume flow rate. The results showed that when the gate was placed at 5 percent of the fluid depth, the amount of output concentration was averagely 10 percent higher than the concentration of input turbidity current. Keeping the gates open for longer durations has increased the venting efficiency to 40 percent in different depths.

Development of hydraulic geometry relationships are of great importance in different applications of stream restoration design and hydrological modeling. Accordingly the main objective of this study was to develop regional relationships for bankfull channel dimensions in Tarwal basin using the drainage area as an independent variable. Several fieldworks, focused on Chameh Sis, Sangeh Siah, and Ozon Dareh tributaries as well as the main channel of Tarwal River, were conducted between 4 and 19 November 2015. Twenty two stable-channel cross sections were used to obtain the relationship among the bankfull channel dimensions and the drainage area. The results indicated that piecewise models are the best models for such relations. Simple power regression models were assessed as not suitable models for predicting hydraulic geometry according to the Relative Root Mean Squared Error (RRMSE) values of greater than 0.4. While for the piecewise models the RRMSE values were less than 0.2 for predicting bankfull cross sectional area and width of stable alluvial channels in basins smaller than 1165 km2. Also the RRMSE values were less than 0.12 and 0.25 respectively for predicting mean and maximum bankfull depth of stable alluvial channels in basins smaller than 100 km2. Nevertheless there were no ideal model to estimate bankfull channel dimensions in basins larger than 1165 Km2. This could be a result of significant changes in rainfall-runoff relationships or the influences of anthropogenic disturbances in large basins. The results provided useful data for stream restoration as well as water structure design.

Regarding the decrease in water resources especially in Iran, the river flow forecasting has gained a high importance and it is necessary to use the best methods for such forecasts. In this study the performance of some linear and nonlinear models was investigated for predicting the monthly flow of Jamishan River in Kermanshah province. The models include autoregressive integrated moving average (ARIMA), artificial neural networks (ANN) and adaptive neuro-fuzzy inference system (ANFIS). In using ARIMA model considering five parameters of any kind, all possible models were evaluated. For ANFIS and ANN models with determination of 14 different input combinations, the best models were identified. The capability of obtained models in long-term flow prediction was also assessed. The results revealed that ANFIS model is more capable in identifying the effective time delays in flow compared to ANN. This model is also more accurate than other models in peak values prediction. ARIMA model on the other hand has high capability in prediction of low values. Study indicated that all three models can be used for long-term predictions.

Certainty about the water quality for drinking, agricultural, industrial or recreational purposes is of prime importance. Accordingly assessment of river water quality can be an important element in the evaluation of water resources. The present study investigated the water quality of Aras River to provide an overview of the relationship and sources of physicochemical variables. A total of 20 samples were taken from the Aras River at 10 stations of which 10 samples were used for the analysis of heavy metals and 10 samples for nitrate, nitrite, Na, Ca, K, pH, EC and TDS variables. Atomic Absorption Spectro-photometry, Spectrophotometer, Flame Photometer, and pH and EC Meters were used for measuring water quality variables. The results showed that the mean concentration of nitrate, nitrite, sodium, potassium, calcium, and TDS in the Aras River were 297, 0.57, 67.3, 6.4, 57.4, and 1014.73 mg/l, respectively. Lead and cadmium contents were measured as 0.07 and 0.61 mg/l, respectively. Also the mean value of electrical conductivity was 1254.3 μs/cm and the mean value of pH was 8.22. The concentration of nitrate, nitrite and electrical conductivity were higher than the acceptable WHO standard and other variables were less than or within the WHO standard range. It seems that municipal wastewater and agricultural runoff are important factors affecting the water quality in Aras River.

In this study the analytical and numerical methods are presented for computing the unconfined steady state seepage velocity from a curved canal with semicircle cross section with T/Y=2. The analytical solution of seepage from curved canals has not been generalized due to the difficulty of conformal mapping of their cross sections. In the present study the velocity hodograph and the Schwarz-Christoffel transformation have been used for this purpose. Then the computation of analytical solution of seepage velocity was performed in which the drainage layer has lied in infinite depth. Along with this analytical solution a numerical modeling has been used based on finite element method using commercial software SEEP/W. Because of availability of high-speed digital computers along with specialized softwares, the approximate solutions by numerical methods have gained importance. The verification of numerical modeling was performed using the results of available analytical solutions of seepage discharge from a trapezoidal canal cross section. The results show that the numerical method has an acceptable accuracy in comparison with the analytical solution and can be used to estimate seepage velocity through the semicircle canals.