Determination of the volume, peak discharge and peak time of flood hydrographs is a necessary task. This research uses of geomorphologic and geomorphoclimatic characteristic of watershed for estimation of flood hydrograph. Therefore it applies the Nash-IUH, Clark-IUH, Geomorphologic Instantaneous Unit Hydrograph (GIUH), Geomorphoclimatic Instantaneous Unit Hydrograph (GcIUH), GIUH- based Nash (GIUH-Nash) and GcIUH- based Clark (GcIUH- Clark) models. Because of using of geomorphologic parameters, GIUH and GcIUH models can be applied in watersheds that have historical storm (rainfall- runoff) events. The case study of this research is the Navrood watershed in the north of Iran. The derived flood hydrographs by GIUH and GcIUH models have triangular shapes and these models must be combined with the Nash and Clark models for modification of shape of flood hydrographs. For this purpose derived flood hydrographs by GIUH related to Nash-IUH parameters (shape and scale parameters) and derived flood hydrographs by GcIUH related to Clark-IUH parameters (time of concentration and storage coefficient parameters). The performance criteria are the Nash-Sutcliffe performance coefficient (NS) and root mean square error (RMSE) and the percentage error in volume (PEV), percentage error in peak (PEP) and percentage error in time to peak (PETP) are criteria for evaluation of accuracy of models. The results show that Clark-IUH and GcIUH-Clark are appropriate models for simulation of flood hydrographs while four other models can not state suitable simulated flood hydrographs. The sensitive analysis shows that the most sensitive parameters are infiltration constant rate (φ) and time concentration in Clark-IUH model. In objective function (RMSE), the values of sensitive analysis for these parameters are -0.27 and 0.03 respectively. Also the sensitive analysis shows that the most sensitive parameters are infiltration constant rate (φ) and storage coefficient in GcIUH-Clark model. In objective function (RMSE), the values of sensitive analysis for these parameters are -0.63 and 0.35 respectively. For evaluation of uncertainty of introduced data to models, this research utilized the Monte Carlo simulation method. This method produced 500 values for each data and rainfall –runoff models simulated the peak discharge of flood hydrographs for each produced data set. Uncertainty of data changes the value of simulated the peak discharge of flood hydrograph. For example, the observed peak discharge of flood hydrograph is 12.41 CMS in 15 May 2004. For 95% confidence interval, Uncertainty analysis shows that range of the peak discharge flood hydrograph is 4.05-22.36 and 3.73-21.76 for Clark-IUH and GcIUH-Clark models respectively.

One of abilities of weather radars is measurement of rainfall intensity with suitable time and space separation in different watersheds. For time and space separation, the observed radar reflectivity (Z) converts to rainfall intensity (R) by a transfer function also this transformation is performed indirectly. The form of this function is Z=aRb. In the first stage, for calibration of collected data by weather radar and determination of the best equation between the observed radar reflectivities (Z) and rainfall intensities (R), the stochastic methods were applied. The best performance criterion was RMSE. This criterion distinguished that equations Z=318R1.6 and Z=126R2 are optimum transfer functions. For the case study of this research (the Abolabbas watershed in east of the Khuzestan province) the equation Z=126R2 is more accurate than other equation. RMSE of this equation is 2.04 mm/hr while RMSE of the second equation (Z=318R1.6) is 2.11 mm/hr. In this stage precipitation time series with 15 minutes time steps were applied.
In second stage, HEC-HMS rainfall-runoff model was applied for simulation of flood hydrograph. For this purpose, four types of precipitation data were considered. Extracted rainfall data from radar and equations Z=126R2, Z=318R1.6 and Marshall-Palmer relation (Z=200R1.6) and extracted rainfall data from rainfall gauging stations. Results of HEC-HMS rainfall-runoff model showed that calibrated rainfall data by Marshall-Palmer relation are not suitable data for model. But calibrated rainfall data by Z=126R2 can produce flood hydrographs that their accuracy is similar to accuracy of generated flood hydrographs by collected rainfall data of rainfall gauging stations. Therefore this relation is a suitable transfer function between the observed radar reflectivities (Z) and rainfall intensities (R).

 

 One of the important issues in the management of reservoirs is the establishment of a relationship between short-term reservoir objectives such as flood control and long-term reservoir objectives, such as supplying of energy demands and agricultural and drinkable water demands simultaneously. By considering short-term or long-term objective alone, the desired operation of reservoirs will not be obtained.
For optimization of the operation of reservoir, a multi-objective optimization was applied in this research. The solution method for proposed optimization model is NSGA-II method. Dez Reservoir as the main storage component located on the Dez basin was considered as a case study. The objectives are maximize of generation of the hydroelectric energy meanwhile supplying of drinkable, industrial and agricultural water demands, and minimize of the peak flood discharge that outflow from the reservoir. The ultimate target of this multi-objective optimization is the interaction between the two objectives that the operator can choose an optimum solution among found optimum solutions.
To calculation of the amount of generated hydroelectric energy, a sub-model that simulated the operation of the reservoir using of SOP method was applied. The peak flood discharge with 10,000 years return period that outflow from the reservoir was obtained using of a flood management policy, this value was determined by considering the reservoir water level during flood. The results of the model are presented in several solutions that are not superior to each other (Pareto frontier). Selection of each of these solutions is dependent to the long-term programming for operation of reservoir and water resources management in the area of study. Optimum solution that increases percentage of depreciation of peak discharge of flood into reservoir dam decreases generation of hydroelectric energy and reservoir performance indicators

Interaction between tidal and fluvial flows is a complex problem of hydraulic and river engineering in tidal rivers. This research will find equations for prediction of HHW، LHW، HLW and LLW in Khorramshahr, Khosro-Abad and the Arvand Rood hydrometric stations using of GP method. These stations were constructed on the Karun River, the Bahmanshir River and the Arvand Rood respectively. This research considers trend, stationary and normality of tidal data too.
The Mann-Kendall test and skewness test were applied for trend and normality test respectively, also ADF and KPSS test were applied for stationary test.
The Mann-Kendall test did not show any trend in tidal data. Skewness test shows that normal probability distribution is not government on tidal data. Therefore logarithm, square root, first and second order differentiation, Box–Cox transformation functions were applied for reduction of skewness coefficient and making the data more normal distribution-like. The best function for this purpose is Box–Cox transformation function. This function reduce skewness coefficient more than other functions.
ADF test shows stationary of tidal data (in main tidal data and normalized tidal data by Box–Cox transformation function). Also KPSS test shows stationary of normalized tidal data by Box–Cox transformation function. For main tidal data, KPSS test shows stationary of tidal data in the Arvand Rood hydrometric station, stationary of HHW and LHW data in Khorramshahr hydrometric station.
The optimum values of different parameters of GP method were determined by error- trial method. These values are: Mutation rate= 0.03, Length of the head size= 10, Number of gene= 3, Number of used function= 4, Length of the tail= 11. Genetic programming states equations for prediction daily HHW، LHW، HLW and LLW. These equations are optimum combinations of HHW، LHW، HLW and LLW at one, two and three days ago.
 

 Climate change phenomenon can influence the amount of precipitation in all geographic regions. These influences can affect the Intensity-duration-frequency curves. The Intensity-duration-frequency curves are one of the most valuable tools for designing, programming, and operating in water resource projects. The purpose of this study is to obtain the relationships of Intensity-duration-frequency in Baghmaleq station in Khouzestan province in Zard-Roud region. Two methods for statistical distribution awere used to develop the IDF relationships from precipitation data in this specific area which are Gumbel and Log-pearson type 3. Initially, the precipitation data of Baghmaleq station which have been recorded in 40-year period (1974-2013) were gained from Institution of Water and Power in Khouzestan province and then the statistical calculation were granted and the distributions which have been best fitted with the data, were chosen and finally data with these distributions were fitted and with using mean square error technique, best distribution was chosen at the end. After that, an artificial neural network model was developed to downscale the data in upcoming time periods. At the end, data in a 30-year period (2020-2050) was fitted with the chosen distribution for HadCM3 general circulation model and A1B, B1 and A1 scenarios and also IDF curves were compared with basic period curves for all three mentioned scenarios.

 The drought is a natural and destructive phenomenon. In arid and semi-arid regions, prediction and evaluation of drought severity is necessary for water resources management. This research evaluates meteorological drought severity in the Khuzestan province. For this purpose it uses of Standardized Precipitation Index (SPI).
42 climatic stations were considered across this province. These stations have enough data and the length of the statistical period is 32 years for daily precipitation data. Using of daily precipitation data in climatic stations, SPI was calculated for 3, 6, 9 and 12 months time scales. For primary clustering of homogeneous regions, the MINITAB software was applied.
Using of homogeneity statistic, trial- error method and elimination of inappropriate stations, the Khuzestan province separated to 3 homogeneous regions for three months time scale and 2 homogeneous regions for 6, 9 and 12 months time scales. Linear momentum method was applied for Regional frequency analysis. Tool of this method is FREQ program in MATLAB. The best regional probability distribution was determined by ZDist stochastic and goodness-of-fit test. After selection of the best regional probability distribution, the values of SPI were calculated for each station, return period and time scale. These values can be used for evaluation of the drought severity in different stations.
The results of research show that severe droughts can occur in northwest, southwest and center of the Khuzestan province (Dezful, Shushtar and Shush cities). Also the severity of drought is less in east of the Khuzestan province (Izeh, Bagh-e malek, Ramhormoz cities). In Ahvaz and Masjed Soleyman, the probability of occurrence of severe droughts is less than other regions of the Khuzestan province.

Permanent deformation is one of the most important defects of asphalt pavements which is known as Rutting. This type of distress includes a compressed and squeezed surface along the wheel track that usually comes with swollen sides. Asphalt mixture ingredient’s characteristics and their mixture ratio, how to span the martial over the road surface, climate circumstances effect, average traffic speed on the road and pavement thickness could be named as main parameters which leads to rutting in case of wrong designing. Rutting is one of most common distresses on asphalt pavements all over the country especially in provinces which located in tropical zone and heavily loaded Such as Khuzestan province.
This thesis is an effort to pinpoint the causes of rutting phenomenon of asphalt pavements in Khuzestan province through field observations and laboratory tests. The approach to accomplish such task in this thesis is extracting samples from asphalt pavement of eleven significant roads located in the area and assessing those which were rutted in compare sent with those which were intact. This procedure led to choosing two types of gradation as the best gradation which causes less rutting. More over to determine the effects of bitumen type we assessed four kinds of the material (PG76-10, PG70-10, 40-50 and 60-70) which are widely used in the province produced by Pasargad Oil Company. Thus Considering two types of gradation, four types of bitumen and also adding three initiative mixtures and Iranian Standard asphalt mixture, the number rounds up to 15 different design mixture. Therefore 30 samples were carried out using Superpave Gyratory Compactor.
As the final part Results from Wheel-Track laboratory test were studied and the Optimized design mixture was selected. Future more applicable suggestions were made for reducing the rutting in asphalt surface pavement of Khuzestan province.

Determination of variations of cross sections is very important in rivers. Because of interaction between tidal and fluvial flows in tidal rivers, importance of this subject increases.
The case study of this research is the Karun River (between Ahvaz to Khorramshahr). Fluvial-12 model was applied for this purpose. Model calibration illustrated that Ackers – White (1973) empirical equation is the best equation. Results of this equation have the best fitness with variations of cross sections of river from 1996 to 2013. This equation improved results (average of difference between observations and results of different models) of other empirical equations (31% in Farsiat and 76% in Khorramshahr hydrometric stations). This model shows that tides with large return period produce great sedimentation near the mouth of the river while floods with large return period produce great sedimentation at other parts of river.
Also it is observed that floods with large return period cause great erosion and great deformations in river.
 

Constructing a dam in the river causes to disturbance of hydrodynamic balance, resulting in all or part of the sediments remain in the dam. The sedimentary deposits and distribution in the reservoir is the most important factor in estimating the useful life of the dam. Given the direct impact of the useful life of the dam on the efficiency of its economic, and since the life of reservoir is determined based on the amount of deposited in it, the problem of sedimentation in the reservoir is the most important economic factors in the project. The purpose of studying the sedimentation in reservoirs is to determine the amount and distribution of reservoir sedimentation or in other words, determining the temporal and spatial distribution of sediments in the reservoir. Due to the complexity of the process of deposition and since its mechanism is not well known, in this study the process of sedimentation in Karkheh dam is studied by GSTARS4 model during a period of 8 (2005-2013) and 40 (2005-2045) years. The results show that during the period of 8 years (2005-2013) about 56 million cubic meters of sediment has been entered in the Karkheh dam, which has reduced about 1.35 percent of the useful volume of the reservoir, and in the simulation of long-term (2005-2045), it is predicted that this percentage will increase to 6.28. Checking the changes in longitudinal profile states that the maximum sedimentation occurred in 20000 to 37000 meters of the dam.

 One of the biggest challenges in present century is climate change, which can be the source of many negative phenomena in the world and it can be one of the fundamental crisis of water sources managements. By attention to the importance of the mentioned issues, in this research we investigate about monthly changes of climatic and hydrological variables of discharge, rainfall and temperature in three hydrometric stations. These stations are located in upstream of the Dez dam (Tang 5 Bakhtiary, Telezang and Sepid Dasht Sezar). The applied methods in this research are nonparametric statistical Mann-Kendall testing, Sen and Pettitt estimator by 95% certainty in statistical period of 1977-2008. Pettitt testing shows that discharge and rainfall have meaningful change points. However change points in temperature are not meaningful. Also, the results of Mann-Kendall testing show that trend changes of discharge, rainfall and temperature in three stations at most months are decreasing. Then evaluation of different probability distributions by three methods such as moment, linear moments and maximum likelihood is discussed. By using Akaike information criterion, Bayes information criterion and rootmeansquare error for curve fitting, the governing distribution on each parameter is determined. After that, by using parametric linear regression and nonparametric Mann-Kendall method, the best model for prediction of discharge is selected. At the end, the probability distributions on forecasted data are fitted. Comparing governing distributions on observed and forecasted data shows that governing distributions on observed data can be used for forecasted data.

In recent years, morphological studies as a part of river fields hold a special position along with various goals, such that any practicing in river bed should consider the interaction with the river morphology. In this study, the dam construction effects on morphological situations of the Karkheh river have been discussed using the Fluvial-12 model. Comparing the flood discharge values before and after the dam construction indicated that the river floods extremely decrease for short return periods, So that the biennial river flood discharge with a normal value of 1739 cubic meters per second has reached to the 130 cubic meters per sec with a 14 time decline rate. Discharge falls into 7 time decrease for a 10-year return period. Dam construction also reduces the flood plain areas, especially for short return periods. The amount of sediment flow has also strongly decreased, particularly for floods with the return period less than 25 years. Although flood makes great alterations in river downstream, negligibly affects on the erosion. Based on the statistical reports from the Paipol, Abdolkhan and Hamidieh cross sections, we conclude that the river bed profile has been recently relatively stable and the channel slope will not significantly change in the future.

River floodplain and adjacent areas due to their specific circumstances enabling environment for economic and social activities are always exposed to the dangers of flooding. Therefore, in these areas to determine how far the floods and land surface elevation and height to determine the characteristics of different flood return periods that occur as flood zoning, will be of great importance.
The flood zoning, a prerequisite for proper development, construction criteria necessary to determine the ecological and environmental effects and identifies the investment risk. Connectivity some river hydraulic models with geographic information system (GIS) solutions to large gains and put in front of managers and planners.
Therefore, in this study geometric and hydrolic data of the Karkheh river in downstream of the dam (Distance Between Paypol and Hamidieh) were collected and then tests to check the suitability of the data (and, if necessary, restoration and reconstruction of data) to determine floods, maximum discharge values of floods and flood hydrograph for return periods of 2, 10, 25, 50 and 100 years.
To model the river in the state before and after construction of the dam Mike11 software was used. provided Hydraulic and geometric data, has introduced the model and calibration and verification of model done. Sections with geometric information had been completely filled and caused the error in yhe model by using a digital elevation model (DEM) and software Mike11GIS was widening and re-modeled to mike11. Then was flood zone and flood zoning maps for different return periods were prepared and comparisons for both state before and after construction of the dam was done . it was found that the area of flooding for floods with a return period of 25 years which is the basis for calculation of river bound about 60 percent decreased .To get better and match the zoning maps of the study area after superposition zoning maps with geo-referenced aerial photos, using software Flood Maps In Google Earth flood map imported to the sodftware Google Earth and areas around the river to flood risk was evaluated.
 

In Iran, one of the most important human factors that are induced changes in rivers can be referred to construction of dams. The aim of this study was to investigate morphology of Karkheh and knowing whether how these changes can be measured. For this purpose, Karkheh river in period of the years 2002 to 2014 from Pay-e-pool station up to Hamidieh station with the help of satellite imagery data and remote sensing to examine geometrical characteristics ( Meanders and Bends ) of river such as, sinuosity ratio, relative radius, central angle and Etc, which indicates that the river in the period of studies were more meander and the early period of the area been more unstable than the other part of the river. The results were also used to predict future changes.

Today, for water resources planning and locating sites for irrigation, industrial and municipal close to the river, determination of morphological characteristics of river is necessary. These characteristics are river width and slope and shape changes of river bed. The factors aggravate these changes and in Iran construction of dams is the most important of these factors.
Results of river classification method (Rosgen method) show that from 1383 to 1393 B-type between the Pay-e-pol to Abdolkhan increased significantly. This type of river is stable in plan and section. Type C reduced severe in all parts of the river and floodplain of this type of river is relatively unstable. This indicates that almost floodplain of river have found stability.
The E-type increased severe, this type of river has stable cross sections and plan. The model demonstrates the stability of the sides of the river. Type F has unstable plan and cross sections. This type decreased between Abdolkhan to Hamidieh while increased in the upstream part of rivers, especially near to Pay-e-pol.
 

 

Factors such as qualitative and quantitative limitations of water reservoirs and population growth reveal that due attention should be given to how to use water, how to confront with water shortage problems caused by water reservoir planning and how to offer methods to optimize them. Standard Operation Policy (SOP) is one of the reservoir operations within simulation models of water reservoir systems. This method has been known as the simplest method of water reservoir operation. Since, during drought, this method needs alterations, various methods such as hedging rule has been recommended. Two methods are used for hedging, Linear continuous hedging and Non-Linear continuous hedging. In order to determine the operation policy (demand management) during drought periods, it is indispensible to use a combination of optimization model with a comprehensive simulation model. To achieve this objective, one of the most efficient solutions is to apply Fireflymetaheuristic algorithm which is capable of connecting to simulation soft wares. optimizing operation from dam which is based on (agricultural needs ), direct relationship with the available supply and the input to reservoir. Standard operation policy which is one of the reservoir operation methods in simulation models of water reservoir systems is modeled within Matlabsoft ware by codifying. And its obtained results are compared with the results of two methods of hedging as methods of operation reservoir during droughts which have been codified in the form of optimization models together with simulation models. The comparison of the obtained results of Linear continuous hedging and Non-Linear continuous hedging methods with SOP method pointed out the priority of both hedging methods over SOP method in supplying low land water needs. Finally, comparing the results from Linear continuous hedging and Non-Linear continuous hedging revealed the priority of Linear continuous hedging over Non-Linear continuous hedging in supplying low land water needs.

کشور ایران به دلیل واقع شدن بخشهای عمده ای از آن در مناطق جغرافیایی خشک و نیمه خشک و ویژگیهای توپوگرافی آن از یک سو و توزیع ناموزون زمانی و مکانی بارندگیها از سوی دیگر در مرز تنش آبی قرار گرفته و لذا مدیریت جامع منابع آب و مهار این بحران جهت دستیابی به توسعه پایدار امری اجتناب ناپذیر می باشد. رشد روز افزون جمعیت و محدودیت منابع آبهای سطحی و زیر زمینی ، ضرورت مدیریت و بهینه سازی بهره برداری از منابع آب را ایجاب می کند .در این تحقیق یک مساله کلاسیک در حیطه مطالعات منابع آب و سد سازی یعنی تعیین ظرفیت بهینه مخزن سد لتیان با هدف تامین نیازهای آبی مورد مطالعه قرار گرفته است. حل مساله مذکور با استفاده از روشهای بهینه سازی و تکنیکهای شبیه سازی انجام شده است. از معروفترین روشهای بهینه سازی می توان برنامه ریزی خطی،غیرخطی وبرنامه ریزی پویا را نام برد. در این میان برنامه ریزی پویا به علت قابلیت حل مسایل خطی و غیر خطی و تطبیق آن با مسایل منابع آب از محبوبیت خاصی برخوردار است. در این تحقیق از روش برنامه ریزی پویا و مدل آبدهی (yield) جهت تعیین حجم بهینه مخزن سد لتیان استفاده شده است، برای تحقق این امر از نرم افزار لینگو بهره گرفته شده است. با توجه به حجم بهینه ،برای بدست آوردن تعداد ماههایی که در آن نیاز های آبی پایین دست برآورده نمی شود از تکنیک شبیه سازی استفاده شده است . با نتایج شبیه سازی یک رابطه رگرسیونی بر اساس حجم ورودی به مخزن وتعداد شکست (عدم تامین نیاز آبی پایین دست) استخراج می گردد . با تغییر دادن حجم ورودی،تعداد شکستها محاسبه می شود و با این نتایج یک شبکه عصبی مناسب آموزش داده می شود و برای سایر شرایط نتایج آن استخراج می گردد. براساس نتایج قبلی از شبکه عصبی رابطه رگرسیونی صحت سنجی می شود. در نهایت با استفاده از این رابطه و روش شبکه عصبی می توان تشخیص داد که در صورت بروز خشکسالی تا چه حد می توان آب مورد نیاز پایین دست را تامین نمود.