Sharif Digital Repository

Many communities in arid and semi-Arid areas rely on groundwater for drinking water. However, anthropogenic activities such as the use of fertilizers and human waste disposal impose the risk of nitrate pollution to the aquifers. With over 8.5 million population, Tehran, the capital of Iran, has experienced rapid population growth during the past decades while the majority of the city did not have a sewerage network and the main way of wastewater disposal was individual cesspits inside houses. The long-Term discharge of raw wastewater in cesspits has increased nitrate concentration in the Tehran aquifer which serves as a source of one-Third of drinking water for the city. Although the... 

One of the underlying factors in the conservation and development of urban green spaces is the available water resources use for green areas in each region. The primary purpose of this study is to introduce the integration of a proper simulation method for runoff along with AHP-PROMETHEE decision-making method for water resources management in urban basins. The application of this approach was investigated in the city Buin Zahra of Qazvin Province of Iran. In the first step by using the analytic hierarchy process (AHP), the available water resources in the case study were weighted. In the second step, the water resources of the municipal and residential wells and water collected by... 

In this paper the effect of the sulphate concentration on the performance of a three-stage anaerobic baffled packed-bed reactor (ABPR) was investigated. Synthetic wastewater (3000 mg COD/l) was used as the sole organic substrate. The 30 liters fixed-bed bioreactor filled with plastic packing and divided in three equal sections was used as the mABPR reactor. The unit was run at a hydraulic retention time (HRT) of 1 day and at temperature of 25° C. The results of this study showed that when COD/SO42- ratios were changed from 30 to 3 with increasing sulphate concentration from 100 to 1000 mg/l, COD removal slightly was decreased. Maximum COD and sulphate removal were 91 and 96%, respectively,... 

Thermal power generation needs great volumes of water for cooling purposes. A multi-period Low Water Generation Expansion Planning (LW-GEP) model is proposed to plan the future generation mix including type, capacity, time of installation, and proper cooling system of generation technologies to supply the future electric peak loads under the water resource limitations. Different types of generation technologies with conventional and modern cooling systems are considered as expansion candidates in the proposed LW-GEP model. The access of candidate and existing power plants to the water resources are considered. Renewable resources as water smart solutions are integrated in the proposed energy... 

The integration of water demand management measures using a multi-criteria decision making model is discussed. The demand management measures include leakage detection, water metering and distribution network rehabilitation. A Compromise Programming method is used for integration of criteria including economic efficiency, public health and sustainability. The model is found to be efficient for long-term plans for implementation and usage of resources and is capable of being employed by decision makers in comprehensive urban water management studies  

The present study has been conducted to investigate the effect of inlet flow regimes on vertical velocity and concentration profiles of the turbidity current. Experiments carried out on small scale channel and Kaolin with a density of 2.65 kg/m3 and a mean particle diameter of 4.5 μm, was used to generate the currents. Velocities were obtained at a rate of 10 Hz using an acoustic Doppler velocimeter. Using the siphon sampling approach, the acoustic backscattering intensity was calibrated and concentration was determined using a backscattering analysis. Results showed that the ratio of maximum velocity height to the height of the current was around 0.4-0.5 in sub- and super-critical regimes.... 

Flood as a natural disaster causes heavy human and economic losses and social unrests in most areas of the world. As flood control cost and flood damage compensation is a heavy burden over countries' budget, traditional flood design methods are being replaced by more reliable risk-based methods employing comprehensive risk analysis. In this respect, flood damage estimation is an important step in flood control systems design and analysis. In large river basins with complex reservoir systems and various land uses, flood damage estimation is complex, data-intensive, time demanding, and uncertain task requiring an intensive hydrologic and hydraulic analysis. In this study a simple approach is... 

Estimating precipitation at high spatial-temporal resolution is vital in manifold hydrological, meteorological and water management applications, especially over areas with un-gauged networks and regions where water resources are on the wane. This study aims to evaluate five downscaling methods to determine the accuracy and efficiency of which on generating high-resolution precipitation data at annual and monthly scales. To establish precipitation-Land surface characteristics relationship, environmental factors, including Normalized Difference Vegetation Index (NDVI), Land Surface Temperature (LST) and Digital Elevation Model (DEM), were considered as proxies in the spatial downscaling... 

Efficient environmental management calls for the consideration of multiple pollutants, for which two main types of transferable discharge permit (TDP) program have been described: separate permits that manage each pollutant individually in separate markets, with each permit based on the quantity of the pollutant or its environmental effects, and weighted-sum permits that aggregate several pollutants as a single commodity to be traded in a single market. In this paper, we perform a mathematical analysis of TDP programs for multiple pollutants that jointly affect the environment (i.e., interactive pollutants) and demonstrate the practicality of this approach for cost-efficient maintenance of... 

As concerning with water insecurity driven by water scarcity threatens the lives and livelihoods of humanity worldwide, urban water demand management is focused on promoting residential water conservation behaviors (WCBs) as a critical policy response to water scarcity. However, urban water conservation initiatives cannot be successful unless households involve in residential WCBs voluntarily by adopting water curtailment and/or water-efficiency actions. Thus, understanding motivations and mechanisms underlying accepting these two types of WCBs and interpreting their distinctions are primary policy considerations to make sustainable water consumption behaviors. Hence, the purpose of this...