Showing papers in "Journal of Waste Water Treatment and Analysis in 2015"

Application of the HEC-HMS Model for Runoff Simulation of Upper Blue Nile River Basin

Abstract: Hydrological models have been used in different River basins across the world for better understanding of the hydrological processes and the water resources availability. It is important to use hydrological model today to assess and predict the water availability of river basins due to climate change to develop a strategies in order to cope up with the changing environment. It is very crucial to properly calibrate and validate models to give confidence to model users in prediction of stream flow. In this study HEC-HMS 3.5 hydrologic model (Developed by US Hydrologic Engineering Center-SMA (with Soil moisture Accounting Algorithm) has been used to calibrate (from 1988-2000) and validate (from 2001-2005) the upper Blue Nile River Basin (Gilgel Abay, Gumera, Ribb and Megech catchment). The model performance tested for each catchment in simulation the runoff flow during calibration and validation period, The Nash-Sutcliff (ENS) and Coefficient of determination (R2) used to evaluate the performance of the model. The results obtained are satisfactory and accepted for simulation of runoff. The deficit and constant loss method, synder unit hydrograph method and exponential recession method, are the best fit performed methods of the hydrological processes of infiltration loss, direct runoff transformation and base flow part respectively. Thus, this study shows that HEC-HMS hydrological model can be used to model the upper Blue Nile River basin catchments for better assessment and prediction of simulation of the hydrological responses. The study recommends further studies which incorporate the land use change of the basin in the model.

Acid Mine Drainage in Chile: An Opportunity to Apply Bioremediation Technology

Abstract: The use of micro organisms for heavy metal remediation in water is a technique widely studied. This review describes a number of methods used for Acid Mine Drainage (AMD) remediation, containing high concentration of this type of contaminant. The AMD is a problem generated in abandoned mines and low grade stock of active mines, therefore it is an existing problem in mining countries. In this review it is described the problem in Chile, regulations and the challenge to resolved this problem for a sustainable industrial future.

Dam site selection using remote sensing techniques and geographical information system to control flood events in Tabuk city.

Abstract: Constructing dams around the city of Tabuk is an important solution to controlling flood events, as well as increasing surface water budget and creating ground water recharge spots. The success of this effort is mainly based on locating the best site for a dam in the area. The aim of this study is to demonstrate the use of remote sensing, and geographic information system in dam site selection within the context of a catchment scale. Digital Elevation Model was used from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER 30m) to characterise the catchment area. Enhanced Thematic Mapper Plus images (ETM+) from LandSat 7 were used to classify the land cover in the study area. Several software packages such as ERDAS 11, Global Mapper 15.2 and ArcGIS 10.1 were used to construct and process the basic database. In addition, model builder from ArcGIS 10.1 was employed to construct a simplified model and integratesraster and vector datasets. The parameters of this model were: catchment slope (less 3%), delineation network order more than or equal to 7 and Runoff Coefficient (0.4). Six suitable locations were chosen: Wadi Dam in connection with Wadi Al Baqqr, Wadi Na’am, Wadi Atanah, Wadi Abu Nishayfah A, Wadi Abu Nishayfah B and Qa’a Sharawra.

Assessing the Impacts of Land Use-Cover Change on Hydrology of Melka Kuntrie Subbasin in Ethiopia, Using a Conceptual Hydrological Model

Abstract: The growth of population and its effect on the land use-cover change have been influencing the hydrology of the sub basin by changing the magnitude of stream flow and groundwater flow. In this paper, the likely land use-cover change impacts on hydrology of the Melka Kuntrie sub basin in the Upper Awash River Basin have been evaluated using the semi-distributed HBV hydrological model and Landsat imageries for two different periods. ArcGIS was used to generate the land use-cover maps from Landsat 5 TM and 7 ETM+ acquired, in the year 1986 and 2003, respectively. The land use-cover maps were generated using the Maximum Likelihood Algorithm of Supervised Classification. The accuracy of the classified maps was assessed using contingency matrix. The result of this analysis showed that the cultivated land has expanded from 1986 to 2003. The land use in 2003, which was mostly converted to agriculture land from forest, grass, or shrub land, showed an increased stream flow in the main rainy season, while the stream flow in dry or small rainy season indicted inconsistency from month to month. In the same time, there was a decrease in evapotranspiration in 2003 land use. The stream flow increased by the 2003 land use was 25% in June, 4% in July, 6% in August and 9% in September that corresponded to 0.065 mm/day in June, 0.077 mm/day in July, 0.07 mm/day in August and 0.039 mm/day in September for the main rainy season as compared to the 1986 land use. The model calibration was carried out using observed hydrometeorological data from 1991 to 2004 and the validation period was from 2005 to 2008. The performance of the HBV model for both calibration and validation was reasonable well and the Nash-Sutcliffe efficiency was 0.86 and 0.78 for calibration and validation, respectively.

Groundwater Exploration for Water Well Site Locations Using Geophysical Survey Methods

Abstract: Groundwater exploration is the investigation of underground formations to understand the hydrologic cycle, know the groundwater quality, and identify the nature, number and type of aquifers. There are different groundwater exploration methods. Surface geophysical method is one of the groundwater investigation methods. One of the surface geophysical methods is therefore the vertical electrical sounding method. Vertical Electrical Sounding (VES) is one to provide valuable information regarding the vertical successions of subsurface geo-materials in terms of their individual thicknesses and corresponding resistivity values. It is rapid and much effective in estimating aquifer thickness of an area and is cost effective technique for groundwater study. The objective of this study was therefore to locate two well site locations using surface geophysical methods for water supply purposes. However, hydrogeological and geological investigations were also incorporated in addition to the geophysical surveying activities for the betterment of the project. Finally, the intended well site locations with their corresponding thickness and resistivity values were identified using the integrated approaches.

Assessment of Groundwater Quality for Drinking Purpose by Using Water Quality Index (WQI) in Muzaffarnagar and Shamli Districts, Uttar Pradesh, India

Abstract: A water quality index (WQI) numerically summarizes the information from multiple water quality parameters into a single value that is understandable and usable by the public. This information can be used to assess spatial and temporal variations in overall water quality. However, these indices are time and region specific and may be influenced by local factors. Muzaffarnagar and Shamli districts of Uttar Pradesh are situated in Ganga-Yamuna doab of fertile alluvium of Indo-gangetic basin where the demands for surface water and groundwater are growing with rapid increase in agricultural and industrial activities. In the present study, water quality index is worked out to assess the spatial variation of groundwater quality status for future planning and management of Muzaffarnagar and Shamli districts using WQI. Data of 104 groundwater samples covering the whole districts have been used. The Water Quality Index has been computed using five parameters viz., pH, Total Dissolved Solids, Total Hardness, Chloride and Sulphate. The WQI results show that the overall water quality class is ‘good’ and water is acceptable for domestic use.

Performance Evaluation of SWAT Model for Land Use and Land Cover Changes in Semi-Arid Climatic Conditions: A Review

Abstract: Evaluation of land use land cover changes on the hydrological regime of river basins is one of the concerns in the global climate change. With plethora of tools available in the literature choosing of an appropriate tool that can quantify and analyze the impact of land use land cover changes on the hydrological regime in a systematic and planned manner is important. Soil and Water Assessment Tool (SWAT) integrated with Geographic Information System (GIS) based interfaces and its easy linkage to sensitivity, calibration and uncertainty analysis tools made its applicability more simple and has great potential in simulation of the past, present and future scenarios. A number of standards were used to appraise the model set-up, model performances, physical representation of the model parameters, and the accuracy of the hydrological model balance to assess the models that are defined in journal papers. On the basis of performance indicators, the mainstream of the SWAT models were categorized as providing satisfactory to very good. This review debates on the application of SWAT in analyzing land use land cover changes in semi-arid environment. Application of SWAT and land use land cover simulation models for impact assessment in semi-arid region improves accuracy, reduces costs, and allows the simulation of a wide variety of conservation practices at watershed scale. It is also observed that different researchers and/or model versions bring about in different outcomes while a comparison of SWAT model applications on similar case study was applied. This review determines the interactive role of SWAT and GIS technologies in improving integrated watershed management in semi-arid environments.

Assessment of Hydrological Impacts of Mau Forest, Kenya

Abstract: Mau Forest Complex is the largest closed-canopy montane ecosystem in Eastern Africa that encompasses seven forest blocks namely Mau Narok, Maasai Mau, Eastern Mau, Western Mau, Southern Mau, South West Mau and Transmara regions and the main catchment area for 12 rivers. However, over the past years, it has undergone significant land use changes due to increased human population demanding land for settlement and subsistence agriculture. Previous studies carried out in Mau have always demonstrated the relationship between deforestation and rate of forest degradation, but the effects on water quality and the impact on tourism resulting from the flamingoes migration has not been addressed adequately. Using Landsat images for four different epochs that is 1984, 1994, 2003 and 2015 comparative analysis of landuse land-cover (LULC) changes was carried out. The study demonstrated that the size of forest cover in Mau have been changing from 1984 to present. This is due to deforestation and agricultural activities taking place within the forested areas of Mau.

Tide and Mixing Characteristics in Sundarbans Estuarine River System

Abstract: Sundarbans Estuarine System (SES, 21.25°-22.5° N and 88.25°-89.5° E), comprising the southernmost part of the Indian portion of the Ganga-Bramhaputra delta bordering the Bay of Bengal, is India’s largest monsoonal, macrotidal delta front system. Sundarbans Estuarine Programme (SEP), the first comprehensive observational programme to study tidal as well as salinity features was conducted during 18-21 March, 2011 (Equinoctial spring phase). The main objective of this program was to monitor tides and salinity characteristics within the SES. Out of 30 observation stations, spread over more than 3,600 sq km covering seven inner estuaries, we have chosen river Jagaddal, which is connected with Saptamukhi East Gulley (SEG) in the West and river Thakuran in the East, due to the fact that the station Indrapur situated on this river at location very close to Bay of Bengal represents the condition at the mouth of all seven estuaries. Tidal elevation, salinity, bathymetry and vertical profile of salinity using CTD were measured during the observation period. Observed current data collected from different sources have been used for comparison with computed tidal current. Finally, the estuarine current, bottom drag coefficient and gradient Richardson number have also been computed. Computed values of these parameters have analyzed for interpreting variations for tidal, current and mixing feature prevailing in the estuary.

Snyder Unit Hydrograph and GIS for Estimation of Flood for Un-Gauged Catchments in Lower Tapi Basin,India

Abstract: In the flood prone catchments, it is needful to estimate the discharge, standard lag time, time of peak, and flood response of each watershed in the basin. The SUH method offers considerable advantage over others, and thus, has been chosen for estimation of flood response, contribution of flooding potential, percentage of flood volume for 25 sub-watersheds. The discretion of sub-watershed for estimation of peak discharge, time of peak, alternate lag time, and width of SUH at 50% and 75% of peak found to offer advantages over other methods. This paper considers Snyder Unit Hydrograph (SUH) with GIS based spatial database for calculating discharge at Lower Tapi Basin (LTB). The hydrological parameters of each sub-watershed such as river length, length of centroid, spatial area, land use, lateral slope, and terrain and soil factors have been extracted from GIS database. The geo-data has been combined with topographical maps to produce a digital elevation model (DEM) of 50 m cell size. The analysis for all 25 subwatersheds exhibit that 35.07 m3/s and 4.55 m3/s and 13.23 hours and 4.33 hours have been highest and lowest peak flow and time of peak respectively. The SUH model has been validated for peak discharge at a gauge site Amli (E73023' N21023') where discharge data were collected during 2010 and 2011 monsoon. A comparison between measured and SUH modelled discharge shows good fit within a mean variability range of 5-7%. The SUH methods ability to estimate hydrological parameters including peak flow discharge shows wider replication for un-gauged catchments.

Groundwater Modeling of Multi-Aquifer Systems Using GMS

Abstract: The Nubian Sandstone complex in the western desert is a part of the major regional Nubian aquifer system comprising West Africa. The different rock strata deposited in localities forming the units of the aquifer system. Farafra Oasis lies in the northern part of the Dakhla basin. In its southern region, the Nubian Sandstone (deep aquifer) is overlained by Dakhla shale but in the central and northern regions by fissured chalky limestone (shallow aquifer). The two overlaying aquifers in Farafra Oasis represent a typical hydrogeological model of a huge multi-layered artesian basin extending over the territory of Egypt. The Post Nubian aquifer played an essential role in the development of Farafra Oasis for a long time through the many springs issued from this aquifer. The rapid drilling process of deep wells started in 1960s led to stop flowing of many springs and wells plus the depletion in discharges and pressure of many others. Therefore, there is a real danger of either dewatering or increasing the water depths to uneconomic lifting depths for both the shallow and deep aquifers. A two-dimension flow model GMS (Groundwater Modeling System) was used to investigate this problem. Application of the present conditions indicated that drawdowns in the Post Nubian aquifer range from 5 m to about 9 m. The second scenario tries to sustain the groundwater utilities in the Post Nubian aquifer through a group of procedures. Accordingly, drawdowns are expected to range from 5 m to 8.6 m in the Post Nubian aquifer. According to this scenario, 3 m decline in the Nubian Sandstone aquifer followed by declining in the Post Nubian by about 1 m.

Natural Bio-Remediation of Arsenic Contamination: A Short Review

Abstract: The present short review is an attempt to explain the importance and uses of arsenic. It also explains different researches which have been conducted for treatment of arsenic contamination; particularly the botanical tools or the plants. The paper also deals with the future prospects of the topic, guiding the future aspects.

Marine Environmental Protection: A Highly Efficient Method of Degradation of Heavy Oil Pollution on Coastal Beaches

Abstract: Coastal oil pollution, especially occurring on coastal beach, is thorny issue when it comes to environmental restoration. Today, bioremediation is the current method used in treating beach oil pollution. Although it has undergone some improvements, this method still doesn't work very well. In this paper, a highly efficient procedure in bioremediation is studied. This method, using more varieties of microbes and water recirculation, may degrade heavy oil in a few days. Three sets are designed into this study. The method in Set 1 is a traditional degradation using a single microbe with only fertilizers and dispersant. The method in Set 2 is a highly efficient degradation process with more varieties of microbes, fertilizers, dispersant, fresh water recirculation and pumped-in air supplying. Set 3 is s control set which degrades heavy oil with the original microbe in beach sand only. Results of these experiments show that the process used in Set 2 will completely degrade heavy oil within 60 days. This is more efficient than by the traditional method as in Set 1, which takes more than 200 days.

Baseline Study of Drinking Water Quality - A Case of Leh Town, Ladakh (J&K), India

Abstract: Water is the vital resource on which life sustains and water becomes more valuable in this cold desert part of the northernmost region of India, called Ladakh which comprises of two districts, Leh and Kargil. Groundwater since ancient times in the form of springs provided ample water for the region and its contribution has increased manifold in the wake of recent spurt in bore well installations, especially, in Leh-Town. Due to increasing urbanization, with surge in a huge floating population in the absence of a sewerage link in summer tourism boom season, puts extra stress on the limited water resources of the area and with the rising living standards, grey and black water is being disposed off in the ground-pit or in septic tanks without any treatment. This may lead to pollution of groundwater resources especially, in the densely populated residential areas. For insuring sustainable development of groundwater, in the absence of any observation wells for constant monitoring of quality or quantity of groundwater and the unregulated installation of bore-wells makes this quality characterization very significant and helps in future management. The physico-chemical parameters like pH, electrical conductivity, turbidity, total dissolved solids, hardness, alkalinity, nitrates, fluoride, and chlorides were analyzed to meet the objective of the study. The results revealed that in general, the present status of groundwater quality is suitable for drinking purposes and out of 20 total samples evaluated, 75% of samples had NTU above desirable limit while 10% samples each recorded TDS and EC above desirable limits.

Zooplankton Diversity, Species Richness and their Distribution Pattern in Bhimtal Lake of Kumaun Region, (Uttarakhand)

Abstract: Bhimtal Lake situated in Uttarakhand, India, and has been devastated due to anthropogenic activities. In this study we examined the diversity and distribution pattern of zooplanktons in the Bhimtal Lake, along with evaluation of the relationships among different zooplankton groups and abiotic factors during the period September, 2013 to August, 2014. Sampling was done seasonally, during summer, winter and monsoon seasons, at three sites in Bhimtal lake. Sample analysis revealed the presence of 29 species of zooplankton including 16 species of Rotifers, 8 species of Cladocera and 5 species of Copepods. Rotifera group was the most dominant among all three groups. Positive co-relation was found between zooplankton growth with water temperature and pH while, there growth was adversely affected with increasing alkalinity, nitrates and dissolved oxygen. The diversity of Rotifers, Cladocera and Copepods were highest during summer, and was lowest during winter, while their density and biomass were found to be highest at the surface water during summer. It can be stated that the tropic nature of Bhimtal Lake may have been changed to mesotrophic conditions.

Event Based Flood Inundation Mapping Under the Impact of Climate Change: A Case Study in Lower Kelani River Basin, Sri Lanka

Abstract: The downstream low lying region of the Kelani River including the Colombo suburbs, experience severe inundation due to localized heavy rainfall events and high precipitation in the upper basin. Under the impact of climate change it is very likely that more frequent heavy rainfalls in tropics [1] will occur. Therefore it is extremely important to have a better understanding about future rainfall patterns and intensities in the basin and inundation extents of the low lying regions characterized by high population concentration and economic activities that form the suburbs of the commercial capital. This paper presents the extreme rainfalls occurrence potential and resulting flood inundation along the lower reach of Kelani River. Coarse grid atmospheric parameters provided by GCM models for A2 and B2 scenarios of IPCC [1] are downscaled to catchment scale by the application of Statistical Downscaling Model (SDSM). Flood discharge and inundation along the Kelani River reach below Hanwella was analyzed by the application of two-dimensional flood simulation model (FLO-2D). Inflow to the model at Hanwella, is estimated by the HEC- HMS model under future extreme rainfall events. Areas vulnerable for inundation under the above climate change scenarios are presented.

Biostimulator and Biodegradable Chelator to Pytoextract not Very Toxic Cu and Zn

Abstract: Taiwan spent too much expenditure to remove not very toxic metals Cu and Zn. The biosorption mechanism of metal removal (copper, Cu and zinc, Zn) by four phytoremediation macrophytes biomasses including sunflower (Helianthus annuus), Chinese cabbage (Brassica campestris), cattail (Typha latifolia), and reed (Phragmites communis) was investigated in this study. The primary objectives were exploring the potential of reusing these bio-wastes after harvesting from phytoremediation operations. Based on the surface area, zeta potential, scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) investigations, Chinese cabbage biomass presented the highest metal adsorption property while both cattail and reed revealed a lower adsorption capability for both metals tested. The equilibrium adsorption rate between biomass and metal occurred very fast during the first 10 min. The metal adsorption data were fitted with the Langmuir and Freundlich isotherms and presented that the Langmuir isotherm was the best fitted model for all biomass tested. All tested biomasses are fast growing plants with fairly high biomass production that are able to accumulate metals. The Langmuir model was used to calculate maximum adsorption capacity and related adsorption parameters in this study. The results revealed that the maximum metal adsorption capacity Qmax was in the order of Chinese cabbage (Cu: 2000; Zn: 1111 mg/kg)> sunflower (Cu: 1482; Zn:769 mg/kg)> reed (Cu: 238; Zn: 161 mg/kg)> cattail (Cu: 200; Zn: 133 mg/kg). The harvested sunflower, Chinese cabbage, cattail, and reed biomass possess the potential to be employed as biosorbents to remove Cu and Zn from aqueous solutions. Adsorption isotherms derived in this study might be crucial information for practical design and operation of adsorption engineering processes and prediction of relation between reused macrophyte biosorbents and heavy metal adsorbates.

Removal of Trihalo Methanes Using Activated Carbon Prepared from Agricultural Solid Wastes

Abstract: High chlorine dosages are used in some drinking water plants to overcome the deficiencies in the treatment to at least ensure a supply of microbiologically safe water to the population. This fact and the increment of natural organic matter (NOM) in the aquatic resources due to rainfall increases and anthropogenic activities are becoming a critical concern, due to the formation of chlorination by-products such as trihalomethanes (THM), which are carcinogenic substances. Egypt drinking water system using new treatments is essential to meet the quality guidelines. Trihalomethanes are carcinogenic by-products of disinfection that are present in drinking water. In the present research, adsorption was employed for the removal of THMs found in water supply systems. The effects of pH, contact time, adsorbents and adsorbate concentration on the adsorption system were investigated. The Langmuir and Freundlich adsorption isotherm models were used to analyse the resulting adsorption data. The kinetics of THM removal was found to follow the pseudo-second-order model rather than the Langmuir–Hinshelwood pseudo-first-order model.

Climate Change Impact on Design Storm and Performance of Urban Storm-Water Management System - A Case Study on West Central Mountain Drainage Area in Canada

Abstract: A number of future climate projections indicate a likelihood of increased magnitude and frequency of hydrological extremes for many regions around the world. The urban storm-water management infrastructures are designed to mitigate the effect of extreme hydrological events. Changes in extreme rainfall events will have a significant implication on the design of storm-water management infrastructures. This study assessed the potential impact of changed rainfall extreme on drainage systems in the West Central Mountain drainage area located in Southern Ontario, Canada. First, the design storms for the study area were calculated from observed rainfall data and the North American Regional Climate Change Assessment Program (NARCCAP) climate simulations based on SRES A2 Scenario. Frequency analysis was performed on the annual maximum time series data by using the best fitted distribution among twenty seven distributions. The Pearson chi-square test and Kolmogorov-Smirnov were used to test the goodness of fit of each distribution. The results show that L-moment Pareto distribution was selected the most often for data from six RCM+GCM pairs. Overall increase of storm depth in the future is highest when the distributions were identified by the Kolmogorov-Smirnov test. The design storm depths calculated from the observed and climate model simulated data were used as input into an existing PCSWMM model of the study area for flow simulation and hydraulic analysis for the storm-water management system, specifically storm sewer and detention pond. The results show an increase in design storm depths under projected climatic change scenarios that suggest an update of current standard for designing both the minor system and detention pond in the study area. The assessment results of storm water management infrastructures indicate that performance of the detention pond as well as the storm sewer network will deteriorate under future climate condition.

Water Quality Assessment and Apportionment of Pollution Sources of Selected Pollutants in the Min Jiang, a Headwater Tributary of The Yangtze River

Abstract: This paper analyzed the spatial-temporal variations of surface water quality along the middle and lower reaches of the Min Jiang between 2003 and 2012 and investigated its pollution sources by analyzing the data from 4 water quality monitoring stations. The results showed that surface water quality was higher polluted in the middle reaches of the Min Jiang than that in the lower reaches and its tributary. Seasonal and spatial differences were found for DO, CODmn and NH3-N, whereas for TP the differences were mainly due to the water quality station. The level of organics (CODmn) was higher in summer (high flow period), and the level of NH3-N was higher in winter (low flow period). In the middle reaches of the Min Jiang, point sources (from wastewater treatment plants and industrial effluents) were found to be the dominant inputs of organics (CODmn) and nutrients (NH3-N and TP) to river. In the lower reaches of the Min Jiang, diffuse sources (from agricultural fertilizer, soil erosion, etc.) were the dominant contributor of organics and TP to river, while point sources were the dominant input of NH3-N. In tributary, diffuse sources were the dominant organics and TP input, both point and diffuse sources were dominant NH3-N inputs. Overall, these results reinforced the notion that pollution control by periods and regions was important for effective water quality management, and it is necessary to enhance the treatment of industrial effluent, to strictly carry out the discharge standard for water pollutants and the total amount control system, to incorporate NH3-N in the total amount control system in the Min Jiang.

New Economic Policies: Instruments for Water Management in Lebanon

Abstract: Social, economic and environmental aspects should be taken into consideration for IWRM implementation in Lebanon. This would be helpful to formulate policies required for improving water sector. Likewise many countries, Lebanon do not implement water policies on the formal level. This is critical since policies are initiative for legislation, strategic planning and operational management. Hence, water resources in Lebanon are threatened by population growth and climatic variability and imbalanced supply/demand. Thus, the interrelation between supplier and consumer should be harmonized since there is large amount of water is lost due non-uniform water supply and partitioning approaches, besides lack of awareness and absence of wise-use of water resources. Therefore, economic policies should be adopted in Lebanon and water pricing must be set to give incentives to user for efficient water use in their various applications. Thus, treating water as an economic good recognizes that water carries an opportunity cost. This paper presents the existing economic status of water in Lebanon in the absence of legal economic policies. It, therefore, extends new Economic Policies Instruments (EPIs) is required for better IWRM.

Evaluating Multi-Scale Flow Predictions for the Connecticut River Basin

Abstract: This case study evaluates a computationally efficient distributed hydrological model, named Coupled Routing and Excess Storage (CREST), for flood modeling of basins in the Connecticut River Basin (CRB). Simulation of discharges is performed by forcing CREST with a long record (eight years) of high resolution radar-rainfall data and potential evapotranspiration maps derived from the North American Regional Reanalysis. The model performance is evaluated against observed streamflows obtained from United States Geological Survey gauging stations at outlet and interior points of various CRB sub-basins. CREST parameters were calibrated based on a three year record (2005-2007) and validated for the remaining data period (2003-2004 and 2008-2009). The model performance evaluation is based on different metrics, including the Nash-Sutchliffe Coefficient of Efficiency (NSCE), Mean Relative Error (MRE), Root Mean Square Error (RMSE), and Pearson Correlation Coefficient (PCC). The analysis shows that CREST slightly underestimated the peak flows, but exhibited a generally good capability in simulating the stream flow variability for the CRB basins. Specifically, NSCE, MRE, RMSE, and PCC values of hourly flow simulations varied from 0.31 to 0.58, -0.06 to 0.13, 61 to 121 (mm) and 0.60 to 0.83, respectively. At daily time scale the performance metrics exhibited improved values indicating that CREST has sufficient accuracy for long term multi-scale hydrologic simulations.

Estimating mean long-term hydrologic budget components for watersheds and counties: An application to the commonwealth of Virginia, USA

Abstract: Mean long-term hydrologic budget components, such as recharge and base flow, are often difficult to estimate because they can vary substantially in space and time. Mean long-term fluxes were calculated in this study for precipitation, surface runoff, infiltration, total evapotranspiration (ET), riparian ET, recharge, base flow (or groundwater discharge) and net total outflow using long-term estimates of mean ET and precipitation and the assumption that the relative change in storage over that 30-year period is small compared to the total ET or precipitation. Fluxes of these components were first estimated on a number of real-time-gaged watersheds across Virginia. Specific conductance was used to distinguish and separate surface runoff from base flow. Specific-conductance (SC) data were collected every 15 minutes at 75 real-time gages for approximately 18 months between March 2007 and August 2008. Precipitation was estimated for 1971-2000 using PRISM climate data. Precipitation and temperature from the PRISM data were used to develop a regression-based relation to estimate total ET. The proportion of watershed precipitation that becomes surface runoff was related to physiographic province and rock type in a runoff regression equation. A new approach to estimate riparian ET using seasonal SC data gave results consistent with those from other methods. Component flux estimates from the watersheds were transferred to flux estimates for counties and independent cities using the ET and runoff regression equations. Only 48 of the 75 watersheds yielded sufficient data, and data from these 48 were used in the final runoff regression equation. Final results for the study are presented as component flux estimates for all counties and independent cities in Virginia. The method has the potential to be applied in many other states in the U.S. or in other regions or countries of the world where climate and stream flow data are plentiful.

Characterization of a Typical Mediterranean Watershed Using Remote Sensing Techniques and GIS Tools

Abstract: Geographic Information Systems (GIS) were used to establish an information data base to characterize a watershed in Northern Greece, analyze the distribution of the drainage network according to the different characteristics of the watershed using a drainage density index based on GIS. The drainage network was delineated from ASTER GDEM and Landsat-8 OLI data. Digital image processing was based on enhancement techniques. GIS characterized the watershed easily and efficiently. The drainage density index, based on the number of pixels, was appropriate for analyzing the distribution of the drainage network in relation to other characteristics of the watershed. The possibility of using GIS to generate buffer zones around linear and area features helped to quantify sensitive areas close to streams. The problem of cell resolution was overcome by reference to the mapping scale and other factors. Landsat-8 OLI data gave promising results, closely accurate to those from a 1:50,000 topographic maps. The number of streams and total stream lengths of all orders from ASTER GDEM data were higher than from the other sources. Geometric characteristics of the watershed derived from ASTER GDEM data were almost the same as from the 1:50,000 topographic maps. Best results were from a new band index based on Bands 2 and 5. Both techniques, GIS and Remote Sensing, are suitable for application to watershed management in the Mediterranean region.

Phenol adsorption onto various soil composite membranes: insight into process kinetics, modelling and optimisation using response surface methodology.

Abstract: The present study investigates the potential of soil and soil composites for removal of phenol from solution on a comparative scale. Different experimental parameters were optimized with a novel approach of response surface methodology (RSM) and a central composite design (CCD) for achieving maximum efficiency. Maximum adsorption efficiency (1.44 mg g-1) was obtained at initial pH 5.5, an adsorbent dosage of 7.5 g L-1 and a treatment time of 32.5 mins at a temperature of 313 K as predicted by the RSM design. The phenomenon best fitted the Temkin isotherm at different temperatures. The process was guided by the pseudo-secondorder kinetic model and was analyzed to be spontaneous, endothermic and chemisorption in nature. Characterization of soil particles using Scanning Electron Microscopy and Fourier Transform Infrared Spectroscopy showed the changes in its structure and surface morphology both before and after use and explained it’s prospective as a good and environmentally benign adsorbent in very low quantities. Hence, this adsorbent can be implemented as an efficient liner material for the removal of phenol and phenolic compounds from wastewater.

Fluoride Concentration in Drinking Water of Lucknow City, India: A Case Study

Abstract: Drinking water Samples were collected from different localities of Lucknow city, Capital of Uttar Pradesh State, India for the estimation of Fluoride content. Boring water as well as supply water of Municipal Corporation was collected for the present study. It was found that almost all the studied samples had fluoride concentration within the acceptable limit and no substantial difference in fluoride concentration was found in all the samples except the samples from Bhola purva, Bakshi ka taalab area. Water collected from this area has more than 1.0 ppm (acceptable limit in India) of fluoride.

Shallow groundwater conservation based empowerment and its influence factors by groundwater user farmers in Takalar Regency.

Abstract: This study is an initial stage in an effort to conserve groundwater by employing skills and self-reliance of groundwater user farmers where the groundwater is utilized to irrigate farm. Before carrying out community empowerment, specifically for marginal community, the researcher shall be able to recognize some factors that affect target's empowerment. Accordingly, empowerment model formulation which can be made representatively shall in conformity with reality to empowered target community. To examine level of influence of every observed factor in this study, it applies instrument through Gutmann scale. Scales of applied instrument in the study is answers of YES or NO. The instrument is adapted by vary educational background of the farmers. For all identified factors in the study, there are 6 factors that affect significantly groundwater user farmer empowerment level in their effort to conserve groundwater independently and collectively. Factors indicating significant influence are: (1) agricultural input, (2) environmental potential, (3) technical aid, (4) farmer organization, (5) farmers' rights and (6) democratization of farmers.

The Need to Enforce Minimum Environmental Flow Requirements in Tanzania to Preserve Estuaries: Case Study of the Mangrove-Fringed Wami River Estuary

Abstract: The importance of restoring and maintaining environmental flows for sustaining the ecosystem integrity of rivers and estuaries has been recognized and given proper attention in policies and legal frameworks in many countries including Tanzania. The Wami River estuary is small but it plays a vital role in processing riverine nutrients, in trapping sediment, in recycling nutrients in the mangroves, and in supporting the ecology of the Saadani National Park and the livelihood of the local communities. The proper functioning of this estuary to a large extent depends on adequate supply of freshwater flows. Our studies reveal that currently the estuary is ecologically healthy but it is threatened by both increasing sedimentation and declining freshwater flow caused by decreasing rainfall - possibly linked with climate change - and by increasing water demand in the watershed for artisanal and large scale agriculture and irrigation schemes. Environmental flow assessment for the Wami River (with exclusion of estuary) has been done and the minimum flows were recommended. However, like in many other rivers in the country, effective implementation of recommended environmental flows remains to be a challenge. In order to maintain a healthy estuarine ecosystem in the future, it is the obligation of the WRBWO now to stick to and enforce the recommendations of its own environmental flow assessment to regulate water usage in the watershed. A similar recommendation also holds for all other rivers and estuaries in Tanzania.

Evidences of Spatiotemporal Climate Change and its Mitigation in Ethiopia

Abstract: The change detection at country level was unidirectional trend analysis between two time periods of 1946 and 2006. Temperature shows increasing trend but rainfall shows fluctuation. Point analysis of climate data at local level (1980-2010), Mekelle town, Northern Ethiopia, one of the semi-arid areas, showed that minimum temperature for the months of October through January had an increasing trend while maximum temperature for the hot season (April- June) and annual rainfall had no significant trend and were inconsistent. Region-specific detailed and seasonal climate studies are needed and to be integrated with local context of agriculture, livelihoods, forecasts and development plans for effective Early Warning Systems to utilize climate potentials and minimize natural disasters. This study serves as a milestone for further detailed agroclimatic and sector based analysis of spatio-temporal climate change patterns, impact assessment and adaptation and mitigation strategies. Massive sustainable local community based natural resource management efforts have been undertaken and there had been lots of success stories in the last 25 years. SLM practices constitute key adaptation and mitigation measures by resulting in reduced soil erosion, improved water retention, and improved land productivity. Rainfall generally shows declining trend with exception to Northern Region for the period of 1946 to 2006. Moist areas of Western and South Western Ethiopia are showing negative trend of rainfall which indicates that their forest covers have been deteriorating through time. However, the drier Northern Ethiopia region area shows positive (upward) trends owing to massive environmental rehabilitation and restoration of degraded lands into productive lands in the last 25 years. The public investment in Northern Ethiopia region on environmental rehabilitation has resulted in rehabilitated environment and contributed to reversing adverse effects of climate change. These local actions taken as adaptation and mitigation strategies against global warming should be encouraged, globally recognized, and rewarded.

Impact of Caspian Sea Drying on Indian Monsoon Precipitation andTemperature as Simulated by RegCM4 Model

Abstract: This study using a regional climate model, ICTP-RegCM4.0 simulations examines the impact of drying and shrinking of Caspian Sea on Indian summer and winter monsoon, particularly on precipitation over northern plains of India due to Western disturbances. Shrinking of Caspian Sea is a man-made catastrophe with serious environmental implications. To perform the sensitivity experiment the original landuse map in the model is altered where the “Caspian Sea” in Central Asia is changed to “semi-desert” in place of “inland water” type of vegetation. The model is forced with NNRP2 boundary conditions for year 2009, 2010. Analysis of sensitivity experiment output w.r.t baseline experiment says that rainfall over Northern India decreases (significant at 5% level), during the months of winter season (months of October to March) primarily from Western disturbances originating from Central Asia and Caspian Sea region. Also, it is found that minimum (maximum) temperature decreases (increases) particularly over Indian region during October to March and June to September. During June to September (for year 2009, 2010) from model simulations results it is found that over Central Asia (India) air temperature extending upto 700hPa increases (decreases).