Evaluation Of Groundwater Resources Research Articles

Evaluation of groundwater resources in the Southern Tihama plain, Saudi Arabia

In the absence of permanent rivers, groundwater is one of the major water resources in Southern Tihama plain, in the Southwestern Saudi Arabia. Hydrogeological investigation, as well as hydrogeochemical analyses, of 272 groundwater samples was performed to evaluate groundwater resources of shallow alluvial aquifer and their quality for different purposes in the Southern Tihama plain. Hydrogeological investigation revealed that groundwater occurs mainly in alluvium deposits under free water table conditions that range between 9 and 33 m. The calculated hydraulic gradient is inclined towards the west and southwest direction, ranging from 0.001 to 0.005, and soil infiltration rate of coastal plain soils is higher than other soil types. Hydrochemical analysis results indicate that groundwater type is mainly sodium chloride reflecting high amount of minerals. Groundwater in Tihama plain is not suitable for direct drinking and domestic purposes; therefore, it needs a proper treatment to remove high salinity and chloride concentrations. Result also shows that most of the groundwater has high salinity and low sodium hazard, suggesting little danger of exchangeable sodium. Other quality indices such as salinity, chloride, sulfate, and alkalinity range from suitable to high restricting water suitability for some industrial purposes without special treatment or mixing with low saline water.

Bootstrap Calibration and Uncertainty Estimation of Downhole NMR Hydraulic Conductivity Estimates in an Unconsolidated Aquifer

Characterization of hydraulic conductivity (K) in aquifers is critical for evaluation, management, and remediation of groundwater resources. While estimates of K have been traditionally obtained using hydraulic tests over discrete intervals in wells, geophysical measurements are emerging as an alternative way to estimate this parameter. Nuclear magnetic resonance (NMR) logging, a technology once largely applied to characterization of deep consolidated rock petroleum reservoirs, is beginning to see use in near-surface unconsolidated aquifers. Using a well-known rock physics relationship-the Schlumberger Doll Research (SDR) equation--K and porosity can be estimated from NMR water content and relaxation time. Calibration of SDR parameters is necessary for this transformation because NMR relaxation properties are, in part, a function of magnetic mineralization and pore space geometry, which are locally variable quantities. Here, we present a statistically based method for calibrating SDR parameters that establishes a range for the estimated parameters and simultaneously estimates the uncertainty of the resulting K values. We used co-located logging NMR and direct K measurements in an unconsolidated fluvial aquifer in Lawrence, Kansas, USA to demonstrate that K can be estimated using logging NMR to a similar level of uncertainty as with traditional direct hydraulic measurements in unconsolidated sediments under field conditions. Results of this study provide a benchmark for future calibrations of NMR to obtain K in unconsolidated sediments and suggest a method for evaluating uncertainty in both K and SDR parameter values.

Development of Rainfall Recharge Model for Natural Groundwater Recharge Estimation in Godagari Upazila of Rajshahi District, Bangladesh

Estimation and forecast of groundwater recharge and capacity of aquifer are essential issues in effective groundwater resource management in Bangladesh. Godagari Upazilla is located in High Barind Tract situated in the northwestern part of Bangladesh. A typical dry climate with comparatively high temperature prevails in this Barind area. It is particularly significant in regions with large demands for groundwater supplies to meet irrigation needs, where such resources are the key to economic growth. However, the rate of aquifer recharge is one of the most complicated factors to assess in the evaluation of groundwater resources. Assessment of recharge, by whatever method, is normally subject to large uncertainties and errors. In this paper, an attempt has been taken to develop a rainfall recharge model by non-linear regression technique to determine groundwater recharge using only annual rainfall data in Godagari Upazilla based upon groundwater balance study carried out for a number of years. It was also proven that the developed model provided an accurate estimation for similar projects

Evaluation of Groundwater Resources of an Alluvial Pluvial Fan in Hebei Province, China Using Hydrological Budget Method

Estimating groundwater recharge and groundwater discharge are key components in determining the sustainable utilization of groundwater resources. Infiltration recharge by rainfall and irrigation water recharge are the main supply of groundwater in the study area. In this paper, based on the hydrological budget method, we analyzed, the utilization of groundwater resources, calculated, the recharge and excretion of groundwater in the study area from 1995 to 2012, and finally, pointed out the groundwater level is mainly affected by the irrigation water. Therefore, readjustment of the structure of plant is to ensure the ecological environment, utilize rationally the groundwater resources and achieve the goal of sustainable use of groundwater resources.

Delineation of groundwater potential zones in the crystalline basement terrain of SW-Nigeria: an integrated GIS and remote sensing approach

Due to complex and erratic nature of groundwater occurrences in crystalline basement terrains, groundwater development in form of boreholes/wells without the necessary pre-drilling hydrogeological investigations usually results in failure. Therefore, there is the need for adequate characterization of aquifers and delineation of groundwater potential zones in such crystalline basement setting. This study employed the integration of multi-criteria decision analysis (MCDA), remote sensing (RS) and geographical information system (GIS) techniques to delineate groundwater potential zones in crystalline basement terrain of SW-Nigeria and validation of the result with existing borehole/well yield data. The study approach involved integration of nine different thematic layers (geology, rainfall geomorphology, soil, drainage density, lineament density, landuse, slope and drainage proximity) based on weights assignment and normalization with respect to the relative contribution of the different themes to groundwater occurrence using Saaty’s analytic hierarchy approach. Following weigh normalization and ranking, the thematic maps were integrated using ArcGIS 10.0 software to generate the overall groundwater potential map for the study area. The result revealed that the study area can be categorized into three different groundwater potential zones: high, medium and low. Greater portion of the study area (84,121.8 km2) representing about 78 % of the total area, fall within the medium groundwater potential zone which are generally underlain by medium-porphyritic granite, biotite-hornblende granite and granite gneiss bedrock settings. About 18,239.7 km2 (17 %) fall under high groundwater potential zone which are characterized by weathered/fractured quartzite, quartz-schist, amphibolite schist and phyllite bedrock settings. However, areas of low groundwater potentials constitute only 3 % (3,416.54 km2) of the total study area and are mostly underlain by migmatite, banded and augen gneiss bedrock settings. Subsequent validation with boreholes/well yield data revealed a good correlation with respect to the observed groundwater potential zonation. Wells/boreholes with yields greater than >150 m3/day are generally characteristic of areas with high groundwater potential while those with yields of 75–150 and <75 m3/day are typical of areas with medium and low groundwater potentials, respectively. The validation clearly highlights the efficacy of the integrated MCDA, RS and GIS methods employed in this study as useful modern approach for proper groundwater resources evaluation; providing quick prospective guides for groundwater exploration and exploitation in such crystalline basement settings.

The hydraulic conductivity field and groundwater flow in the unconfined aquifer system of the Keta Strip, Ghana

This study investigates the hydraulic conductivity field and the groundwater flow pattern as predicted by a calibrated steady state groundwater flow model for the Keta Strip, southeastern Ghana. The hydraulic conductivity field is an important parameter in evaluating aquifer properties in space, and in general basin-wide groundwater resources evaluation and management. This study finds that the general hydraulic conductivity of the unconsolidated unconfined aquifer system of the Keta Strip ranges between 2m/d and 20m/d, with an average of 15m/d. The spatial variation in horizontal hydraulic conductivity appears to take the trend in the variations in the nature of the material in space. Calibrated groundwater recharge suggests that 6.9–34% of annual precipitation recharges the shallow aquifer system. This amount of recharge is significant and suggests high fortunes in terms of groundwater resources development for agriculture and industrial activities in the area. A spatial distribution of groundwater recharge from precipitation is presented in this study. The spatial pattern appears to take the form of the distribution in horizontal hydraulic conductivity, and suggests that the vertical hydraulic conductivity takes the same pattern of spatial variation as the horizontal hydraulic conductivity. This is consistent with observations in other areas. The resulting groundwater flow is dominated by local flow systems as the unconfined system is quite shallow. A general northeast – southwest flow pattern has been observed in the study area.

Assessment of surface and subsurface waterlogging, water level fluctuations, and lithological variations for evaluating groundwater resources in Ganga Plains

In the present study, the multi-temporal satellite images of IRS P6 LISS III were used to map waterlogging dynamics over different seasons. An area of 594.36 km2 (6.75%) and 4.17 km2 (0.04%) was affected by surface waterlogging during pre and postmonsoon season, respectively. The average annual groundwater level fluctuations were calculated using 18 years (1990–2007) pre and postmonsoon groundwater level data to identify the areas which are under groundwater induced waterlogging conditions. The soil map clearly indicates that salinity and sodicity exhibit the highest severity and occur in areas with shallow groundwater levels. The hydrogeomorphical units mapped using IRS P6 LISS III satellite images are flood plain, alluvial plain, paleochannels, and oxbow lakes. The study revealed that 44.65% areas have very good to excellent groundwater resources. The litholog data clearly indicate an alternating sequence of clay and sand in which deep aquifers made up of coarse sand would be best suited for adequate water supply and good groundwater quality. The integrated study utilizing digital spatial data pertaining to waterlogging, soil salinity, water level fluctuation, and lithological variation proved that planning of any surface and subsurface water resources development activity should be taken up after assessments of said parameters.

Hydrogeomorphological mapping as a tool in groundwater exploration

Hydrogeomorphological maps have a useful importance in exploration hydrogeology, engineering geosciences, geotechnical engineering and planning. The role of geomorphology is decisive to correctly evaluate groundwater resources. Hard-rock hydrogeological systems commonly exhibit complex geological and morphological features. This study highlights methodological guidelines for the preparation of hydrogeomorphological maps to support groundwater conceptual modelling, as well as for hydrogeological surveys and environmental sustainability issues. Cartographic techniques can provide an accurate way of improving the knowledge on groundwater and surface water circulation and the overall functioning of aquifer systems. A comprehensive evaluation of these subjects has been completed during the preparation of hydrogeomorphological maps for the Alardo groundwater system and Touca hydromineral system, both located on Gardunha mountain in Central Portugal. Thematic maps were prepared mainly from satellite imagery analysis, topographic, geological, geomorphological and hydrogeological field surveys. This information was presented to outline the recharge potential areas and infiltration rates. The paper also contributes to hydrogeomorphological mapping design and the conceptual model of groundwater in fractured hard-rock aquifer systems.

Groundwater Flow Simulation and its Application in Groundwater Resource Evaluation in the North China Plain, China

AbstractThe purpose of this study is to establish a 3D groundwater flow modelling for evaluating groundwater resources of the North China Plain. First, the North China Plain was divided into three aquifers vertically through a characterization of hydrogeological conditions. Groundwater model software GMS was used for modeling to divide the area of simulation into a regular network of 164 rows and 148 lines. This model was verified through fitting of the observed and the simulated groundwater flow Gelds at deep and shallow layers and comparison between the observed and simulated hydrographs at 64 typical observation wells. Furthermore, water budget analysis was also performed during the simulation period (2002–2003). Results of the established groundwater flow model showed that the average annual groundwater recharge of the North China Plain during 1991 to 2003 was 256.68×108 m3/yr with safe yield of groundwater resources up to 213.49×108 m3/yr, in which safe yield of shallow groundwater and that of deep groundwater was up to 191.65×108 m3/yr and 22.64×108 m3/yr respectively. Finally, this model was integrated with proposal for groundwater withdrawal in the study area after commencement of water supply by South‐North Water Transfer Project, aiming to predict the changing trend of groundwater regime. As indicated by prediction results, South‐North Water Transfer Project, which is favorable for effective control of expansion and intensification of existing depression cone, would play a positive role in alleviation of short supply of groundwater in the North China Plain as well as maintenance and protection of groundwater.

Hydrochemical and stable isotopic characterization of shallow groundwater system in the crystalline basement terrain of Ekiti area, southwestern Nigeria

Assessments of hydrochemical quality and recharge source are critical components of sustainable groundwater resources evaluation and management, especially in complex weathered/fractured crystalline bedrock terrains. Assessment of the weathered/fractured basement aquifer of Ekiti area, SW-Nigeria was undertaken with emphasis on hydrochemical quality and stable isotope characterization of shallow groundwater system. The study approach involved field sampling and in situ measurements of physico-chemical parameters followed by hydrochemical and stable isotope analyses of the water samples. In situ measurements revealed EC value of 43–995 μS/cm (av 431.96 μS/cm) and total hardness of 31.3–295.1 mg/L. The pH of the water sample ranged from 7.0 to 8.9 (av 8.00). The concentrations of the major cations are in the order of Ca2+ > K+ > Na+ > Mg2+ with their respective average values of 33.35, 25.61, 24.91 and 8.7 mg/L respectively while that of the anions are in the order of HCO3− > Cl− > SO42− > NO3− with their respective average values of 165.44, 31.85, 21.27 and 5.44 mg/L respectively. However, the results of stable isotope analyses revealed δ18O value of −4.2 to −2.1 ‰ and δD of −22.3 to −10.2 ‰, suggesting meteoric water source (recent precipitation water recharging the associated shallow basement aquifer) while the estimated deuterium excess of 6.80–11.00 ‰ (av 9.6 ‰) suggested little or no imprint of kinetic evaporation. Furthermore, the overall hydrochemical profiles revealed the main hydrochemical facies as Ca(Mg)-HCO3 (dominant) and Na(K)-HCO3 (minor) water types which can be attributed to dissolution of minerals in the various rock units in the study area. Conclusively, the overall hydrochemical and stable isotope evaluations revealed a recharge predominantly derived from meteoric (rainfall) source while the corresponding low TDS is a reflection of low water–rock interaction and limited migratory history of the shallow groundwater system in the study area.

Comparative Analysis of Empirical Formulae Used in Groundwater Recharge in Ogun – Oshun River Basins

Quantification of the rate of natural groundwater recharge is a pre-requisite for efficient groundwater resource management. It is particularly important in regions with large demands for groundwater supplies, where such resources are the key to economic development. However, the rate of aquifer recharge is one of the most difficult factors to measure in the evaluation of groundwater resources. Estimation of recharge, by whatever method, is normally subject to large uncertainties and errors. In this paper, an attempt has been made to derive groundwater recharge from rainfall in ogun-oshun river basin using three empirical formulae and they include modified chaturvedi formula (1936) and Krishna Rao (1970) in Kumar, (2009); Kumar and Seethapathi (2002). Results from these three empirical formulae were compared using line graph, inter-item correlation and one way analysis of variance (ANOVA). A correlation coefficient of the range of 0.99-1.0 exist between each formula, and the rejection the null hypothesis that the means of the three formulae are not different from each other leading to the conclusion that any of the Research Article Oke et al.; JSRR, Article no. JSRR.2013.017 693 formula can be used for recharge estimations.

Development of regional hydrogeological mapping in Russia

The subject of regional hydrogeology is best described as the subject of regional patterns in groundwater occurrence, formation and evolution. This discipline is a branch of hydrogeology and includes the following components: structural geological zoning, hydrogeological classification of cross-sections, groundwater classification, hydrogeological zoning based on groundwater hydrogeodynamics, hydrochemistry, temperature and other parameters, palaeohydrogeological reconstructions, regional mapping and regional evaluation of groundwater resources. Regional hydrogeology deals with groundwater formation, occurrence, evolution, distribution, and patterns within big hydrogeological structures in regions, continents and the entire Earth. Regional hydrogeological mapping, being a component of regional hydrogeology, is also an effective tool in studying regional groundwater patterns and resources.

Potential impacts of climate change and variability on groundwater resources in Nigeria

Climate change observed over the past decades has been consistently associated with modifications of components of the hydrological systems such as precipitation patterns, sea surface temperature, accelerated melting of glacier and ice caps, soil temperature and moisture, surface runoff and stream flow. Such changes are known to influence subsurface hydrological systems, which could lead to changes in groundwater recharge, discharge and storage of many aquifers. Although, there are uncertainties in the characterisation of climate change induced groundwater impacts due to largely multi-scale local and regional heterogeneity, there is need to evaluate groundwater resources, quality and vulnerability to climate change and variability. This paper attempts to assess the potential impacts of climate change and variability on groundwater resources availability and sustainability in Nigeria.

Groundwater Flow Simulation and Resource Evaluation of the Affected Zone along the Yellow River (Henan Section)

The purpose of this paper is to build a three-dimensional groundwater flow model of the affected zone along the Yellow River, and to conduct equilibrium analysis and resource evaluation to the groundwater of the research area according to the simulation results. In the beginning, the groundwater flow numerical simulation model (1999.1-2009.12) is established and verified through the GMS software on the basis of the establishment of hydrogeological conceptual and mathematical models. Results of the simulation model show that the perennial average of the resources of shallow groundwater recharge is 29.32×108m3/a, the average recharge modulus is 22.35×104m3/km2•a and the safe yield of groundwater resource is 27.04×108m3/a.

Evaluation of Groundwater Resources of the Middle Niger (Bida) Basin of Nigeria

The Middle Niger Basin lies in the sedimentary terrains of the middle part of Nigeria. It has an area coverage of about 27,000km<SUP>2</SUP>. The area falls under the middle Nigeria climatic belt which is mainly tropical with an average rainfall of about 1250mm. This paper evaluates the hydrogeological potential of the terrain. The methods of investigation include analysis of meteorological, drilling, pumping tests and water quality data. A total of about 50 boreholes located in the area were selected for study. Results of the analyses of the data showed that groundwater occurs both in confined and semi-confined conditions. Depth to water rarely exceeds 50m, though in some few cases may be over 70m. Averagely, well yield varies between 1.08 and 19m<SUP>3</SUP>/hr. Transmissivity values obtained using various methods vary between 1.365 and 393m<SUP>2</SUP>/day. Hydrochemical analyses of groundwater samples showed poor mineralization with low TDS (Total Dissolved Solids) rarely over 300mg/l. The water is fresh, soft and free of chemical pollution and therefore suitable for many purposes.

Comparison of Groundwater Flow Systems under the Control of Different Aquifer Structures

The structure of groundwater flow system is the core of study of groundwater system and the base of evaluation of groundwater resources. The control role of aquifer system to groundwater flow system is a key of study of the structure of groundwater flow system. The groundwater systems of the Ordos basin are analyzed as a case study. The control role of aquifer system to groundwater flow system is studied by comparison of groundwater flow systems under the control of different aquifer structures in 2-D profile numerical model. The research shows that the groundwater flow systems of the Ordos basin have the multilayer structure characteristics. The groundwater flow systems in the north of the Ordos basin show a cross-formational multi-hierarchy nested flow pattern in the northern aquifer systems without regional impermeable layer where the hydraulic connection between aquifer layers is closely. While, the hydraulic connection is discontinuous in the southern aquifer systems because there are regional impermeable layers in the aquifer systems. The groundwater flow systems in the south of the Ordos basin show a follow-formational flow pattern.

Research on Numerical Stimulation of Water Resources of Bang River by Finite Volume Method

In order to find out Bang river of hydrogeological conditions in Liandi beach, Evaluation of groundwater resources, Put forward the scientific and reasonable layout of new Wells. This paper will be for the finite volume method is applied to the underground water resources evaluation and numerical simulation research of Yellow River xiaolangdi key water control project in Bang river zone . As the Bang river groundwater flow problems put forward a kind of high precision and simple new method. The study on speeding up the construction progress and safeguard the social stability has the important practical significance. The calculation results show that the finite volume method advantages of flexible meshing, geometric error is small, easy to deal with natural boundary conditions, to maintain the quality and higher accuracy. The calculation and evaluation of groundwater resources has important application value.

Strategic groundwater resources planning in arid regions

A strategic approach is presented for future groundwater reservoir planning in arid regions where the evaluation of groundwater resources is restricted by scarcity of rainfall, data paucity, restrictive and unrepresentative methodologies, weak economies, almost nonexisting management and optimization programs, frequent groundwater quality variables along short distances, etc. This paper explains the necessary steps in preparing an effective strategic planning program that is expected to provide all the necessary data for identifying alternative solution scenarios especially in arid regions. It is shown on the basis of available scarce data that the risk model of these factors appears as the logarithmic normal probability distribution. The basic decision variables in groundwater storage and recharge planning are furnished with application to Wadi Fatimah in the western central part of the Kingdom of Saudi Arabia along the Red Sea coast. The approach given in this paper provides a basic example for future groundwater reservoir strategic use and management studies in the Kingdom in particular and in any part of the arid regions of the world, in general.

The spatial variability of streambed vertical hydraulic conductivity in an intermittent river, northwestern China

Streambed vertical hydraulic conductivity (K) plays an important role in river water and groundwater interaction. The K at the ten transects (Ts1–Ts10) at the Donghe River (an intermittent river) in the Ejina Basin, northwestern China, was measured to investigate its spatial variation. Based on the sediment characteristics and vertical hydraulic conductivity of the riverbed, the entire riverbed of the Donghe River could be divided arbitrarily into two parts: an upper part (starting at Ts1 and ending at Ts9, without an obvious and continuous clogging layer) and a lower part (the remaining riverbed, with an obvious and continuous clogging layer). In the upper part, although the K varied with depth within the 0–30 cm layer, the variability with depth could be ignored in practice. The arithmetic mean K of the upper part ranged from 12 to 27.6 m/day, three orders of magnitude larger than that of the lower part (0.06 m/day). The change of K along the river cross section was significant, and larger values of K often occurred in the parts of the channels with greater water depth. However, there were no consistent patterns of the variability of K at transects across the river, which was influenced by the variation in streambed characteristics. The results could be useful for the estimation of groundwater recharge from river and groundwater resources evaluation in the Ejina Basin.

Evaluation of groundwater resources for drinking and agricultural purposes, Abar Al Mashi area, south Al Madinah Al Munawarah City, Saudi Arabia

A hydrogeochemical study was conducted on the groundwater of south Al Madinah Al Munawarah City, Saudi Arabia, to assess the quality of groundwater for drinking and irrigation uses. Groundwater samples have been collected and analyzed for major and some trace constituents from the study area. The nitrate concentration in most groundwater samples of the study area exceeded the safe limits for drinking purposes, whereas the concentrations of phosphate, boron, and trace constituents were below the maximum permissible limit for drinking purposes; Cr in two samples showed high content over the recommended limits of drinking purposes. Uncontrolled abstraction of groundwater in Abar Al Mashi area caused many environmental problems including water resource depletion and contamination. Correlations between chloride and major ions were positive and may be attributed to impact of agricultural activities on groundwater chemistry. Groundwater of the study area was classified into six water types. The chemical water types of groundwater in the study area contain CaHCO3 in the eastern and southeastern parts and NaCl in western and northwestern parts, reflecting different land use characteristics and pollution sources. Piper diagram showed that almost all the samples fall in one zone, indicating similar chemical signature. Groundwater can be used safely for drinking with special treatments to eliminate the effect of increased concentrations of total dissolved solids, nitrate, and chromium. The groundwater of the study area can be used safely for irrigation on clay soil; however, specific crops should be selected according to their salt tolerance.