Hand-dug Wells Research Articles

EFFECT OF WASTE DUMPSITE ON GROUNDWATER QUALITY OF A SHALLOW AQUIFER IN PORT HARCOURT, SOUTH-EASTERN NIGERIA

The study assessed the effect of waste dumpsites on groundwater quality of upper aquifers in Port Harcourt. Water samples were retrieved from hand-dug wells from a dumpsite and a control site and analyzed for physico-chemical parameters and heavy metal content. Results show that electrical conductivity of the dumpsite water samples was 42.06μS/cm while the control site water samples recorded 31.27μS/cm. Turbidity of the water samples ranged from 0.62NTU-0.65NTU. Total Dissolved Solids of the dumpsite water sample was 26.8mg/l while the TDS of the control site water sample was 33.70mg/l. The pH of water samples from both sites ranged from 5.46 -7.34. The pH of water samples from the dumpsite was slightly acidic (5.46). The average temperature of the water samples was approximately 28oC. Phosphate concentration of water samples ranged from 0.32 mg/l-0.54 mg/l while chloride levels ranged from 10.60mg/l-17.12 mg/l. All physico-chemical parameters and heavy metal content of the water samples all fell within the WHO and NSDWQ stipulated standards except for the lead concentration of the water sample retrieved from the dumpsite. The study also revealed that waste dumpsites did not alter the concentration of the measured physico-chemical properties and heavy metal concentration of water samples. However, the study recommended that periodic assessments of groundwater quality of waste dumpsites should be undertaken

15 Climate Change and the Evolving Fulani Pastoralists Cattle Production System in Nigeria: A Need to Retool Extension and Innovation Services

Abstract The Fulani pastoralists of Nigeria, as in other parts of West Africa, are traditionally semi- sedentary or nomadic herders, and are often described as the largest nomadic group in the world. The combined effects of climate change and instability due to terrorist activities have led to massive displacement of many Nigerian Fulani households to Southwestern Nigeria in search of refuge, pasture and water for their cattle. The objective of this project was to examine the current Fulani cattle production system. In addition to obtaining data via focus groups and direct observation, a survey was administered to members of 600 Fulani pastoralist households to determine cattle production techniques and herding strategies adopted. The observation period occurred over a 24 month period in three Southwestern Nigeria states (Ogun, Kwara and Oyo). Herding activities were mapped by using hand-held Global Positioning System (GPS) to obtain the coordinates of grazing routes and settlements. The results showed that the Fulani operate a system of male social contract and kinship networks in labor utilization and movement of herds. Among semi-sedentary and sedentary groups, the grazing orbit was usually within 5km to 10km radius of the settlement, depending on the season. Of the households observed, very few had access to tap or treated water (0.9% in Oyo, 1.4% in Ogun and 0.2% in Kwara). In Ogun, rivers and streams provided water for the largest number of households, while in Kwara, hand-dug wells were the largest providers. In Oyo, streams and rivers provided water for a large percentage of the Fulani households. In addition to a lack of basic water infrastructure, the results further revealed low productivity of cattle due to poor management and the utilization of cattle breeds with low genetic potential. It is recommended that micro-ranches, enhanced by extension services that provide training on cattle management, be implemented for this population.

Geochemical evolution and tracing of groundwater salinization using different ionic ratios, multivariate statistical and geochemical modeling approaches in a typical semi-arid basin

The vulnerability of semi-arid basin aquifers to long-term salinization due to the dissolution of groundwater chemical constituents is a major global problem. Despite this, resilient techniques of tracing the sources of groundwater salinization in semi-arid basin aquifers are still evolving due to the aquifer complexities. This study proves the effectiveness of the use of different ionic ratios, multivariate statistical, and geochemical modeling approaches to understand groundwater evolution and trace salinization in the semi-arid Pru Basin of Ghana. The basin is homogeneously composed of argillaceous sediments of the Oti/Pendjari Group of the Voltaian Supergroup. A total of 81 samples from hand-dug wells and boreholes within the Pru Formation of the Oti/Pendjari Group in the basin were collected for this study. Quantitative analysis of the data shows that the abundance of major ions follows the order: Na+ > Ca2+ > Mg2+ > K+ and Cl− > HCO3− > SO42−. The groundwater evolved from Na-HCO3, Na-HCO3-Cl, Na-Ca-HCO3 to Na-Mg-HCO3 water types in a decreasing order of abundance. Calculated meteoric genesis index (r2) indicates the dominance of deep meteoric water percolation effects on groundwater chemistry. Groundwater chemistry is principally controlled by water-rock interaction, ion exchange reactions, weathering (carbonate and silicate), salinization, and anthropogenic activities. Different ionic ratio plots and spatial distribution maps reveal the prevalence of salinization in the aquifer system, especially around the southwestern part of the basin. Revelle index assessment of the groundwater salinization level indicates that about 19.8% of the groundwater samples with RI values >0.5 is influenced by salinization. The groundwater salinization results from saline water intrusion from adjacent aquifers, mixing effects, ion exchange reactions, water-rock interaction, and anthropogenic activities. The geochemical modeling involving thermodynamic calculation of mineral saturation indices in PHREEQC indicates that groundwater is largely saturated with respect to majority of the carbonate and silicate mineral phases.

Occurrence of CTX-M, SHV and TEM β-lactamase genes in Extended Spectrum Beta-Lactamase (ESBL)- producing bacteria recovered from wastewater of a privately-owned hospital in Nigeria and a hand-dug well within its vicinity

BackgroundThe possibility of the dissemination of resistant bacteria and antimicrobials from healthcare facilities into shared environment is a threat to human health. This study investigated the occurrence of ESBL and AmpC β-lactamase genes in ESBL- producing bacteria isolated from wastewater of a privately-owned hospital in South-western Nigeria and underground water sources within its vicinity. MethodsHospital wastewater and water samples from borehole and hand-dug well, were collected over three months for the isolation of gram-negative bacteria. Phenotypic detection of ESBL production was done using the double disc synergy test (DDST), while characterization of positive isolates was done using API 20E identification kit. Susceptibility to antibiotics and detection of resistance genes were done using the disc diffusion method and Real-Time PCR respectively. Pulse field gel electrophoresis was used to determine the relationship between the isolates. ResultsSixteen ESBL- producing bacteria identified as Serratia fonticola (14), Enterobacter cloacae (1) and Pantoea agglomerans (1) were recovered. Resistance to ampicillin was 100%, ceftazidime (93.75%), amoxicillin-clavulanate (75.0%), trimethoprim-sulfamethoxazole (68.75%), gentamicin (50%), cefotaxime (43.75%), cefpodoxime (31.25%), ceftriaxone (18.75%) and 56.25% each to tetracycline and ciprofloxacin. No resistance was observed to cefoxitin. All the ESBL positive bacteria carried blaSHV, six carried blaSHV + blaTEM, while blaCTX-M-2, blaCTX-M-8 and blaCTX-M-25 were detected in three isolates. No isolate carried blaCTX-M-1, blaCTX-M-9, blaKPC, blaNDM-1, blaCMY-1 and ampC. All the ESBL- producing Serratia fonticola showed a high degree of genetic relatedness. ConclusionHospital wastewater and hand-dug wells in proximity to hospitals could be important reservoirs of ESBL- producing bacteria.

Hydrochemical characterization and quality assessment of groundwater in Meki River Basin, Ethiopian Rift

The present study was carried out in Meki River Basin (Ethiopian Rift) aiming at characterizing the hydrochemical composition of groundwater and evaluating the water quality status for drinking and irrigation uses. For this purpose, 63 primary groundwater samples from springs, hand-dug wells, and boreholes were collected and subjected to major ions analysis besides the in situ tests. The analysis result illustrates that Na+ and HCO3− are the principal cation and anion in the study area. The spatial investigation of the physiochemical parameters revealed that temperature, pH, TDS, EC, Na+, K+, HCO3−, Cl−, SO42−, and F− show a positive trend from the highland towards the rift floor along the groundwater flow direction. On the contrary, Ca2+ and Mg2+ show a negative tendency along the groundwater flow path. The groundwater of the study area generally evolves from predominantly fresh (TDS 750 mg/l) Na–HCO3 water type in the rift floor following the regional groundwater flow path. Gibbs diagram supported by ionic ratio (Na+ + K+/Ca2+ + Mg2+ vs total cations (TZ+) and Chloro-Alkaline Indices (CAIs) suggests that rock–water interaction (silicate hydrolysis and cation exchange) is the major hydrochemical processes controlling the evolution of the groundwater in the study area. 19% of TDS, 11% of EC, 83% of K+, 84% of HCO3−, and 52% of F− of the total water samples were unsuitable for the drinking uses compared with WHO water quality guideline. Spatial distribution maps of major ions (Ca2+, Mg2+, Na+, K+, Cl−, HCO3−, SO42−, and F−) and binary plots of physical parameters (temperature, pH, TDS, and EC) with elevation were produced. Both the spatial maps and binary plots generally show a water quality drop rift wards. Similarly, using multiple agriculture water quality criteria such as EC, SAR, RSC, PI, and Na%, the suitability of the groundwater for agricultural use was evaluated. Except a few samples in the rift floor, the majority of the water samples are found to be suitable for irrigation uses. As the study area is located where active geothermal activity and fluid circulation through fault systems, it is highly advised to carry out further toxic trace elements analysis to investigate the possible influence on the water quality.

Groundwater quality monitoring of a popular Niger Delta university town in Nigeria

This study provides a detailed scientific data on the quality of groundwater in Oleh. It aimed at helping to facilitate the planning of potable water supply scheme for the community. Water samples from boreholes (BHs) and hand-dug wells (HDWs) in the community were obtained for the determination of biological and physicochemical parameters, from December 10, 2016 to March 10, 2017 for dry season and May 01, 2017 to August 01, 2017 for wet season. Structured interviews were also organized for households for the estimation of degree of access to safe drinking water, quality perception and awareness of domestic treatment techniques. But for pH being lower in some locations, results arrived at reveal that the physicochemical parameters were within the World Health Organization (WHO) and Standard Organization of Nigeria (SON) limits. Cd and Pb in the BHs and HDWs were generally, slightly higher than the maximum limits of the WHO and SON. Though total coliform (TC) bacteria and Escherichia coli were found in the samples, HDWs had higher values. The small elevated values of Pb and Cd could be linked to crude oil exploration and processing activities in the sub-region. While most of the HDW samples (>72%) were found to be in the category of “low risk (FC, >11-100 cfu/100 mL), result of the survey showed that over <30% of households sourced their drinking water from hand-dug wells and had no working knowledge of domestic water treatment.

Study of Shallow Groundwater in Al-Diwaniya City / South Iraq

Al-Diwaniya city suffers from shallow groundwater levels, which cause serious problems on the foundation of builds in the area and affect the general health of citizens in residential areas. For investigating this problem, four different paths perpendicular to Shatt Al- Diwaniya were selected, along 11 hand-dug wells in the city to observe groundwater levels during a whole year (2019-2020). The work included observation boreholes water levels and comparing results with water levels in the Shatt al-Diwaniya. Along each of the four selected paths (A, B, C, and D), two boreholes are observed on each side of the Shatt al-Diwaniya. Depths of boreholes are from 6 to 12 m. All boreholes paths that represent shallow groundwater within residential districts. The water level of Shatt Al-Diwaniya and groundwater levels is monitored twice-per-month, especially over high and low water conditions within Shatt Al-Diwaniya. Hydrometric results showed a relationship between shallow groundwater and Shatt Al-Diwaniya levels in track A. The nature of this interaction along with the track A due to many local factors such as depth of water in Shatt Al-Diwaniya, amount of rainfall, factors of high water levels, conditions and climatic changes, soil factors and the current state of the deterioration of the sewage network in Diwaniya city. Finally, the results of the rest tracks indicated that the city is flooded with shallow groundwater due to the large sewage leakage in addition to the rainwater and that Shatt Al-Diwaniya does not affect groundwater in the area. Still, it works discharge groundwater in the city.

Physico-chemical and bacteriological evaluation of hand-dug wells in major markets in south-western Nigeria

Background: Quality of drinking water has always been a major health concern. Lack of access to safely managed water is responsible for high burden of waterborne diseases which disproportionately impact children and equity of women in Nigeria. This study, therefore, assessed the physico-chemical and bacteriological qualities of hand-dug wells in some major markets in Ibadan Southwestern, Nigeria. Methods: Twenty-two (22) water samples from hand-dug wells, measured sequentially along seven major marketswere tested for their physico-chemical and bacteriological characteristics. Following standard sampling procedures, in-situ measurements were taken for total dissolved solute (TDS), pH, electrical conductivity (EC), salinity and temperature. The most probable number – multiple tube technique was used for coliform enumeration in addition to total viable bacteria count (TVBC). Results: Mean pH (7.37±0.47), TDS (597.51±109.06mg/L), EC (748.79±110.67µS/cm), salinity (0.05±0.01mg/L), and temperature (28.75±0.58ºC) for all the marketswere withinWHO permissible limits except pH. High pH may be due to high organic matter content of the water samples. Bacteria genera comprising Esherichiacoli (37.5%), Staphylococcus aureus (25%), Proteus vulgaris (14.6%), Baccilusspp. (12.5%), Pseudomonas aeruginosa (8.3%) and Klebsiella spp. (2.1%).The mean TVBC of 500 to 192,000cfu/ml were higher than the stipulated WHO standard of &lt;1cfu/100ml.The presence of Esherichiacoli in hand-dug well water samples revealed human or animal faecal contamination.Conclusions: Water from these sources, intended for human consumption or washing of food items, maycompromise food safety and pose severe health risks to consumers. The provision of deep tube wells for safe drinking water, periodically testing of the water quality, and education of the users on improved hygiene practices will help in the provision of safe water to the public consumers.Keywords: Water quality, Hand-dug well, Bacteriological analysis, Coliforms,

Determination of hand-dug well conditions and groundwater quality in Ifo area of Ogun State, Nigeria

Background/Aim: Inadequate provision of public water for domestic uses has led to private house-owner to explore shallow water-well in Nigeria. While many of these wells are not constructed following standard procedure, the water quality is hardly determined in the laboratory. This research assessed the condition and water quality of hand-dug wells of a semi-urban area in Ogun State, Nigeria. Methods: Eleven sites were selected using stratified-random sampling method and a total of 110 wells were subjected to a standard checklist modified from swoveland. Ten water samples each from wells with high and low risk scores were collected in triplicates. Sixty samples in total were analysed for chemical parameters using flame photometer and UV/Visible Spectrophotometer while Total Bacteria and Coliform count were estimated using pour-plate technique.Results: The checklist evaluation of well characteristics showed that between 10 and 69 % of sampled wells were sited less than 2, 5 and 15 m from dwelling units, outdoor premises and sewer pipes/septic tanks respectively. It also revealed that well casing was present in about 62 % of the wells. Mean concentrations of Total Dissolved Solids (35.00±2.00 - 975.00±15.00 mg/L) and Total Hardness (3.20±0.45 - 399.05±383.41 mg/L) exceeded the permissible limits of WHO while K+ (50.24±30.11 - 0.05±0.05 mg/L), Na+ (2.87±0.14 - 152.56±12.51 mg/L), Cl- (28.80±0.00 - 244.80±7.20 mg/L), SO42- (1.00±1.00 - 1.33±0.58 mg/L) and NO3- (0.11±0.04 - 13.07±5.72 mg/L) were within the limits. The microbial load in the water samples ranged from 3.2x106 - 12.3x106 CFU/ml for bacteria count and 1.7x106 - 12.5x106 CFU/ml for coliform count.Conclusion: There were significant correlations between the well risk scores and water parameters. Well owner’s knowledge about standards for well constitute an intense factor in the determination of well-water quality. Therefore, the area of the wells should be protected in order to minimize contamination from sources of pollution.

An Assessment of Environmental Health Impacts of Toxic Chemical-Micronutrient Consumption in Groundwater from Dutse, Northwestern Nigeria

Background: Availability of water in the desired quantity and quality has been the key to human survival. This research assessed groundwater quality being consumed by the citizens of Dutse Area of Jigawa State, Northwestern Nigeria. Methods: Sixty groundwater samples (hand-dug wells and boreholes) from fifteen locations were analyzed for physical, chemical and biological parameters in order to determine their quality and potential health impact on the consumers/residents of this area. The parameters analyzed in the field were pH, Electrical Conductivity (EC) and temperature using standard methods. The sodium and potassium were analysed using flame photometer; sulphate, nitrate and phosphate using spectrophotometer; while calcium, magnesium, bicarbonate and chloride were analysed using titrimetric method. Analysis of metals in the groundwater samples was achieved through Inductively Coupled Plasma Mass Spectrometry at Activation Laboratory in Canada. Microbial load was analysed by serial dilution and counting. Results: The results showed that mean values of the physico-chemical parameters ranged as follows: pH, 5.00-7.00; temperature, 23.0-29.0 oC; EC, 190-2100 µs/cm; chloride, 34.55-690.90 mg/L; sulphate, 3.0-96.0 mg/L; bicarbonate, 20.0-60.0 mg/L; phosphate, 0.00-0.05 mg/L; nitrate, 0.05-0.47 mg/L; calcium, 18.1-462.4 mg/L; magnesium, 16.2-204.5 mg/L; sodium, 4.00-72.00 mg/L and potassium, 0.24-5.88 mg/L. The results of the heavy metal analysis shows the range of concentration of the following toxic metals: Aluminium, 20.0-853.0 µg/L; Cadmium, 0.05-0.23 µg/L; Lead, 0.87-22.8 µg/L; Mercury, 0.6-1.0 µg/L; Arsenic, 0.1-0.33 µg/L; Chromium, 0.2-0.3 µg/L; Berrylium, 0.5-1.2 µg/L and Cobalt, 0.09-0.71 µg/L. These were generally found to be within the WHO standard except in few cases. Similarly, the result of the microbial analysis shows the presence of Escherichia coli in almost all the groundwater samples. Conclusion: Cumulative effect of toxic metal in the consumed groundwater of the study area portends the risk of cancer and related diseases.

Quantifying Focused Groundwater Recharge Induced by Irrigation Surface Water Reservoirs in Crystalline Basement Areas for Complementary Irrigation

Through the practice of irrigation, surface water reservoirs (SWRs) contribute to the socio-economic development and food production activities of populations in Sub-Saharan Africa (SSA). However, they tend to dry up prematurely. One solution to circumvent these irrigation water shortages is to ensure their conjunctive use with groundwater. The objective of this study is to better understand the contribution of SWRs to groundwater recharge and to determine if groundwater may be considered as a complementary local resource for irrigation. The study was carried out on two watersheds in Burkina Faso, Kierma and Mogtedo. The spatiotemporal analysis of piezometric and SWRs level records coupled with physico-chemical analyses of water was used to characterize exchanges between SWRs and groundwater. The regional groundwater recharge at the scale of the watersheds was assessed. At the SWRs scale, a water balance methodology was developed and used to estimate focused recharge. The results show that SWRs interact almost continuously with groundwater and contribute focused recharge. The magnitude of this recharge is a function of the geological context and the sediment texture of the SWRs. It is estimated at 5 mm/day in Kierma and 4 mm/day in Mogtédo. These values are higher than the natural recharge estimated at 0.2 mm/day in Kierma and 0.1 mm/day in Mogtédo. Additionally, the values of hydraulic conductivity are between 0.01 and 2 m/day in Kierma and between 1 × 10−4 and 0.2 m/day in Mogtédo. These conductivities could allow pumping in large-diameter hand-dug wells with a significant yield between 0.5 and 120 m3/day in Kierma and between 0 and 10 m3/day in Mogtédo to palliate the early drying up of the SWRs.

Characterization of factors influencing water quality in Federal University of Agriculture Abeokuta and its Environ, Southwestern Nigeria

Quality of water is as important as its quantity, because it determines the state of health of man to a large extent. To maintain sustainable human development and public health of students’ community, water quality assessment was conducted by characterizing the influence of anthropogenic and natural processes on thirty-one (31) water samples from boreholes, hand-dug wells and surface water from Federal University of Agriculture Abeokuta and its environs. Physico-chemical data, statistical data, ionic-ratios, Gibb’s plot etc. were employed in delineating dissolved ions’ sources in the water from the study-area. Some physicochemical parameters were determined insitu with a potable multimeter, while the others were determined in the laboratory using standard methods. Various ionic plots showed that both carbonate dissolution and silicate weathering were the major contributors of ions in the water samples. Chloro-Alkaline Indices 1 and 2 values of samples collected were positive indicating direct ion exchange predominance. Factor analysis produced three factors accounting for 76% of the total variance. Factor-1 had high loadings (45.9%) on calcium, magnesium, bicarbonate, sulphate, potassium, pH, electrical conductivity and total dissolve solids suggesting water–rock interaction within the aquifer as the primary influence on groundwater quality and a common geogenic source. This was also corroborated by Gibb’s plot. Factors 2 and 3 revealed a moderate-high loading on NO3−, Cl− and pH suggesting that anthropogenic activities influence on water quality was quite significant especially in shallow and uncovered wells and surface water but minimal in borehole samples. Due to intense anthropogenic activities (farming and septic tank placement) and poor well management (open wells, poorly completed wells), groundwater drawn from shallower wells and surface-water appeared to be more polluted compared to those from boreholes. Generally, groundwater quality ranged from fairly to well suitable for drinking purpose except in shallow and poorly constructed hand-dug wells bordering farm areas.

ESTMAITION OF HEAVY METALS IN THE GROUNDWATER OF SELECTED AREAS FROM AL-DHALIA DISTRICT, AL-DHALIA GOV., YEMEN

In this research, the level of heavy metals Cadmium (Cd), Chromium (Cr), Copper (Cu), Iron (Fe), Manganese (Mn), Lead (Pb) and Zinc (Zn) in groundwater in selected areas in the region of Al-Dhalia district, Al-Dhalia Governorate, Yemen. Sixteen groundwater samples were collected from the study area included 9 artesian wells samples and 7 of hand-dug wells, and analyzed for the presence of heavy metals using Atomic Absorption Spectrophotometer (AAS). The results of the analysis showed that the concentrations of Pb, Mn and Cu in most of the studied samples have exceeded the Yemeni and WHO standards for drinking water, while the concentrations of Fe, Cd, Cr and Zn in most of the studied samples were low and fall within the optimum specifications for local and WHO drinking water.

Implications of Adopting Drip Irrigation System on Crop Yield and Gender-Sensitive Issues: The Case of Haramaya District, Ethiopia

Integration of advanced irrigation systems and technology is essential to improve crop water productivity and yields, especially in developing countries. This study aims at investigating the effects of adopting a drip irrigation system combined with hand-dug wells on crop water productivity and yields of household farmers and their perception on the proposed scheme over two cropping seasons in the Haramaya District, Ethiopia. We chose three locally called “Kebeles” within the District, and selected a certain number of household farmers that had similar characteristics within each Kebele. The selected farmers had practiced both the proposed drip irrigation with private hand-dug wells water supply (intervention pilots) and traditionally-used surface irrigation with communal water supply (non-intervention pilots) schemes. We also conducted interviews with the selected household farmers, personal observations, and measurements on crop water productivity and yields for both intervention and non-intervention pilots. We found that the proposed drip irrigation system significantly improved the crop productivity and yields of the farmers. More importantly, findings indicated that the use of drip irrigation system combined with hand-dug well water supplies reduced the over-exploitation of water (water savings) and labor-intensive manual-irrigation. The latter particularly helped women to work less on their farm works and thus provided them a flexible system to expand their plot sizes and grow a variety of crops. Overall, the drip irrigation system with water supply from hand-dug wells is highly recommended as it allows a flexible system for household farmers and provides an opportunity to expand their plot sizes with a variety of crops, which is also expected to mitigate the negative implications of climate change on freshwater water resources and crop productivity. However, the farmers of the Haramaya District expressed their need on capacity building, financial and technical supports from local to regional governments and other agencies to ensure an efficient and cost-effective drip irrigation system and to further improve their crop water productivity and yield, food self-sufficieny, and livelihoods. It is also important to consider market-based farming approaches, while promoting efficient irrigation systems and self-supply to ensure quick investment returns. This study recommends to adopt and expand the proposed drip irrigation system at household levels in Sub-Saharan and other similar regions.

Evolution of groundwater hydrogeochemistry and assessment of groundwater quality in the Anayari catchment

The quality of groundwater in the Lower Anayari Catchment was assessed for its suitability for drinking, domestic and irrigation purposes. The Lower Anayari Catchment lies in a semi-arid region in Ghana and covers an area of about 253 km2. The area is predominantly an agricultural area and groundwater is the main source of water for domestic and agricultural purposes. Sixty-six groundwater samples were collected from boreholes and hand-dug wells. The samples were analysed for their physico-chemical properties. Calcium (Ca2+) and bicarbonate (HCO3−) were the most abundant cation and anion respectively. The major water types in the study area are of Ca–Mg–HCO3 and the mixed Ca–Mg–Cl type. The water chemistry is mainly controlled by reverse ion exchange, dissolution of minerals and evaporation. The quality of groundwater for drinking and domestic use was assessed using the weighted arithmetic water quality index (WQI) approach and the values showed that 94% of the samples were of ‘good’ quality while 6% were of poor quality. The groundwater was generally good for drinking except for some few samples which showed elevated F and NO3− concentrations above the WHO guideline values of 1.5 mg/L and 50 mg/L respectively. The quality of groundwater for irrigation was also assessed and the EC, %Na, SAR and RSC ranged between 240 and 710 μS/cm, 23.54–38.93, 0.47–1.04 and −1.9 to −0.09 respectively. The groundwater in the area has low sodicity with medium salinization and can generally be used for irrigation without prior treatment. Groundwater quality in the Anayari catchment is influenced by geology with little anthropogenic influence. Hence, proper groundwater management strategies and policies are needed to protect the aquifers.

Human Health Risk Assessment of Some Toxic Metals in Groundwater Resources in Four Selected Towns of Delta State, Nigeria

Aims: The health risk assessment of some toxic metals in groundwater in four selected towns of Delta State, Nigeria was confirmed by this study.&#x0D; Methodology: Ninety six groundwater samples were obtained from sixty four hand-dug wells and thirty two boreholes between December 2016 and May 2017. Samples were analyzed for heavy metals using standard procedures. Data collected was subjected to descriptive and inferential statistics using the Statistical Package for Social Sciences (SPSS) for Windows version 22.0. Health Risk Assessment for Non cancer hazard and carcinogenic effects were determined.&#x0D; Results: The HQ of Cr, Mn and Ni were below 1.0 indicating no threat to the water consumers while the HQ values for Pb, Cd and Cu were above 1.0 indicating risk to human health. The HI value was found to be greater than 1.0, indicating noncarcinogenic adverse effects. The estimated Lifetime of Carcinogenic Risks (LTCR) for Pb, Cr, Cd and Ni exceeded the predicted lifetime risk for carcinogens of 10−6 from ingestion pathway. The groundwater had higher risks of Cr and Cd as LTCR value in most sites were &gt;10−4. The high LTCR should be given high priority as public health is concerned.&#x0D; Conclusions: This study indicated possible non-carcinogenic and carcinogenic human health hazard from groundwater consumption in study area through oral consumption.

Comparative Study of Water Quality From Boreholes and Hand-Dug Wells: Case of Namatapa in Bangwe Township

Comparative Study of Water Quality From Boreholes and Hand-Dug Wells: Case of Namatapa in Bangwe Township

ON THE USE OF KRIGING MODEL CONCEPT TO DETECT GROUNDWATER POTENTIAL ZONES IN HILLY DUTSIN-MA, NORTHWESTERN NIGERIA

In this present study, the geology, relief, spatial variation and challenges of groundwater quality has been carried out, using Kriging Model. The methodology employed was drawn from primary and secondary data sources. Detailed chemical analyses for some of the parameters of the groundwater were done on a total of twenty-one (21) samples of both hand-dug wells and borehole waters collected during the full field investigation. In the laboratory analysis, the AAS and XRF machines were used to analyze eight (8) samples, namely: Temperature, pH, Total Dissolved Solids (TDS), EC, Total Hardness, Lead, Iron, and manganese. The results of the chemical analyses which were akin to groundwater geochemical characterization based on the ranges of parameters shows that the value of pH in the study area ranges from (6.53 to 7.30), The Total Dissolved Solids ranges between (0.00 to 24.00), the EC has concentrations between (0.06 to 22.00) which was also around the permissible units of both SON and WHO. Total Hardness of the samples of the area run from lowest concentrations of (60 to 3915) which does not exceed the SON permissible unit, but exceed the recommended limit of WHO. The corresponding limited ranges of iron and manganese ranges from (0.53 to 15.24 and 0.4 to 3.35),the concentrations of Lead from lowest to highest were (0.74 to 2.31), both of which defy the recommended limits of WHO (0.05) and that of SON (0.01). Based on this, it was concluded that some of the groundwater sources assessed are safe for human consumption. If the practice of consuming groundwater without treatment continues, it may lead to health hazard.. ANOVA-F (One Way) was adopted in testing the hypothesis (Calculated F=6.63 while Critical F=2.16). The study recommended that appropriate measures should be taken to bring the higher concentrated parameters to desired levels.

Geophysical and hydrophysical evaluation of groundwater around the Igbenre Ekotedo dumpsite Ota, Southwest Nigeria, using correlation and regression analysis

A study involving geophysical survey and groundwater analysis was carried out at the Igbenre Ekotedo dumpsite in Ota, Southwest Nigeria. The aim was to monitor and track the depth of leachate contamination around the dumpsite. A proposed simple multiple linear regression (MLR) model of groundwater total dissolved solids (TDS) was also developed. This was achieved by correlating the observed TDS of groundwater samples collected within and around the vicinity of the dumpsites with multiple terrain conductivity data derived from a geophysical method. The results of the electrical resistivity tomography (ERT) obtained along four profile lines in August 2014, and a time-lapse survey in December 2015 delineated leachate plumes as low-resistivity zones ranging between 0.54 and 12.5 Ω m around the dumpsite, with good correlation between the wet and dry season models. The results also showed that leachate from the decomposed refuse materials has polluted the subsurface under the dumpsite from the surface to a depth of about 45 m, and by extension contaminating groundwater aquifer around the area. Results from the electromagnetic (EM-34) experiment and groundwater TDS parameters from seven (7) boreholes around the vicinity of the EM profiles showed a strong positive correlation. Therefore, a simple multiple linear regression (MLR) TDS model that relates the TDS data obtained from boreholes to the geophysical parameters obtained from the EM-34 data (HD 20, HD 40, and VD 40) was developed for the purpose of efficient groundwater resources monitoring and management around the dumpsite and their communities. The predictive power of the developed MLR TDS model was also apprised to determine the feasibility of using the TDS model to predict and estimate groundwater TDS around the study area. The developed TDS model can be reliably deployed for groundwater TDS estimation and monitoring around the study area where there are no boreholes, but with only terrain conductivity data. However, where there are borehole and hand-dug wells, terrain conductivity data around the area alone can be applied to the model to determine TDS concentration in groundwater, thus reducing the time and cost of determining and monitoring both parameters independently.

Implications of carbonates and chlorides contamination in groundwater: Examples from textile tie and dye markets in some parts of Southwestern Nigeria

Objectives: To evaluate the impact of common mineral dyes in effluents from dyeing processes on the quality of groundwater at Itoku and Asero, Abeokuta in Nigeria. Methods: Thirty-two (32) samples were examined by determining the In-situ parameters: Total Dissolved Solids (TDS), Electrical Conductivity (Ec) and pH with the aid of a multi-parameter portable meter(model Testr-35); Chemical parameters were determined with Atomic Absorption Spectrometry (AAS)and Titration methods for both cations and anions. Collected samples were analyzed for heterotrophic bacteria load using standard method. Findings: Elevated Ec-1830 µS/cm and TDS-1020mg/l values at Odutola-8 exceeded the WHO permissible limit with bicarbonate, carbonate and chlorides presence, in the water sample. DO at Ifote-6.0, Asero-6.8, Ifote-7.1, Asero carwash-7.9 was greater than WHO standard, specifying water that can support aquatic life and micro-organisms. However, other areas had low dissolved oxygen below the specified permissible limit. The results of the physicochemical parameters including; Chloride and Carbonate levels in effluent and groundwater in most of the studied sites were higher than the World Health Organization (WHO) permissible limits. Dye effluents and well water samples displayed high microbial loads. Predominant bacteria isolated from the effluent and groundwater included Aspergillus spp. Pseudomonas aeruginosa and Bacillus subtilis. Polycyclic aromatic hydrocarbon (PAHs) observed indicated probable human carcinogens found where dye fabrication processes were high and effective. Novelty: Dye effluents have high bacterial and fungal loads. Similarity in the predominant bacteria isolated from effluent and groundwater from the hand-dug wells indicated that the effluent from the dyeing processes is negatively impacting the groundwater and this may pose a risk to public health. High levels of Carbonates, bicarbonates and chlorides in groundwater indicate contamination; making the water unfit for human and animal consumption. Keywords: Minerals; dyes; contamination; groundwater; carbonates; chlorides