Hydrogeochemical Characterization and Water Quality Assessment of Surface Water Resources in Obomkpa, Western Niger Delta, Nigeria

doi:10.21203/rs.3.rs-4863954/v1

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Hydrogeochemical Characterization and Water Quality Assessment of Surface Water Resources in Obomkpa, Western Niger Delta, Nigeria

https://doi.org/10.21203/rs.3.rs-4863954/v1

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The hydrogeochemical analysis of surface water resources in Obomkpa and its surrounding areas aimed to characterize their physical, chemical, and microbial properties. This study provides crucial information on the quality and suitability of the water for various uses, focusing on acidity, mineral content, and suitability for irrigation and domestic purposes. Six water samples were collected from rivers in the study area and analyzed using standard methods. The parameters assessed included pH, total dissolved solids (TDS), total hardness, electrical conductivity (EC), dissolved oxygen (DO), biochemical oxygen demand (BOD), total suspended solids (TSS), turbidity, salinity, and concentrations of various ions, heavy metals, and microbial properties. The chemical analysis revealed that the water resources are generally acidic, with an average pH of 5.89. They are fresh (TDS mean of 28.62 mg/l) and soft (total hardness mean of 16.83 mg/l), but the acidity renders them unsuitable for industrial purposes. Other parameters such as EC (mean 46.82 µs/cm), DO (mean 4.98 mg/l), BOD (mean 1.21 mg/l), TSS (mean 5.17 mg/l), turbidity (mean 4.1 NTU), and salinity (mean 14.88 mg/l) were within acceptable ranges for various uses. Anion analysis (sulphate, nitrate, bicarbonate, chloride) and cation analysis (calcium, magnesium, sodium, potassium) showed varying concentrations, with sulphate (mean 5.11 mg/l), bicarbonate (mean 27.74 mg/l), and chloride (mean 8.27 mg/l) being notable. Heavy metal analysis revealed concentrations of iron, copper, and zinc (means of 0.016 mg/l, 0.011 mg/l, and 0.204 mg/l respectively), with zinc exceeding acceptable limits. Correlation analysis showed relationships among physiochemical parameters, with correlation coefficients ranging from − 0.24 to 0.99. Similar correlations among heavy metals, cations, and anions were observed (correlation coefficient (r²) range of -0.21 to 0.70 and 0.12 to 0.98 respectively). The study concludes that while surface water resources in Obomkpa are generally suitable for domestic and irrigation purposes, they require treatment to reduce acidity and control zinc levels. The water chemistry analysis identified the dominant water types as Ca-Mg-(Na)-Cl and Ca-Mg-(Na)-SO₄, indicative of hard water with high calcium and magnesium content. This study contributes novel insights into the hydrogeochemical characteristics of Obomkpa's water resources, emphasizing the need for targeted remediation to enhance water quality for various applications.

Hydrogeochemical Analysis

Water Quality

Water Acidity

Heavy Metals and Water Treatment

Water quality is an important concern in industry, agriculture, and public health. Making sure people have access to clean water has always been a challenge. Water pollution is one of the most pressing environmental issues of our time, and it is exacerbated by the disposal of industrial waste into bodies of water (Sogbanmu et al., 2019; Egbueri et al., 2020; Oyelakin et al., 2020; Egbueri et al., 2021). Large quantities of water may not always translate to potable water. Water that contains tastes, odour, colours, or other objectionable substances is inappropriate for use in homes, companies, or agriculture (Ighalo & Adeniyi, 2020). To assess the quality of surface water, its geochemical composition must be evaluated. Geology has a significant influence on the chemistry of surface and groundwater, particularly the types of rocks and the products they weather (Ganiyu et al., 2018; Onyeanuna et al., 2019; Eyankware et al., 2021; Onwe et al., 2021). Akintola et al. (2018) and Anyanwu et al. (2021) both explore how anthropogenic activities alter the composition of surface water bodies, as well as how biomass interacts with the environment in wooded regions.

Water pollution can come from a variety of sources, such as sewage effluent, industrial discharges, urban stormwater, and agricultural runoff. These pollutants contribute several contaminants into water systems, including pathogens, heavy metals, nutrients, and organic substances (Ighalo et al., 2021; Titilawo et al., 2018). Overuse of fertilizers in agriculture leads to the outflow of nutrients, primarily phosphorus and nitrogen, which can eutrophicate aquatic habitats. Algal blooms deplete oxygen in the water, making it unfit for human consumption and recreational usage, causing harm to aquatic life (Hussain, 2018; Streicher et al., 2021). Heavy metals such as lead, cadmium, and mercury are discharged into bodies of water by industrial processes, contributing significantly to water pollution. These metals offer major health risks to both humans and wildlife since they are toxic even at low doses and can accumulate in the food chain. Urbanization introduces pollutants from road surfaces, construction sites, and heavy metals into stormwater systems, ultimately harming rivers, lakes, and seas (Chris, 2018).

Bacteria, organic debris, and pharmaceuticals introduced by sewage and wastewater discharges contaminate aquatic bodies. Improperly handled sewage can transmit waterborne infections such as cholera, dysentery, and hepatitis (Aniyikaiye et al., 2019; Chigor et al., 2020). Pharmaceutical residues in water have the potential to influence aquatic organisms' reproductive and endocrine systems. Water quality is ensured by a variety of processes, including monitoring, regulation, and treatment (Ogunbanwo et al., 2020). Monitoring the geochemical characteristics of surface water can assist establish the extent and source of pollution. It accomplishes this by measuring pH, electrical conductivity, dissolved oxygen, main ions (calcium, magnesium, sodium, and potassium), and trace elements (lead, arsenic, and cadmium). Contaminants at trace levels can be detected and evaluated using advanced analytical procedures such as spectrometry and chromatography (Adesakin et al., 2020).

For a variety of applications, treatment methods are critical for eliminating impurities and ensuring water safety. Conventional water treatment techniques such as coagulation, flocculation, sedimentation, filtration, and disinfection are successful at eliminating pathogens, suspended particles, and some dissolved contaminants (Udeagbara et al., 2021). To address growing contaminants such as medicines, personal care products, and microplastics, innovative treatment technologies such as membrane filtration, activated carbon adsorption, and sophisticated oxidation processes are gaining favour (Wang et al., 2020). Water quality must be maintained using sustainable water management strategies. Integrated water resources management, or IWRM, advocates the integrated development and management of water, land, and other resources to maximize social and economic well-being while preserving ecological sustainability (Al-Jawad et al., 2019; Ngene et al., 2019). Sustainable water quality management solutions include reducing pollutant loads at the source, encouraging wastewater reuse and recycling, and safeguarding natural water bodies through conservation and restoration programmes (Ngene et al., 2021).

This study will look at the hydrogeochemical properties of surface water resources in Obomkpa and the surrounding area to determine whether they are appropriate for municipal usage. Because surface water is used by approximately 80% of the labour force in the area for agricultural purposes, it is critical to assess water quality in the presence of potential human contaminants. This work contributes to the body of knowledge by providing a complete hydrogeochemical investigation of Obomkpa's surface water. Its goal is to advise targeted remediation actions that improve water quality for a variety of uses.

Obomkpa is situated in the Aniocha North local government area of Delta State, Nigeria, at an altitude of around 197 metres above sea level. The settlement is located at a latitude of 6°24'46.08" North and a longitude of 6°29'28.93" East as shown in Fig. 1. Obomkpa experiences a tropical climate, which is influenced by the presence of two distinct air masses. One of the air masses that affects Nigeria is a warm and humid tropical marine air mass originating from the Atlantic Ocean. This air mass brings winds from the southwest direction.

The climate in Obomkpa features distinct wet and dry seasons. The wet season begins around the middle of March and continues until July, characterized by heavy rains and high humidity. This is followed by a short dry season, often referred to as the "August break," which lasts for about a month from July to August. The wet season resumes after the August break, extending from September to October. The dry season spans from November to mid-March. The average annual temperature in Obomkpa is around 26.5°C, with an average annual rainfall of 1717 mm.

The topography of Obomkpa is derived from the general topographic map of the area. The terrain elevation increases progressively from the North-Western part of the map, starting at about 200 meters, and rises towards the South-Eastern part, reaching elevations of about 600 meters. Further elevation increases to about 700 meters are observed as one moves towards Ukwu-Nzu. This topography is marked by the presence of several rivers, including the Nnemagadi, Iyiocha, and Iyipukpa, creating an irregular pattern of low, steep terrain.

Obomkpa is drained by a network of seasonal rivers, which include River Iyi-Ilo, River Iyi-Odo, River Iyi-Kpukpa, River Iyiocha, and River Nnemagadi. The surrounding areas are also drained by rivers such as the river Iyi-Enugu, Idumuje River, and Igbodo River as shown in Fig. 1. These rivers typically flow in a northwest-southeast direction from their sources and are structurally controlled, with all tributaries ultimately connecting to the river Niger. The study region is located in the Niger Delta, a well-known Cenozoic sedimentary basin. It is situated on the Equatorial West Coast of Central Africa, on the continental edge of the Gulf of Guinea. The area is made up of four primary geological formations, each with its own unique contribution to the hydrogeology and beauty (Chima et al., 2019).

The Imo Shale Formation serves as the foundation layer and earliest strata. The formation is composed of thin sandstone layers, particularly towards the top, and finely grained, dark grey to bluish-grey shales that are intermittently laced with clay ironstone (Ikegwuonu et al., 2020). The Ameki Formation sits atop the Imo Shale and spans the Eocene to Oligocene epochs (Ogbe & Osokpor, 2021). In general, this formation is made up of white sandstone with medium to coarse grains; nevertheless, there are some variations, such as grey-green sandstone, bluish calcareous silt, mottled clays, and rare thin layers of limestone. The lithology of the Ameki Formation varies greatly laterally, with fine- to coarse-grained sandstone lenses mixed with calcareous shales and shelly limestone in the bottom level (Ahukaemere et al., 2020).

The Ogwashi-Asaba Formation follows, and it is famous for its widespread distribution across approximately 4,900 km2 in the Niger Delta region. This stratum is made up of carbonaceous shale, clay, and coarse-grained sandstone, with continental lignite seams interspersed throughout (Ogala et al., 2020). These lignite seams, which range in thickness from millimetres to six metres, are typically fissile, thinly laminated, and brownish to black in hue, with fragments of wood and leaves mixed throughout. They are particularly visible in river valleys such as Iyi-Ocha, Nkpunkpa, Iyiodo Springs, and the Nnem-Agadi River in Obomkpa (Boboye & Chidiebere, 2023).

The Benin Formation, the youngest formation in the sequence, caps the geological column. It is a continuation of sedimentary deposition, contributing to the region's overall stratigraphy and bearing unique characteristics that are not fully described in this description (Ogbe & Osokpor, 2021). Significant differences in thickness and composition can be seen throughout these layers, indicating the complex sedimentary processes and geological history that have sculpted the Niger Delta region over millions of years. Thin, discontinuous clay streaks and lenses within thick sandy stages provide additional insight into the stratigraphic complexity and interaction of depositional events that have produced the basin's current geological structure (Olayiwola, 2021; Okeke et al., 2021).

The Ogwashi-Asaba Formation's lignite layers show the region's potential for energy sources, but further research is needed to assess their economic viability and environmental impact. These layers present several research opportunities for future development and resource management techniques (Ogala et al., 2020). They are commonly found in drill holes, streams, riverbanks, and road cut-outs.

3.1 Sampling and Analysis

A total of six water samples were collected from five major rivers at six distinct points. Three sampling points were located in two rivers within Obomkpa, while the other three points were situated in three rivers surrounding the Obomkpa community in the Aniocha North local government area of Delta State. Each sample was immediately labeled upon collection. To avoid contamination, the bottles were thoroughly rinsed with stream water before sampling. Samples were taken from mid-stream to ensure they were representative of the flowing water. The collected samples were then analyzed for various physicochemical and biological parameters using standard procedures. Heavy metal concentrations, specifically lead (Pb), cadmium (Cd), iron (Fe), copper (Cu), zinc (Zn), and nickel (Ni), were measured with an Atomic Absorption Spectrophotometer (AAS). Additional physicochemical parameters were assessed using other established standard methods.

4.1 Assessment of Water Quality Parameters in Surface Water Samples

Key parameters measured include pH, temperature, total dissolved solids, conductivity, dissolved oxygen, biochemical oxygen demand, total suspended solids, turbidity, salinity, alkalinity, chemical oxygen demand, and total coliform count. The results are compared with WHO (2006) and NIS (2007) standards to evaluate the water quality in these areas, as shown in Table 1.

Table 1

Water quality parameters of surface water for the study area
Parameters	Nnemagadi	Iyiocha Ups	Iyiocha Ds	Idumuje	Iyi Enugu	Ogiakpa	WHO (2006)	NIS (2007)
pH	6.70	5.72	5.97	5.86	5.58	5.80	6.5–8.5	6.5–8.5
Temperature (°C)	27.90	29.60	30.10	28.10	29.50	28.90	> 40	Ambient
Total Dissolved Solids (mg/l)	60.60	25.50	18.20	30.90	20.70	15.80	500.00	500.00
Conductivity (µS/cm)	96.10	41.20	29.70	52.01	34.03	27.90	100.00	1000.00
Dissolved Oxygen (mg/l)	4.60	5.30	4.20	4.10	6.20	5.50
Biochemical Oxygen Demand (mg/l)	1.20	0.97	1.10	1.50	1.30	1.20
Total Suspended Solids (mg/l)	20.00	3.00	1.00	1.00	5.00	1.00	-
Turbidity (Nephelometric Turbidity Units)	18.85	1.92	0.40	0.07	3.41	0.73	5.00	5.00
Salinity (mg/l)	22.66	21.10	11.81	15.18	10.12	8.43
Alkalinity (mg/l, as CaCO₃)	93.35	34.30	42.00	38.80	30.32	38.80
Chemical Oxygen Demand (mg/l)	2.54	2.33	2.74	3.42	2.08	1.76
Total Coliform Count (MPN/100ml)	< 2.0	< 2.0	< 2.0	< 2.0	< 2.0	< 2.0	0.00	0.00

The pH values of the sampled locations ranged from 5.58 to 6.70, with the highest value recorded at Nnemagadi and the lowest at Iyi Enugu. The pH values for Iyiocha Ups (5.72), Iyiocha Ds (5.97), Idumuje (5.86), and Ogiakpa (5.80) were slightly acidic. According to the WHO and NIS standards, the acceptable pH range for drinking water is 6.5 to 8.5. Except for Nnemagadi, all other sites recorded pH values below the recommended range, indicating slightly acidic conditions that could affect the palatability and corrosion potential of the water. Water temperature ranged from 27.90°C to 30.10°C, with Iyiocha Ds recording the highest temperature and Nnemagadi the lowest. The WHO guideline suggests a maximum temperature of 40°C, and while all samples were well within this limit, variations in temperature can influence the solubility of gases and the rate of chemical reactions in the water. The relatively higher temperatures observed at Iyiocha Ups (29.60°C) and Iyi Enugu (29.50°C) could potentially enhance microbial activity.

TDS concentrations varied significantly, ranging from 15.80 mg/l at Ogiakpa to 60.60 mg/l at Nnemagadi. All samples were well below the WHO and NIS guideline value of 500 mg/l, indicating that the water samples had low concentrations of dissolved minerals and salts. Low TDS levels generally indicate good water quality with minimal salinity issues. However, extremely low TDS can also result in water that is flat or tasteless. Conductivity values ranged from 27.90 µS/cm at Ogiakpa to 96.10 µS/cm at Nnemagadi. The values for all samples were below the WHO and NIS standards of 100 µS/cm and 1000 µS/cm, respectively. Conductivity is a measure of the water's ability to conduct electricity, which correlates with the concentration of ions in the water. Lower conductivity indicates lower ion concentration, which is typical of freshwater systems.

DO levels ranged from 4.10 mg/l at Idumuje to 6.20 mg/l at Iyi Enugu. Adequate DO levels are crucial for the survival of aquatic organisms. Although there is no specific WHO guideline for DO, levels above 5 mg/l are generally considered good for most aquatic life. Iyi Enugu and Ogiakpa had DO levels above this threshold, indicating good aeration and potentially healthy aquatic ecosystems. The lower DO levels at Nnemagadi (4.60 mg/l), Iyiocha Ds (4.20 mg/l), and Idumuje (4.10 mg/l) might indicate limited oxygen availability, possibly due to higher temperatures or organic matter decomposition. BOD values varied from 0.97 mg/l at Iyiocha Ups to 1.50 mg/l at Idumuje. BOD measures the amount of oxygen required by microorganisms to decompose organic matter in water. Lower BOD values indicate lower levels of organic pollution, which is consistent with the values observed across the samples. These values suggest that the water bodies are relatively clean and have low levels of biodegradable organic matter.

TSS concentrations ranged from 1.00 mg/l at Iyiocha Ds, Idumuje, and Ogiakpa to 20.00 mg/l at Nnemagadi. TSS indicates the number of solid particles suspended in water, which can affect water clarity and quality. Except for Nnemagadi, all other sites had very low TSS values, indicating clear water with minimal particulate matter. The higher TSS at Nnemagadi could result from runoff, erosion, or other sources of particulate pollution.

Turbidity levels ranged from 0.07 NTU at Idumuje to 18.85 NTU at Nnemagadi. The WHO and NIS guidelines recommend a turbidity level of 5 NTU. While most sites met this standard, Nnemagadi (18.85 NTU) and Iyi Enugu (3.41 NTU) showed higher turbidity, which could indicate the presence of suspended particles, pathogens, or other pollutants. High turbidity can reduce light penetration, affecting aquatic plant growth and potentially harboring harmful microorganisms. Salinity levels ranged from 8.43 mg/l at Ogiakpa to 22.66 mg/l at Nnemagadi. Salinity measures the concentration of dissolved salts in water. While there are no specific WHO or NIS standards for salinity, the observed levels indicate that the water is fresh, with low salinity levels typical of inland water bodies. Alkalinity values varied from 30.32 mg/l at Iyi Enugu to 93.35 mg/l at Nnemagadi. Alkalinity measures the water's capacity to neutralize acids, which is important for maintaining pH stability. Although there are no specific WHO or NIS standards for alkalinity, the observed levels indicate that the water has sufficient buffering capacity to resist pH changes.

COD values ranged from 1.76 mg/l at Ogiakpa to 3.42 mg/l at Idumuje. COD measures the total amount of oxygen required to oxidize both organic and inorganic substances in water. Lower COD values generally indicate better water quality with lower levels of pollutants. The observed COD values suggest that the water bodies have low levels of organic and inorganic contaminants. TCC values for all samples were below 2.0 MPN/100ml, meeting the WHO and NIS guideline of zero coliforms per 100ml. This indicates that the water samples were free from fecal contamination and safe from pathogens that could cause waterborne diseases. Maintaining low TCC is crucial for public health, particularly in drinking water sources.

Most of the water samples were slightly acidic, falling below the acceptable range set by WHO and NIS. This slight acidity could be due to natural factors such as soil composition and organic matter decomposition or anthropogenic influences like acid rain and industrial discharges (Laniyan & Morakinyo, 2021). All sampled locations recorded temperatures well within the acceptable range, with slight variations. These temperatures are typical for tropical regions and suggest no significant thermal pollution (Sule et al., 2020). Both TDS and conductivity values were well below the guidelines, indicating low mineral and ion content in the water. This suggests that the water sources are relatively unpolluted by salts and other dissolved substances (Aladejana et al., 2020; Ogwueleka & Christopher, 2020). The observed DO levels were generally adequate for supporting aquatic life, with only slight variations among the sites. The low BOD values further indicate good water quality with minimal organic pollution (Ovonramwen, 2020; Alum et al., 2021). While most sites had low TSS and turbidity, NNEMAGADI showed higher levels, possibly indicating localized pollution or runoff. These parameters are important for assessing the aesthetic and biological quality of water. The low salinity and COD values suggest minimal pollution from salts and organic/inorganic substances (Ajani et al., 2021). The alkalinity levels indicate good buffering capacity, important for maintaining pH stability (Ali et al., 2021). The absence of coliform bacteria in all samples indicates that the water sources are free from fecal contamination, making them safe for consumption and recreational use (Chigor et al., 2020).

4.2 Evaluation of Anion Concentrations in Surface Water Samples

Table 2 presents the concentrations of these anions and their compliance with the recommended guidelines. These results are compared against WHO (2006) and NIS (2007) standards to assess water quality.

Table 2

Concentrations of anions in surface water compared with WHO (2006) and NIS (2007) standards
Parameters	Nnemagadi	Iyiocha Ups	Iyiocha Ds	Idumuje	Iyi Enugu	Ogiakpa	WHO (2006)	NIS (2007)
Sulfate (SO₄²⁻) (mg/l)	8.27	5.69	3.60	6.90	4.83	1.38	400.00	100.00
Phosphate (PO₄³⁻) (mg/l)	0.24	0.20	< 0.001	0.21	< 0.001	< 0.001	10.00
Nitrate (NO₃⁻) (mg/l)	0.15	0.11	0.07	0.09	0.13	0.05	50.00	50.00
Bicarbonate (HCO₃⁻) (mg/l)	55.98	20.57	25.18	23.26	18.18	23.26	500.00	500.00
Chloride (Cl⁻) (mg/l)	12.58	11.72	6.56	8.43	5.62	4.68	200.00	250.00

The concentration of sulfate in the surface water samples ranged from 1.38 mg/l in Ogiakpa to 8.27 mg/l in Nnemagadi. All locations exhibited sulfate levels significantly below the WHO guideline of 400 mg/l and the NIS standard of 100 mg/l. Sulfate is a naturally occurring substance in water bodies, primarily from the dissolution of mineral rocks. The low levels of sulfate in these locations indicate minimal industrial or agricultural runoff, which can contribute to higher sulfate concentrations.

Phosphate levels in the water samples were very low, with values ranging from less than 0.001 mg/l in Iyiocha Ds, Iyi Enugu, and Ogiakpa to 0.24 mg/l in Nnemagadi. These values are well below the WHO recommended limit of 10 mg/l. Phosphates can enter water bodies from agricultural runoff, wastewater discharge, and detergents. The low phosphate concentrations suggest that these sources are not significantly impacting the water quality in these areas. Nitrate concentrations in the water samples varied from 0.05 mg/l in Ogiakpa to 0.15 mg/l in Nnemagadi. These values are well below the WHO and NIS limits of 50 mg/l. High levels of nitrates can be harmful, particularly to infants, as they can cause methemoglobinemia or "blue baby syndrome." The low nitrate levels across all locations indicate limited agricultural runoff and low levels of nitrogenous waste, which are common sources of nitrate pollution.

Bicarbonate levels ranged from 18.18 mg/l in Iyi Enugu to 55.98 mg/l in Nnemagadi. The WHO and NIS standards set a maximum limit of 500 mg/l for bicarbonate. Bicarbonates are crucial in maintaining the pH balance in water. The bicarbonate concentrations in all the sampled locations are significantly below the guideline values, indicating a stable pH environment without significant acidification or alkalization processes. Chloride concentrations in the water samples ranged from 4.68 mg/l in Ogiakpa to 12.58 mg/l in Nnemagadi. These values are well below the WHO guideline of 200 mg/l and the NIS standard of 250 mg/l. Chlorides can enter water bodies from natural sources, agricultural runoff, and effluents from sewage and industrial processes. The low chloride levels in these locations suggest minimal pollution from these sources.

The results of this study reveal that the concentrations of sulfate, phosphate, nitrate, bicarbonate, and chloride in surface water samples from Nnemagadi, Iyiocha Ups, Iyiocha Ds, Idumuje, Iyi Enugu, and Ogiakpa are all within the permissible limits set by WHO and NIS standards. This indicates that the surface water quality in these areas is generally good and safe for consumption and other uses. The low levels of these anions suggest minimal anthropogenic impact, such as agricultural runoff, industrial discharge, or domestic wastewater (Egbueri et al., 2020). It is important to maintain and regularly monitor these parameters to ensure the continued safety and quality of the water. Further, the variation in the concentrations of these parameters among different locations can be attributed to natural geological differences, varying land use practices, and the proximity of pollution sources. Nnemagadi consistently showed higher levels of most parameters compared to other locations, which may indicate localized sources of contamination or natural mineral deposits influencing the water quality.

4.3 Water Quality Analysis: Hardness and Ion Concentrations

Figure 2 and Table 3 presents the concentrations of hardness and ions in surface water from six locations: Nnemagadi, Iyiocha Ups, Iyiocha Ds, Idumuje, Iyi Enugu, and Ogiakpa. These values are compared against the WHO (2006) and NIS (2007) standards for water quality.

Table 3

Concentrations of hardness and ions in surface water compared with WHO (2006) and NIS (2007) standards
Parameters	Nnemagadi	Iyiocha Ups	Iyiocha Ds	Idumuje	Iyi Enugu	Ogiakpa	WHO (2006)	NIS (2007)
Total Hardness (mg/l)	35.00	18.00	10.00	20.00	10.00	8.00	100.00	150.00
Calcium Hardness (mg/l)	24.56	10.25	6.72	12.64	7.28	5.95	75.00	100.00
Magnesium Hardness (mg/l)	10.44	7.75	3.28	7.36	2.72	2.05	20.00
Sodium (mg/l)	7.65	5.31	2.27	4.38	2.82	1.65	200.00	200.00
Potassium (mg/l)	0.54	0.33	0.14	0.29	0.12	0.08	200.00	200.00

Total hardness measures the concentration of calcium and magnesium ions in water, reported as the equivalent quantity of calcium carbonate. In Nnemagadi, total hardness is 35.00 mg/l, while in Iyiocha Ups and Iyiocha Ds, the values are 18.00 mg/l and 10.00 mg/l, respectively. Idumuje and Iyi Enugu both show moderate values of 20.00 mg/l and 10.00 mg/l, with Ogiakpa having the lowest at 8.00 mg/l. According to WHO (2006) standards, the permissible limit is 100 mg/l, and NIS (2007) sets a limit of 150 mg/l. All sampled locations are well within these limits, indicating no significant concerns regarding water hardness. Calcium hardness represents the calcium ion concentration, essential for water quality evaluation. Nnemagadi has the highest calcium hardness at 24.56 mg/l. Iyiocha Ups and Iyiocha Ds show 10.25 mg/l and 6.72 mg/l, respectively. Idumuje records 12.64 mg/l, while Iyi Enugu and Ogiakpa have 7.28 mg/l and 5.95 mg/l, respectively. These values are considerably below the WHO (2006) and NIS (2007) limits of 75 mg/l and 100 mg/l. The data indicate the absence of calcium-related hardness issues in these water sources.

Magnesium hardness is another critical parameter for assessing water quality. The highest magnesium concentration is found in Nnemagadi at 10.44 mg/l, followed by Iyiocha Ups at 7.75 mg/l. Iyiocha Ds, Idumuje, Iyi Enugu, and Ogiakpa show lower values of 3.28 mg/l, 7.36 mg/l, 2.72 mg/l, and 2.05 mg/l, respectively. The WHO (2006) standard for magnesium is 20 mg/l. All observed values fall below this limit, suggesting minimal magnesium hardness concerns. Sodium concentration in water is an important factor for health and taste. Nnemagadi has the highest sodium level at 7.65 mg/l, with Iyiocha Ups and Iyiocha Ds at 5.31 mg/l and 2.27 mg/l, respectively. Idumuje, Iyi Enugu, and Ogiakpa show 4.38 mg/l, 2.82 mg/l, and 1.65 mg/l, respectively. Both WHO (2006) and NIS (2007) set the acceptable limit for sodium at 200 mg/l. The significantly lower values across all locations indicate no sodium-related issues in these water sources.

Potassium levels in water are typically low but essential to monitor. Nnemagadi has a potassium concentration of 0.54 mg/l. Iyiocha Ups and Iyiocha Ds report lower values of 0.33 mg/l and 0.14 mg/l. Idumuje, Iyi Enugu, and Ogiakpa show concentrations of 0.29 mg/l, 0.12 mg/l, and 0.08 mg/l, respectively. The permissible limit for potassium by WHO (2006) and NIS (2007) is 200 mg/l. The results indicate all locations have potassium concentrations well within safe limits, posing no health risk.

The comparison with WHO (2006) and NIS (2007) standards reveals that all parameters are within the acceptable limits set by these guidelines. Total hardness, calcium hardness, magnesium hardness, sodium, and potassium concentrations in all sampled locations comply with international and national standards, reflecting the overall good quality of the surface water in the study area. The observed total hardness levels in the study area are significantly lower than the WHO and NIS guidelines, suggesting that the water is soft and unlikely to contribute to scaling in plumbing or industrial systems (Bamigboye et al., 2020; Titilawo et al., 2020). The low hardness levels also indicate a reduced likelihood of adverse health effects related to excessive intake of calcium and magnesium (Olusola, 2020). The data shows that calcium and magnesium hardness levels are well below the permissible limits. Low calcium and magnesium concentrations indicate that the water will not contribute to conditions such as kidney stones, which can be exacerbated by high levels of these minerals (Ewuzie et al., 2021). This compliance with standards also suggests that the water is unlikely to affect the taste or contribute to scaling in household and industrial systems. Sodium and potassium levels in the water are also within acceptable limits, indicating that the water is safe for consumption with regard to these ions. Elevated sodium levels in drinking water can lead to hypertension and cardiovascular diseases, but the levels observed in the study area pose no such risks (Nwankwo et al., 2020). Similarly, potassium levels are well within safe limits, ensuring that the water does not pose any health risks associated with excessive potassium intake.

4.4 Analysis of Heavy Metal Concentrations in Surface Water

The analysis of surface water from various locations revealed the concentrations of heavy metals, including lead, cadmium, iron, copper, zinc, and nickel. Table 4 compares these concentrations with the World Health Organization (WHO, 2006) and Nigerian Industrial Standards (NIS, 2007) guidelines.

Table 4

Concentrations of heavy metals in surface water compared with WHO (2006) and NIS (2007) Standards
Parameters	Nnemagadi	Iyiocha Ups	Iyiocha Ds	Idumuje	Iyi Enugu	Ogiakpa	WHO (2006)	NIS (2007)
Lead (Pb) (mg/l)	0.002	0.003	<BDL	0.001	0.002	<BDL	0.01	0.01
Cadmium (Cd) (mg/l)	<BDL	<BDL	<BDL	<BDL	<BDL	0.001	0.003	0.003
Iron (Fe) (mg/l)	0.026	0.011	0.009	0.005	0.045	0.002	0.3	0.3
Copper (Cu) (mg/l)	0.019	<BDL	0.005	0.008	0.013	<BDL	2.0	2.0
Zinc (Zn) (mg/l)	0.307	0.227	0.083	0.514	0.065	0.027	3.0	3.0
Nickel (Ni) (mg/l)	<BDL	<BDL	<BDL	0.001	<BDL	<BDL	0.02	0.02

In this study, lead concentrations in surface water samples from Nnemagadi, Iyiocha Ups, Iyiocha Ds, Idumuje, Iyi Enugu, and Ogiakpa were measured and compared against WHO (2006) and NIS (2007) standards. The lead concentrations were found to be 0.002 mg/l in Nnemagadi and Iyi Enugu, 0.001 mg/l in Idumuje, and 0.003 mg/l in Iyiocha Ups. Lead levels in Iyiocha Ds and Ogiakpa were below the detection limit (BDL, < 0.001 mg/l). The average lead concentration across all sites was 0.002 mg/l, which is below the WHO and NIS guidelines of 0.01 mg/l. This indicates that the water samples from these locations are safe for consumption with respect to lead content, posing minimal health risks to the local population. The Maximum Contaminant Level Goal (MCLG) for cadmium set by the EPA is 0.005 mg/l to prevent potential health hazards. In this analysis, cadmium levels in surface water from Nnemagadi, Idumuje, Iyiocha Ups, Iyiocha Ds, and Iyi Enugu were all below the detection limit (BDL, < 0.001 mg/l). Ogiakpa showed a cadmium concentration of 0.001 mg/l, which is well below the MCLG of 0.005 mg/l. These findings suggest that cadmium contamination in these water sources is minimal, adhering to safety standards and posing no significant health risk to consumers.

The iron concentrations in the surface water samples were 0.026 mg/l in Nnemagadi, 0.011 mg/l in Iyiocha Ups, 0.009 mg/l in Iyiocha Ds, 0.005 mg/l in Idumuje, 0.045 mg/l in Iyi Enugu, and 0.002 mg/l in Ogiakpa. The average iron concentration was 0.016 mg/l, well below the recommended limit. Therefore, the water samples from these locations are aesthetically acceptable and safe for consumption concerning iron content. The WHO and NIS standards recommend a maximum iron concentration of 0.3 mg/l for drinking water. In this study, copper concentrations were measured as 0.019 mg/l in Nnemagadi, 0.008 mg/l in Idumuje, 0.013 mg/l in Iyi Enugu, 0.005 mg/l in Iyiocha Ds, and below the detection limit in Iyiocha Ups and Ogiakpa. The average concentration of copper was 0.011 mg/l, which is significantly lower than the permissible limit. This indicates that the water from these sources is safe for consumption with respect to copper content, posing no significant health risks or aesthetic issues. The WHO and NIS guidelines set the maximum permissible concentration of copper in drinking water at 2 mg/l.

The zinc concentrations in the surface water samples were 0.307 mg/l in Nnemagadi, 0.227 mg/l in Iyiocha Ups, 0.083 mg/l in Iyiocha Ds, 0.514 mg/l in Idumuje, 0.065 mg/l in Iyi Enugu, and 0.027 mg/l in Ogiakpa. The average zinc concentration was 0.204 mg/l, significantly lower than the guideline value of 3 mg/l. This ensures that the water is safe for consumption concerning zinc content and does not pose any significant health risks. The WHO and NIS guidelines recommend a maximum zinc concentration of 3 mg/l in drinking water. In this analysis, nickel levels were found to be below the detection limit (BDL, < 0.001 mg/l) in Nnemagadi, Iyiocha Ups, Iyiocha Ds, Iyi Enugu, and Ogiakpa. Idumuje recorded a nickel concentration of 0.001 mg/l. These values are well within the permissible limit of 0.02 mg/l, indicating that the water samples are safe for consumption with respect to nickel content. The WHO and NIS guidelines recommend a maximum nickel concentration of 0.02 mg/l in drinking water.

The analysis of heavy metals in surface water from Nnemagadi, Iyiocha Ups, Iyiocha Ds, Idumuje, Iyi Enugu, and Ogiakpa revealed that the concentrations of lead, cadmium, iron, copper, zinc, and nickel were all within the safe limits set by WHO (2006) and NIS (2007) standards. This indicates that the water from these locations is generally suitable for consumption and poses minimal health risks related to heavy metal contamination.

4.5 Correlation Analysis of Surface Water Quality Parameters

This study focuses on parameters such as pH, Temperature (Temp), Total Dissolved Solids (TDS), Conductivity (Cond), Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), Total Suspended Solids (TSS), Turbidity (Turb), Salinity (Sal), and Alkalinity (Alk). These parameters were measured and their interrelationships were analyzed through a correlation matrix shown in Table 5.

Table 5

Correlation matrix of water quality parameters
Parameter	pH	Temp (°C)	TDS (mg/L)	Cond (µS/cm)	DO (mg/L)	BOD (mg/L)	TSS (mg/L)	Turb (NTU)	Sal (mg/L)	Alk (mg/L as CaCO₃)
pH	1.00	-0.59	0.89	0.89	-0.51	-0.03	0.86	0.88	0.61	0.99
Temp (°C)	-0.59	1.00	-0.73	-0.76	0.31	-0.59	-0.56	-0.56	-0.40	-0.62
TDS (mg/L)	0.89	-0.73	1.00	1.00	-0.34	0.11	0.92	0.92	0.78	0.92
Cond (µS/cm)	0.89	-0.76	1.00	1.00	-0.35	0.14	0.91	0.91	0.77	0.92
DO (mg/L)	-0.51	0.31	-0.34	-0.35	1.00	-0.19	-0.06	-0.08	-0.33	-0.36
BOD (mg/L)	-0.03	-0.59	0.11	0.14	-0.19	1.00	-0.05	-0.06	-0.29	-0.03
TSS (mg/L)	0.86	-0.56	0.92	0.91	-0.06	-0.05	1.00	1.00	0.64	0.93
Turb (NTU)	0.88	-0.56	0.92	0.91	-0.08	-0.06	1.00	1.00	0.64	0.94
Sal (mg/L)	0.61	-0.40	0.78	0.77	-0.33	-0.29	0.64	0.64	1.00	0.62
Alk (mg/L as CaCO₃)	0.99	-0.62	0.92	0.92	-0.36	-0.03	0.93	0.94	0.62	1.00

The pH of water is a critical parameter that influences the solubility and availability of nutrients and heavy metals. The pH values showed a strong positive correlation with TDS (0.89), Conductivity (0.89), TSS (0.86), Turbidity (0.88), Salinity (0.61), and Alkalinity (0.99). These correlations suggest that as the pH increases, the concentrations of dissolved and suspended solids, as well as the overall alkalinity, tend to increase. This relationship can be attributed to the dissolution of minerals and salts at higher pH levels, which contributes to increased TDS and conductivity (Adebayo et al., 2021). Temperature is a fundamental physical parameter affecting chemical reactions and biological processes in water. It showed a negative correlation with most parameters except DO (0.31). The negative correlations with pH (-0.59), TDS (-0.73), and Conductivity (-0.76) indicate that higher temperatures might lead to lower concentrations of dissolved solids and reduced conductivity. This trend could be due to the enhanced evaporation and decreased solubility of salts at higher temperatures. The positive correlation with DO can be explained by the increased metabolic activities of aquatic organisms at higher temperatures, leading to higher oxygen demand and production (Ukah et al., 2020).

TDS and Conductivity are directly related as both measure the concentration of dissolved ions in water. Their perfect correlation (1.00) confirms this relationship. Both parameters also showed strong positive correlations with pH, TSS, Turbidity, Salinity, and Alkalinity. These correlations suggest that waters with high TDS and Conductivity are likely to have higher pH levels, more suspended solids, and greater turbidity. This can be attributed to the presence of more dissolved and particulate matter that contributes to both conductivity and turbidity. Dissolved Oxygen is vital for aquatic life and is an indicator of water's ability to support aquatic organisms. DO showed a negative correlation with most parameters, including pH (-0.51), TDS (-0.34), and Conductivity (-0.35), suggesting that higher levels of dissolved solids and conductivity may reduce oxygen availability. This trend can occur due to the increased biological oxygen demand in waters with higher concentrations of organic and inorganic matter, leading to oxygen depletion.

BOD measures the amount of oxygen required by microorganisms to decompose organic matter in water. BOD showed weak correlations with most parameters, except for a notable negative correlation with temperature (-0.59). This suggests that higher temperatures may reduce the BOD, possibly due to increased microbial activity that rapidly consumes available organic matter. However, the weak correlations with other parameters indicate that BOD is influenced by a variety of factors, including the presence of organic pollutants and microbial populations (Ukpai et al., 2020; Aladejana et al., 2021).

TSS and Turbidity are closely related, as suspended solids contribute to the cloudiness of water. Their perfect correlation (1.00) confirms this relationship. Both parameters showed strong positive correlations with pH, TDS, Conductivity, and Alkalinity, indicating that waters with higher suspended solids are likely to have higher pH levels, more dissolved solids, and greater overall alkalinity. This can be attributed to the presence of particulate matter that increases both TSS and turbidity, reflecting the presence of suspended and dissolved minerals (Talabi et al., 2020). Salinity measures the concentration of salt in water and showed positive correlations with pH (0.61), TDS (0.78), Conductivity (0.77), and Alkalinity (0.62). These correlations suggest that higher salinity is associated with higher pH levels and increased concentrations of dissolved ions, contributing to higher conductivity and alkalinity. This relationship is expected as salinity increases with the presence of dissolved salts, which also contribute to TDS and conductivity (Onwe et al., 2021). Alkalinity measures the water's ability to neutralize acids and is primarily influenced by the presence of bicarbonates, carbonates, and hydroxides. Alkalinity showed strong positive correlations with pH (0.99), TDS (0.92), Conductivity (0.92), TSS (0.93), and Turbidity (0.94). These correlations suggest that waters with higher alkalinity are likely to have higher pH levels, more dissolved and suspended solids, and greater turbidity. This can be attributed to the presence of alkaline compounds that contribute to both pH and alkalinity (Talabi et al., 2020).

4.6 Evaluation of Sodium Absorption Ratio (SAR) in Surface Water

Table 6 presents the SAR values for the analyzed water samples from six different locations: Nnemagadi, Iyiocha Ups, Iyiocha Ds, Idumuje, Iyi Enugu, and Ogiakpa. The SAR values for these samples range from 0.15 to 0.33, with an average of 0.24. These values indicate that the water from these locations is suitable for irrigation purposes, as an SAR value of less than 3 suggests no sodium problem.

Table 6

Sodium Absorption Ratio (SAR) values for analyzed water samples
	Na (mg/L)	Mg (mg/L)	Ca (mg/L)	Na (meq/L)	Mg (meq/L)	Ca (meq/L)	SAR
Nnemagadi	7.65	10.44	24.56	0.3326	0.8586	1.2255	0.3258
Iyiocha Ups	5.31	7.75	10.25	0.2309	0.6373	0.5115	0.3046
Iyiocha Ds	2.27	3.28	6.72	0.0987	0.2697	0.3353	0.1794
Idumuje	4.38	7.36	12.64	0.1904	0.6053	0.6307	0.2422
Iyi Enugu	2.82	2.72	7.28	0.1226	0.2237	0.3633	0.2263
Ogiakpa	1.65	2.05	5.95	0.0717	0.1686	0.2969	0.1487

SAR is a vital indicator for assessing the potential impact of sodium on soil properties, especially in agricultural settings. High sodium levels in irrigation water can lead to soil permeability issues and soil hardening, negatively affecting crop growth and yield (Moussa et al., 2020; Ukpai et al., 2020; Adebayo et al., 2021). Water with high sodium content can displace calcium and magnesium in the soil, reducing its structure and causing compaction (Ukpai et al., 2020; Aal et al., 2023). The SAR values in this study range between 0.15 and 0.33, all well below the threshold of 3. This indicates that the water samples from all analyzed locations are suitable for irrigation without the risk of sodium-induced soil degradation. Consequently, the use of this water for irrigation purposes will not lead to adverse effects on soil permeability or crop growth.

The observed SAR values are significantly lower than the critical value of 3, confirming that the water quality is within the acceptable range for agricultural use. These findings are consistent across all sampled locations, ensuring a uniform suitability for irrigation.

4.7 Hydrochemical Facies Analysis

The study employed four hydrochemical diagrams—Piper Trilinear, Durov, Schoeller, and Stiff—to comprehensively analyze the chemical composition and hydrochemical facies of water samples collected from the study area. These diagrams provided detailed insights into the predominant ion groups present in the water, offering a nuanced understanding of its hydrochemical characteristics.

The Piper diagram (Fig. 3) depicted two primary hydrochemical facies prevalent in the area: Ca-Mg-(Na)-Cl and Ca-Mg-(Na)-SO4. These facies indicate a composition dominated by calcium, magnesium, sodium, chloride, and sulfate ions. The Ca-Mg-(Na)-Cl facie is particularly indicative of saline water conditions, characterized by a higher concentration of chloride ions relative to alkaline earth metals such as calcium and magnesium (Aladejana et al., 2020; Talabi et al., 2020; Bolaji et al., 2021). This suggests potential influences from sources rich in sodium chloride, impacting the overall water chemistry.

Analysis using the Durov diagram (Fig. 4) revealed dominant facie groups, with Ca-Cl being the most prevalent. This facie underscores the significant presence of calcium and chloride ions in the water samples, which are typical characteristics of hard water types. The presence of Ca-HCO₃ + CO₃ facies indicates varying levels of bicarbonate and carbonate ions alongside calcium, contributing further to the water's chemical profile (Isibor & Aderogbin, 2020).

The Schoeller diagram (Fig. 5) provided a detailed breakdown of hydrochemical facies across different sampling points. Nnemagadi exhibited a Ca-Mg-HCO₃ + CO₃ facie, which correlates closely with the Piper diagram findings, highlighting a predominant presence of bicarbonate and carbonate ions in addition to calcium and magnesium. Other locations such as Iyiocha Ups, Iyiocha Ds, Idumuje, Iyi Enugu, and Ogiakpa demonstrated varying combinations of calcium, magnesium, chloride, sulfate, and bicarbonate ions. These variations underscore the diverse hydrochemical characteristics influenced by local geological formations and environmental factors specific to each sampling site.

Similarly, the Stiff diagram (Fig. 6) corroborated the presence of dominant facie groups observed in previous diagrams. Nnemagadi exhibited a Ca-Mg-HCO₃ + CO₃ facie (Fig. 6a), indicative of significant bicarbonate and carbonate ion concentrations alongside calcium and magnesium. In contrast, Iyiocha Ups displayed Mg-Ca-Cl and Mg-Ca-SO₄ facies (Fig. 6b), highlighting the prevalence of chloride and sulfate ions alongside calcium and magnesium. This pattern repeated across Iyiocha Ds (Fig. 6c), Idumuje (Fig. 6d), Iyi Enugu (Fig. 6e), and Ogiakpa (Fig. 6f), each demonstrating specific combinations of calcium, magnesium, chloride, sulfate, and bicarbonate ions that characterize their respective hydrochemical facies.

The integrated analysis of the Piper, Durov, Schoeller, and Stiff diagrams consistently indicates that the water samples exhibit characteristics of hard water. This conclusion is primarily drawn from the high concentrations of calcium and magnesium ions observed across all diagrams. The presence of chloride and sulfate ions in significant proportions further contributes to the overall chemical profile, reflecting influences from both natural geological formations and potential anthropogenic activities in the study area.

The chemical analysis of water resources in Obomkpa and its surroundings, located in Aniocha North Local Government Area of Delta State, Western Niger Delta, Nigeria, reveals several key parameters influencing its suitability for various uses, particularly agriculture and potential domestic consumption. The water is characterized as slightly acidic with a mean pH value of 5.89, necessitating treatment to elevate it to safe drinking levels per WHO and NIS standards.

The Total Dissolved Solids (TDS) and Electrical Conductivity (EC) levels are within safe limits for drinking, averaging 28.62 mg/L and 46.82 µS/cm respectively. Dissolved Oxygen (DO) is adequate at 4.98 mg/L, while Biochemical Oxygen Demand (BOD) is low at 1.21 mg/L, indicating favorable conditions for aquatic life. Total Suspended Solids (TSS), Turbidity, and Salinity are generally acceptable, except for elevated turbidity in Nnemagadi, necessitating treatment. Anion analysis shows Sulphate, Nitrate, Bicarbonate, and Chloride levels averaging 5.11 mg/L, 0.10 mg/L, 27.74 mg/L, and 8.27 mg/L respectively, well within safe limits. These originate from natural sources like gypsum and fertilizers. Cations Calcium, Magnesium, Sodium, and Potassium are also within safe limits, with mean values of 11.23 mg/L, 5.60 mg/L, 4.01 mg/L, and 0.25 mg/L respectively. Heavy metal analysis indicates Iron and Copper are safe at 0.016 mg/L and 0.011 mg/L respectively, while Zinc exceeds the acceptable limit at 0.204 mg/L, necessitating treatment. Nickel is below detection limits in most samples, indicating low levels suitable for consumption.

The area's water quality analysis suggests suitability for irrigation based on an EC mean of 46.82 µS/cm, TDS mean of 28.62 mg/L, and Sodium Absorption Ratio (SAR) mean of 0.24, aligning with Wilcox's suitability classifications. Correlation analysis reveals varied relationships among physiochemical parameters, with DO and temperature showing negative correlations with others, suggesting different environmental sources. pH negatively correlates with temperature, DO, and BOD, while other parameters exhibit positive correlations, indicating shared sources. Hydrochemical facies analysis using the Piper Trilinear diagram identifies predominant water types as Ca-Mg-(Na)-Cl and Ca-Mg-(Na)-SO₄, categorizing the water as hard due to elevated Ca and Mg concentrations, which are favorable for consumption compared to soft water types.

Given the reliance of approximately 80% of the local workforce on surface water for agricultural activities, there is an urgent need to assess water quality amidst potential anthropogenic contamination. This study contributes to the body of knowledge by providing a detailed hydrogeochemical analysis of surface water in Obomkpa, aiming to inform targeted remediation strategies to enhance water quality for various applications.

In light of the above conclusion, the following recommendations are proposed to improve water quality for various uses in Obomkpa and its surrounding areas:

Acidity Reduction: To address the issue of low pH (mean of 5.89), which renders the water slightly acidic, lime (calcium hydroxide) should be added to neutralize the acidity. This will help in raising the pH to acceptable levels for drinking water as per WHO and NIS standards.

Zinc Concentration Control: Since the concentration of zinc exceeds acceptable limits (mean of 0.204 mg/l), it is essential to install advanced filtration systems such as reverse osmosis or activated carbon filters. These systems can effectively reduce zinc levels, making the water safer for consumption.

Turbidity Reduction: Elevated turbidity levels, particularly in Nnemagadi, necessitate treatment through sedimentation followed by sand filtration. This process will remove suspended solids and reduce turbidity to acceptable levels.

Regular Monitoring and Assessment: Establish continuous water quality monitoring programs to regularly assess key parameters such as pH, total dissolved solids (TDS), electrical conductivity (EC), dissolved oxygen (DO), biochemical oxygen demand (BOD), turbidity, and heavy metal concentrations. This will help in early detection of any deviations from acceptable standards and prompt remediation.

Community Awareness and Education: Public Education Campaigns: Implement community education programs to raise awareness about the sources of water pollution and the importance of maintaining water quality. Educating the community on proper waste disposal, reducing agricultural runoff, and preventing industrial discharges into water bodies will help in minimizing pollution sources.

Implementation of Sustainable Practices: Adopt Integrated Water Resources Management (IWRM) practices to ensure the sustainable use of water resources. This includes promoting the reuse and recycling of wastewater, protecting natural water bodies through conservation efforts, and implementing pollution control measures at the source

Author Contribution

E.S. Chinemelu: designed and performed the experiments; analyzed and interpreted the results and wrote the manuscript.O.O. Omoirabor: designed and performed the experiments; analyzed and interpreted the results and worked on the manuscript.

Acknowledgement

We are appreciative of R.N. Okpoto’s assistance during sample collection. We also extend our special gratitude to two other anonymous reviewers for their insightful critiques and recommendations, which significantly improved the quality of this work.

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Hydrogeochemical Characterization and Water Quality Assessment of Surface Water Resources in Obomkpa, Western Niger Delta, Nigeria

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Abstract

Figures

1. Introduction

2. Research area and geology of the study area

3. Methodology

3.1 Sampling and Analysis

4. Results and Discussion

4.1 Assessment of Water Quality Parameters in Surface Water Samples

4.2 Evaluation of Anion Concentrations in Surface Water Samples

4.3 Water Quality Analysis: Hardness and Ion Concentrations

4.4 Analysis of Heavy Metal Concentrations in Surface Water

4.5 Correlation Analysis of Surface Water Quality Parameters

4.6 Evaluation of Sodium Absorption Ratio (SAR) in Surface Water

4.7 Hydrochemical Facies Analysis

5. Conclusion

Declarations

Author Contribution

Acknowledgement

References

Additional Declarations

Status:

Version 1