Sustainability of Groundwater for Irrigation Purposes in Semi-arid Parts of Namibia

The groundwater quality data from 1,137 boreholes in 10 regions of Namibia were assessed for sodium adsorption ratio (SAR), Kelly's ratio (KR), sodium percentage (Na%), magnesium adsorption ratio (MAR), total hardness (TH), soluble sodium percentage (SSP), potential salinity (PS), electrical conductivity (EC), and total dissolved solids (TDS) to determine the suitability for the irrigation. The groundwater was classified as follows: all the regions' groundwater shows the TH as very hard water of >4.6 meq/l, PS as not suitable for irrigation (>3 meq/l), and EC as very highly (0.75–2.25 dS/m). However, Na%: 10% of regions have doubtful water (>80%), MAR: 30% of regions are not recommended for irrigation (>50 meq/l), and TDS: 90% of the regions have slightly moderate (450–2,000 mg/l) and 10% have groundwater that is unsuitable for agricultural purposes (>2,000 mg/l). The unsuitability of groundwater for irrigation could be due to higher concentrations of K+, Mg2+, Ca2+, and Cl− that has exceeded the FAO guideline for irrigation. Some groundwater qualities had inverse classification such as SAR all regions have excellent groundwater (<10 meq/l), KR: 90% of regions have safe water (<1 meq/l), Na%: 50% of regions have good groundwater (20–40%), 40% of the regions have permissible water (40–80%), and MAR: +70% of region's water is recommended for irrigation (<50 meq/l).

Application of Multivariate Approaches to the Hydro-chemical Assessment of the Ghodaghodi Lake, Sudurpaschim Province, Nepal

Wetlands are considered the most diverse and productive ecosystems in the world, providing life-sustaining ecological services. Hydrochemical variables of the Ghodaghodi Lake situated in Far west Nepal were studied using multivariate statistical approaches to investigate the characteristics of water quality of the lake. A total of 10water samples were collected and analyzed for water temperature, pH, electrical conductivity, total dissolved solids, total hardness, salinity, dissolved oxygen, major ions, and dissolved Si in the pre-monsoon season during 2017.The water quality assessment was carried out by applying sodium percentage, sodium adsorption ratio, permeability index, Kelly’s ratio, magnesium adsorption ratio, action ratio of soil structural stability, and water quality index. Multivariate statistical techniques were used to evaluate the geochemical and anthropogenic processes and to identify factors influencing the ionic concentrations. The results revealed that the water was slightly alkaline with low ionic strength and remarkable spatial variations. The hydrochemistry of the lake was mainly controlled by rock weathering as the dominant Ca2+-HCO3- facies. The principal component analysis provided three major components exhibiting the diverse sources of natural and anthropogenic chemicals, including agricultural fertilizers, leakage of sewages near the human settlements, etc. The measured hydrochemical parameters indicate that lake water lies within the safe drinking water and irrigational standards. However, special consideration should be taken to control the concentrations of NO3- due to increasing anthropic activities.

Physicochemical properties of groundwater in parts of Irun Akoko, Ondo State, Nigeria

Ten groundwater samples from hand dug wells were collected at Irun Akoko within the basement complex of part of southwestern Nigeria. The aim of the study was to determine the groundwater suitability for both drinking and irrigation purposes. The groundwater samples were analysed for some physical and chemical constituents including pH, Total Dissolved Solids (TDS), turbidity, Na, Ca, Mg, K, Cl, SO4, PO4 and NO3. The pH (7.0 – 7.9) and TDS (12.26 – 19.35 mg/l) of the groundwater indicate that the water is neutral to slightly alkaline and fresh respectively. The order of relative abundance for concentration of cations in the groundwater is K>Ca>Na>Mg, while that of anions is Cl>SO4>NO3>PO4. The concentrations of potassium in about 90% and chloride in about 40 % of the samples were above the World Health Organization (WHO) standard for drinking water. Other hydro-geochemical parameters Ca, Mg, Na, SO4, PO4 and NO3 falls within the WHO standards. Values of Sodium Absorption Ratio (SAR) classified the water as excellent for irrigation purposes. The Soluble Sodium Percentage (SSP) values classified eighty percent of the water to be of good quality and the remaining samples as fair for irrigation purposes. However, using the Magnesium Adsorption Ratio (55.0 – 68.9 %) the samples may have hazardous effects on the soil. Generally, groundwater in the study area is suitable for both domestic and irrigation uses.

Assessment of Water Quality Status of Chandrabhaga River at Rishikesh, Dehradun, Uttarakhand, India

In the background of the ambitious ‘National Mission for Clean Ganga’ to clean, conserve and protect the River Ganga in a comprehensive manner, this study was undertaken to evaluate the status of Water Quality of Chandrabhaga river at Rishikesh, district Dehradun, India, between the Dhalwala bridge area and Mayakund area where it merges with the river Ganga, affecting adversely its water quality. The characteristics of Chandrabhaga river water were assessed during July to September 2017 by monitoring the water quality at most garbeged and contaminated five locations by determining physicochemical and biological parameters and metal ions. The observed values of dissolved oxygen (DO) varied from 0.4 to 1.29 mg/L, such a low DO, high biological oxygen demand (BOD, 21 ± 2.64 to 56 ±6.08 mg/L) and much high Coliform (1760 ±13.23 to3180 ±27.61 MPN/ 100 ml) at all the locations reflects the poor water quality of Chandrabhaga River. Recorded values of total dissolved solid (TDS), electrical conductivity (EC), total hardness (TH), alkalinity, phosphate, sodium, potassium and calcium exceeded the WHO standards. Pearson’s correlation analysis revealed the highly positive correlations all the time between EC and TDS, TH and TDS, TH and EC, while during high flow period good correlations were recorded between alkalinity and pH, TDS, EC and TH. Irrigation water quality parameters such as soluble sodium percentage (SSP), sodium adsorption ratio (SAR), magnesium adsorption ratio (MAR) and Kelly’s Ratio was evaluated to test the suitability of river water for irrigation purpose.

An appraisal of geohydrological status and assessment of groundwater quality of Indpur Block, Bankura District, West Bengal, India

The present work aimed to evaluate the overall hydro-geological status of Indpur block, Bankura district, West Bengal, India. Despite of having adequate annual precipitation, south-western districts of the state of West Bengal, India, are considered to be a significantly water-stressed area of the state. This is because of unfavorable geological setting near to subsurface occurrence of impervious lithology and inundated nature of surface drainage pattern. The study was carried out both in pre- and post-monsoon seasons of 2019 to obtain an updated current status on concentration and spatiotemporal fluctuations of controlling ions of the subsurface water. Estimation of major physicochemical parameters and specific qualitative chemical characterization of groundwater were rated through field and laboratory studies. Water samples were collected from twenty-two equidistantly scattered tube wells in the block. Seasonal variations of water table elevation heads and subsurface shift of predominant recharge zones of the block were also demarked. Drinking, domestic and irrigation suitability of the block water were measured by the estimation of parameters such as Sodium Adsorption Ratio (SAR), Magnesium Adsorption Ratio (MAR), Soluble Sodium Percentage (SSP), Residual Sodium Carbonate (RSC), Permeability Index (PI), Total Hardness (TH) and Kelly’s ratio (KR) and piper trilinear plots. Sustainable non-availability of groundwater seems to be the major problem of the studied area, which intern resulted in overexploitation, mostly for cultivation practices causing considerable depletion of its suitability as drinking and irrigation. Further, results show that suitability of the water both for domestic and irrigation of the studied area may be termed as ‘good’ to ‘moderate’ with a few exceptions on a local scale. Judging by every parameter, it can be stated that groundwater of Indpur block is not much suitable for drinking purposes.

Assessment of Groundwater for Irrigation Using (IWQI) Model, Located in Al-Nimrud Region at Southeastern of Mosul City, Iraq

The study aimed to understand the quality of groundwater in Al-Nimrud region south-eastern part of Mosul city, Iraq. Groundwater samples from 10 wells were collected during the dry season and analyzed for their physical and chemical properties using standard laboratory methods. From the analyzed data, some parameters like sodium adsorption ratio (SAR), sodium percentage (Na%), potenial salinity (PS), residual sodium carbonate (RSC), magnesium adsorption ratio (MAR), permeability index (PI) and Kellys ratio (KR) were calculated for each water sample to know the irrigational fitness and irrigation water quality index (WQI) was applied to the analytical results of the parameters to obtain a single value that was used to rank the groundwater at each well for agricultural uses. The results showed a high levels of salts for most of the water samples studied, where the average values of EC ranged between (1.64 to 5.069) dS. m -1 . Also, the estimated parameters such as Na%, SAR, PI, KR were within the appropriate levels for irrigation, while the values of MAR, PS for most of the samples were within the inappropriate limits for irrigation. Also, the results of the WQI values showed that the groundwater quality falls between the category of severe to low restrictions, therefore the use of most of the water for irrigation in the study area is likely to lead to the problem of salinity in soils with heavy texture.

Chemical Characteristics of the Karmanasha River Water and Its Appropriateness for Irrigational Usage

Water is a prime natural resource and precious national asset and one of the chief constituents of the environment. The chemical characteristics play a key role in terms of ecological and economic perspectives in the river water. The characterization and evaluation of river water quality in the Karmanasha River is necessary due to its immense importance in the livelihood of the people in the core urban areas of Kathmandu valley, Nepal. In this study, the surface water samples were collected from 16 sites with a 0.5 km interval to characterize and evaluate the water quality mainly from the perspective of its irrigational usage. The assessment was carried out by applying electrical conductivity (EC), sodium percentage (Na%), sodium adsorption ratio (SAR), permeability index (PI), Kelly’s ratio (KR), magnesium adsorption ratio (MAR), cation ratio of soil structural stability (CROSS), Wilcox diagram and water quality index (WQI) including the general hydrochemistry. The general hydrochemistry of river water indicates slightly alkaline in nature with mean pH value 8.07, and the dominance order of major ions follows the pattern of Ca2+>Mg2+>Na+>K+ for cations, and HCO3->Cl->NO3- for anions. Furthermore, the results revealed that the water is safe for irrigation purposes based on EC, Na%, SAR, KR, MAR, CROSS, and Wilcox diagram. The results also specified that no severe degradation in water, however, the low DO, and high BOD and COD values than that of the standard value prescribed by Nepal Drinking Water Quality Standard, signify the anthropogenic signature in the river water. This study provides the baseline information about the WQI and suitability of irrigation water quality, and further in-depth studies are required at spatiotemporal levels to get in-depth insights about the ecological health of the river.

GROUNDWATER QUALITY MODELING FOR SUITABILITY FOR IRRIGATION PURPOSES IN OIL PRODUCING AREAS OF KHANA AND GOKANA LOCAL GOVERNMENT AREAS OF RIVERS STATE, NIGERIA

This study is aimed at modeling groundwater quality for irrigation purposes in oil producing areas of Khana and Gokana Local Government areas of Rivers State, Nigeria. A random sampling approach was adopted in groundwater sampling in Khana and Gokana local government areas of Rivers State. Groundwater samples were collected from a total of twenty-two (22) boreholes in the area. Ten (10) residential boreholes were sampled in Khana while 12 boreholes were sampled in Gokana local government area. Various indices were used to determine the quality of groundwater for irrigation in the study area such as Electrical Conductivity (EC), Sodium Adsorption Ratio (SAR), Permeability Index (PI), Percent Sodium (%Na), Magnesium Adsorption Ratio (MAR), Kelly’s Ratio (KR) and Potential Soil Salinity (PS). In Khana area, all the water samples have PI values which render the groundwater unsuitable for irrigational purposes. Meanwhile, in Gokana, the groundwater samples show good to excellent quality for irrigation purposes. A high permeability index enhances crops yield, because the soils becomes more aerated and allows flow to occur easily, carrying plant nutrients from one part of the soil to the other. All groundwater samples in the area plotted in the C1-S1 (low sodium hazard and low salinity), C2-S1 (low sodium hazard and moderate salinity) and C3-S1 (low sodium hazard and high salinity) category which represents low sodium hazard and low salinity hazards and are therefore suitable for irrigation.

Evaluation of Irrigation Quality of Groundwater in Wamba Sheet 210, North Central Nigeria

An evaluation of irrigation quality of groundwater from shallow aquifers within Wamba Sheet 210 in Nasarawa State, North Central Nigeria was carried out. The area is located between Latitudes 8°30’N and 9°00’N, and Longitudes 8°30’E and 9°00’E, covering about 3,025 Km2. It is underlain by rocks belonging to the Basement Complex, the Younger Granites, and Cretaceous sedimentary rocks. The results of field tests and laboratory analysis were used in assessing the suitability of groundwater found in the area for irrigation. Values obtained for Sodium Adsorption Ratio (SAR), Soluble Sodium Percentage (SSP), Magnesium Adsorption Ratio (MAR) and Kellys Ratio (KR) were 0.97 - 3.43, 8.18 - 81.76%, 8.03 - 80.22 and 0.04 - 3.43 respectively. These indices are largely within the safe limits for irrigation with very little likelihood that salinity hazards will develop.

ASSESSMENT OF SURFACE WATER QUALITY OF ERO DAM FOR IRRIGATION PURPOSE

The physicochemical parameters of surface water surface of Ero Dam for irrigation were assessed. Water samples were selected from three locations (upstream, downstream and control). Tested parameters for water samples are pH, electrical conductivity (EC), total dissolved solids (TDS), calcium (Ca2+), magnesium (Mg2+), sodium (Na+), potassium (K+), chloride (Cl-), carbonate (C03-), bicarbonate (HC03-), boron (B), sulphate (S042-), nitrate (NO3-N) and phosphate (PO4-P). The samples were determined in accordance with the American Public Health Association standards. Data were analysed using descriptive statistics. Evaluation of surface water quality of Ero Dam was carried out using different irrigation indices methods such as sodium adsorption ratio (SAR), residual sodium carbonate (RSC), sodium percentage (Na %), potential salinity (PS), The Soluble sodium percentage (SSP), Kelly ratio (KR), magnesium adsorption ratio (MAR) and permeability index (PI) and compared with standard limits. The findings indicated that the concentrations of the Ca2+, Mg2+, Na+, K+, Cl-, C03-, HC03-, B, S042-, NO3-N and PO4-P were within the acceptance limits for irrigation purposes except K+ that above the limits specified. Results indicated that majority, 87.5% of irrigation indices fall under excellent or suitable and classified as salinity (C1) and SAR (S1) which was known as (CISI). Hence, there are none degree of restriction in the application Ero Dam water quality for irrigation. Therefore, the results were concluded, that the study area surface water quality was suitable for irrigation.