Assessment of temporal variation in water quality of some important rivers in middle Gangetic plains, India

The study explains water quality of three important tributaries of the Ganga River in the middle Gangetic plains in India. Seasonal changes in the water quality of the studied rivers: Gandak, Ghaghra, and Sone were observed. During monsoon, several water quality parameters show considerable changes due to increased runoff from the catchments and other seasonal factors. Multivariate discriminant analysis delineated a few parameters responsible for temporal variation in water quality. Seasonal variation in water quality of the Gandak River was rendered by seven parameters??turbidity, sulfate, pH, phosphate, water temperature, total alkalinity, and sodium, while total alkalinity and water temperature were responsible for seasonal discrimination in water quality of Ghaghra River. Water temperature, turbidity, total dissolved solids, total suspended solids, calcium, and phosphate were important for seasonal discrimination in water quality of Sone River. The seasonal changes in water quality of the rivers were due to seasonal effects and catchment characteristics. The discriminant functions classified most of the cases correctly.     

Assessment of groundwater vulnerability in the coastal region of Oman using DRASTIC index method in GIS environment

A study was carried out to develop a vulnerability map for Barka region in the North Batina of Oman using DRASTIC vulnerability index method in GIS environment. DRASTIC layers were created using data from published reports and the seven DRASTIC layers were processed by the ArcGIS geographic information system. Finally, DRASTIC maps were created for 1995 and 2004 to understand the long-term changes in the vulnerability index. DRASTIC vulnerability maps were evaluated using groundwater quality data such as chemical and biological parameters. DRASTIC vulnerability maps of 1995 and 2004 indicate that the northern part of Barka is more vulnerable to pollution than southern part and the central part of Barka also shows high relative vulnerability which is mostly related to the high conductivity values. Moreover, the changes in water level due to high abstraction rate of groundwater reflect in the vulnerability maps and low vulnerability area is increased in the southern part during 2004 compared to 1995. Moreover, regional distribution maps of nitrate, chloride and total and fecal coliforms are well correlated with DRASTIC vulnerability maps. In contrast to this, even though DRASTIC method predicted the central part of the study region is highly vulnerable, both chemical and biological parameters show lower concentrations in this region compared to coastal belt, which is mainly due to agricultural and urban development. In Barka, urban development and agricultural activities are very high in coastal region compared to southern and central part of the study area. Hence, this study concluded that DRASTIC method is also applicable in coastal region having ubiquitous contamination sources.     

Groundwater resource assessment, categories, and typologies: case study, Andhra Pradesh, India

In India, groundwater assessment units are classified as overexploited areas, critical areas, semi-critical, or safe areas based on the stage of groundwater development and long-term water level trends. Intuitively, in the safe units, wells are expected to function and have good yields. Besides, in the safe units, new wells are expected to be successful. Conversely, the expectation of a successful well or wells with good yields is much lesser in the overexploited units. However, when these expectations are not met in the field, doubts are raised about the quality of assessment and its usefulness, and there is outright distrust on the agencies assessing groundwater resource by the common man as well as on the planners, administrators, and the politicians. Therefore, there is a need to present the results in a way that does not create confusion. One of the methods is to combine the assessment results with aquifer characters using geographic information system (GIS); when this is done, a whole set of newer classes emerge, which can be mapped. These classes are termed as groundwater typologies in this study. Each typology has some characteristics or traits in common, which include basic aquifer character as well as the stage of groundwater development. Thus, a class may be safe, but if the aquifer is poor, then it is separated from a class that is safe and where the aquifer is good and so on. In Andhra Pradesh, which is taken as the case study for this purpose, eight main typologies emerged, and two of these main typologies were further divided into four subtypologies each. This new way of understanding the pattern of groundwater abstraction (using GIS) has a better visual impact. Groundwater typologies are found to be much more rational and useful in developing management strategies, rather than simple listing as overexploited areas, critical areas, semi-critical areas, and safe areas as is commonly done. The typologies so delineated indicate on the map (or table) that balanced usable groundwater is in between 5 and 6 bcm/a as against the estimated balance of 20.5 bcm/a, and it is largely in poor hard rock type of aquifers, which occupy about a third of the area of the state.     

Groundwater quality assessment in the village of Lutfullapur Nawada, Loni, District Ghaziabad, Uttar Pradesh, India

The groundwater quality for drinking, domestic and irrigation in the village Lutfullapur Nawada, Loni, district Ghaziabad, U.P., India, has been assessed. Groundwater samples were collected, processed and analyzed for temperature, pH, conductivity, salinity, total alkalinity, carbonate alkalinity, bicarbonate alkalinity, total hardness, calcium hardness, magnesium hardness, total solids, total dissolved solids, total suspended solids, nitrate-nitrogen, chloride, fluoride, sulfate, phosphate, silica, sodium, potassium, calcium, magnesium, total chromium, cadmium, copper, iron, nickel, lead and zinc. A number of groundwater samples showed levels of electrical conductivity (EC), alkalinity, chloride, calcium, sodium, potassium and iron exceeding their permissible limits. Except iron, the other metals (Cr, Cd, Cu, Ni, Pb, and Zn) were analyzed below the permissible limits. The correlation matrices for 28 variables were performed. EC, salinity, TS and TDS had significant positive correlations among themselves and also with NO (3) (-) , Cl(-), alkalinity, Na(+), K(+), and Ca(2+). Fluoride was not significantly correlated with any of the parameters. NO (3) (-) was significantly positively correlated with Cl(-), alkalinity, Na(+), K(+) and Ca(2+). Chloride also correlated significantly with alkalinity, Na(+), K(+) and Ca(2+). Sodium showed a strong and positive correlation with K(+) and Ca(2+). pH was negatively correlated with most of the physicochemical parameters. This groundwater is classified as a normal sulfate and chloride type. Base-exchange indices classified 73% of the groundwater sources as the Na(+)-SO (4) (2-) type. The meteoric genesis indices demonstrated that 67% of groundwater sources belong to a deep meteoric water percolation type. Hydrochemical groundwater evaluations revealed that most of the groundwaters belong to the Na(+)-K(+)-Cl(-)-SO (4) (2-) type followed by Na(+)-K(+)-HCO (3) (-) type. Salinity, chlorinity and SAR indices indicated that majority of groundwater samples can be considered suitable for irrigation purposes.     

Pesticide residues in vegetable samples from the Andaman Islands, India

Vegetable samples of brinjal, okra, green chilli, crucifers, and cucurbits collected from farmers' field were tested for the presence of organochlorine (OC), organophosphorus (OP), and synthetic pyrethroid (SP) compounds using a gas chromatograph equipped with electron capture and flame thermionic detectors. Of the samples tested, 34.0 % were found to have pesticide residues. Among the OC compounds, α-endosulfan, β-endosulfan, and endosulfan sulfate were detected in 14.5 % of the samples with residues. These were taken from crucifer, okra, green chilli, and cucurbit samples. SP compound residues, such as α-cypermethrin, fenvalerate I, fluvalinate I, deltamethrin, and λ-cyhalothrin were detected in 32 % of the samples with residues. OP compound residues such as chlorpyrifos, profenofos, monocrotophos, triazophos, ethion, dimethoate, and acephate were found in 54 % of the samples with residues, which were taken from all vegetable samples. Of the positive samples, 15.3 % were found to contain residues exceeding the prescribed maximum residue limit. The average pesticide residue content across all the vegetable samples was 0.108 ppm, with values ranging from 0.008 to 2.099 ppm. Multiple residues of more than one compound were detected in 34.1 % of samples containing residues.     

Assessment of drinking water quality using ICP-MS and microbiological methods in the Bholakpur area,Hyderabad, India

A total of 16 people died and over 500 people were hospitalized due to diarrhoeal illness in the Bholakpur area of Hyderabad, India on 6th May 2009. A study was conducted with immediate effect to evaluate the quality of municipal tap water of the Bholakpur locality. The study consists of the determination of physico-chemical properties, trace metals, heavy metals, rare earth elements and microbiological quality of drinking water. The data showed the variation of the investigated parameters in samples as follows: pH 7.14 to 8.72, EC 455 to 769 μS/cm, TDS 303.51 to 515.23 ppm and DO 1.01 to 6.83 mg/L which are within WHO guidelines for drinking water quality. The water samples were analyzed for 27 elements (Li, Be, B, Na, Mg, Al, Si, K, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Ba and Pb) using inductively coupled plasma-mass spectrometry (ICP-MS). The concentrations of Fe (0.12 to 1.13 mg/L), Pb (0.01 to 0.07 mg/L), Cu (0.01 to 0.19 mg/L), Ni (0.01 to 0.15 mg/L), Al (0.16 to 0.49 mg/L), and Na (38.36 to 68.69 mg/L) were obtained, which exceed the permissible limits of the World Health Organization (WHO) for drinking water quality guidelines. The remaining elements were within the permissible limits. The microbiological quality of water was tested using standard plate count, membrane filtration technique, thermotolerant coliform (TTC), and most probable number (MPN) methods. The total heterotrophic bacteria ranged from 1.0 × 10⁵ to 18 × 10⁷ cfu/ml. Total viable bacteria in all the water samples were found to be too numerable to count and total number of coliform bacteria in all water samples were found to be of order of 1,100 to >2,400 MPN index/100 ml. TTC tested positive for coliform bacteria at 44.2°C. All the water samples of the study area exceeded the permissible counts of WHO and that (zero and minimal counts) of the control site (National Geophysical Research Institute) water samples. Excessively high colony numbers indicate that the water is highly contaminated with microorganisms and is hazardous for drinking purposes. Bacteriological pollution of drinking water supplies caused diarrhoeal illness in Bholakpur, which is due to the infiltration of contaminated water (sewage) through cross connection, leakage points, and back siphoning.     

Groundwater quality assessment based on rough sets attribute reduction and TOPSIS method in a semi-arid area, China

In order to enrich and improve the groundwater quality assessment system, a new coupled assessment model based on rough set attribute reduction and the technique for order preference by similarity to ideal solution (TOPSIS) was proposed. The proposed model was applied in the groundwater quality assessment of a semi-arid area, northwest China. The results show that most chemical indices except NH (4) (+) , F(-), and Mn meet the Standards for Drinking Water of China and the groundwater quality overall is good. All assessed water samples are found to be fit for human consumption according to the comprehensive assessment results. Rough set attribute reduction for groundwater quality assessment is practical. The assessment results after attribute reduction show a good consistency with those before attribute reduction. Rough set attribute reduction and TOPSIS evaluation coupled model is clear in ideas and simple in calculation, and evaluation results are reasonable as well. The coupled model can be applied to solve many multiple criteria decision making problems such as groundwater quality assessment.     

Pesticide residues in river Yamuna and its canals in Haryana and Delhi, India

Yamuna, a prominent river of India covers an extensive area of 345,843 km(2) from Yamunotri glacier through six Indian states. Residues of organochlorine pesticides (OCPs) namely, isomers of HCH and endosulfan, DDT and its metabolites, aldrin, dieldrin, were analysed in water of river Yamuna along its 346 km stretch passing through Haryana-Delhi-Haryana and the canals originating from it. beta-HCH, p.p'-DDT, p.p'-DDE and p.p'-DDD had maximum traceability in test samples (95-100%) followed by gamma-HCH, alpha-HCH and o.p'-DDD (60-84%) and o.p'-DDT, delta-HCH and o.p'-DDE (7-30%) while aldrin, dieldrin, alpha and beta endosulfan remained below detection limits (BDL). The concentration of SigmaHCH and SigmaDDT at different sites of the river ranged between 12.76-593.49 ng/l (with a mean of 310.25 ng/l) and 66.17-722.94 ng/l (with a mean of 387.9 ng/l), respectively. In canals the values were found between 12.38-571.98 ng/l and 109.12-1572.22 ng/l for SigmaHCH and SigmaDDT, respectively. Water of Gurgaon canal and Western Yamuna canal contained maximum and minimum concentration, respectively both of SigmaHCH and SigmaDDT residues. Sources of these pesticides and suggested measures to check pesticide pollution of this major Indian river, keeping in view its vital link with life, are discussed in this paper.     

Organochlorine Pesticide Residues in Milk and Blood of Women from Anupgarh, Rajasthan, India

Anupgarh is the most fertile area of Rajasthan state where a variety of seasonal crops are grown. The availability of three manmade canals has enhanced the agricultural activities in this area. The farmers use huge amounts of pesticides to increase the crop productivity. Exposure of humans to these hazardous chemicals occurs directly in the fields and indirectly due to consumption of contaminated diet, or by inhalation or by dermal contact. The organochlorine pesticides are reported to be lipophilic and their presence in human milk and blood has been documented in different parts of the world. Blood and milk samples were collected from lactating women who were divided into four groups on the basis of different living standards viz residence area, dietary habits, working conditions and addiction to tobacco. The level of total organochlorine pesticides in blood ranged from 3.319mg/L—6.253mg/L while in milk samples it ranged from 3.209Mdash;4.608 mg/L. The results are in concurrence with the reports from other countries.     

Stochastic landslide vulnerability modeling in space and time in a part of the northern Himalayas, India

Little is known about the quantitative vulnerability analysis to landslides as not many attempts have been made to assess it comprehensively. This study assesses the spatio-temporal vulnerability of elements at risk to landslides in a stochastic framework. The study includes buildings, persons inside buildings, and traffic as elements at risk to landslides. Building vulnerability is the expected damage and depends on the position of a building with respect to the landslide hazard at a given time. Population and vehicle vulnerability are the expected death toll in a building and vehicle damage in space and time respectively. The study was carried out in a road corridor in the Indian Himalayas that is highly susceptible to landslides. Results showed that 26% of the buildings fall in the high and very high vulnerability categories. Population vulnerability inside buildings showed a value >0.75 during 0800 to 1000 hours and 1600 to 1800 hours in more buildings that other times of the day. It was also observed in the study region that the vulnerability of vehicle is above 0.6 in half of the road stretches during 0800 hours to 1000 hours and 1600 to 1800 hours due to high traffic density on the road section. From this study, we conclude that the vulnerability of an element at risk to landslide is a space and time event, and can be quantified using stochastic modeling. Therefore, the stochastic vulnerability modeling forms the basis for a quantitative landslide risk analysis and assessment.     

Organochlorine Pesticide Residues in Wheat and Drinking Water Samples from Jaipur, Rajasthan, India

The organochlorine pesticide contamination in dietary sources has caused serious threat to the human progeny. The present study was therefore conducted to evaluate the pesticide contamination in wheat flour and drinking water from Jaipur City, Rajasthan, India using Gas Chromatograph. All the wheat and water samples were found to be contaminated with various organochlorine pesticide residues of DDT and its metabolites, HCH and its isomers, heptachlor and its expoxide and aldrin. The amount of pesticide detected in wheat flour was higher than the permissible limits prescribed by WHO/FAO. In drinking water only a few pesticides exceeded the permissible limits. Seasonal variations of pesticides residues were also observed during the study period.     

Factors influencing the sinuosity of Pannagon River, Kottayam, Kerala, India: An assessment using remote sensing and GIS

The present study was carried out to identify the factors influencing the sinuosity of the Pannagon river, using the IRS P6 LISS III data and Geographical Information System (GIS) on 1:50,000 scale. The river follows meandering course and exhibits a narrow, highly sinuous and incised channel. Several lines of evidence including satellite and topographic data, geological maps and field investigations and the generated themes on lithology, structure, geomorphology, slope, riparian vegetation and hydrology have analyzed to understand the controls on the channel morphology of the Pannagon river. The average of sinuosity index of the selected reaches in the river on 1967 was 1.6 and of 2004 was 1.8. The sinuous patches are more in the lower reaches of the river and most of the area comes under floodplain with thick column of alluvial deposits. The analysis shown that the style and degree of sinuosity of the Pannagon river depends on a number of geological factors, including tectonics and the riparian vegetation also plays a major role.     

Evaluation of groundwater quality in and around Peenya industrial area of Bangalore, South India using GIS techniques

Groundwater resource forms a significant component of the urban water supply. Declining groundwater levels in Bangalore Urban District is generally due to continuous overexploitation during the last two decades or more. There is a tremendous increase in demand in the city for good quality groundwater resource. The present study monitors the groundwater quality using geographic information system (GIS) techniques for a part of Bangalore metropolis. Thematic maps for the study area are prepared by visual interpretation of SOI toposheets on 1:50,000 scale using MapInfo software. Physicochemical analysis data of the groundwater samples collected at predetermined locations form the attribute database for the study, based on which spatial distribution maps of major water quality parameters are prepared using MapInfo GIS software. Water quality index was then calculated by considering the following water quality parameters--pH, total dissolved solids, total hardness, calcium hardness, magnesium hardness, alkalinity, chloride, nitrate and sulphate to find the suitability of water for drinking purpose. The water quality index for these samples ranged from 49 to 502. The high value of water quality index reveals that most of the study area is highly contaminated due to excessive concentration of one or more water quality parameters and that the groundwater needs pretreatment before consumption.     

Heavy metal assessment using geochemical and statistical tools in the surface sediments of Vembanad Lake, Southwest Coast of India

The geochemical distribution and enrichment of ten heavy metals in the surface sediments of Vembanad Lake, southwest coast of India was evaluated. Sediment samples from 47 stations in the Lake were collected during dry and wet seasons in 2008 and examined for heavy metal content (Al, Fe, Mn, Cr, Zn, Ni, Pb, Cu, Co, Cd), organic carbon, and sediment texture. Statistically significant spatial variation was observed among all sediment variables, but negligible significant seasonal variation was observed. Correlation analysis showed that the metal content of sediments was mainly regulated by organic carbon, Fe oxy-hydroxides, and grain size. Principal component analysis was used to reduce the 14 sediment variables into three factors that reveal distinct origins or accumulation mechanisms controlling the chemical composition in the study area. Pollution intensity of the Vembanad Lake was measured using the enrichment factor and the pollution load index. Severe and moderately severe enrichment of Cd and Zn in the north estuary with minor enrichment of Pb and Cr were observed, which reflects the intensity of the anthropogenic inputs related to industrial discharge into this system. The results of pollution load index reveal that the sediment was heavily polluted in northern arm and moderately polluted in the extreme end and port region of the southern arm of the lake. A comparison with sediment quality guideline quotient was also made, indicating that there may be some ecotoxicological risk to benthic organisms in these sediments.     

Groundwater Pollution Around an Industrial Area in the Coastal Stretch of Maharashtra State, India

The main objective of this paper is to examine pollution threat, especially to the groundwater resources, around Tarapur industrial area (also called the Tarapur MIDC area) located on the Arabian Sea Coast in Thane District of Maharashtra State, India and suggest remedial measures that may also be relevant to other industrial areas on the Indian Sea Coast. One hundred and thirty one samples were collected from various sources, such as dugwells, borewells, dug-cum-borewells, effluent sumps, drainage channels (effluent channels), creeks and ocean, for chemical analyses. These analyses show that the area in general is characterized by hard water and high salinity hazard, possibly due to its proximity and hydraulic connection with the sea. Although the potability of groundwater is questionable in certain pockets, it is good enough for irrigation purposes at present. Low pH value and high heavy metal contents in the adjoining Muramba creek water is a matter of great concern and may be attributed to the indiscriminate disposal of industrial effluents to the drainage channels connecting the creek. Muramba Creek is well connected with the Arabian Sea, and there are evidences of seawater intrusion around this creek. Because of the fact that Muramba Creek is highly polluted, and is hydraulically connected with the dugwells and borewells surrounding the creek, it cannot be ruled out that the groundwater around this creek is susceptible to contamination. Unless measures are not taken immediately to stop the indiscriminate disposal of the solid wastes and liquid effluents in open ground and drainage channels, and measures are not taken to maintain the appropriate pH values at the effluent treatment facilities before their disposal, the problem would indeed be formidable one day, and it will be too late then for the authorities to take care of the resulting maladies. Few suggestions have been given for controlling and managing the industrial pollution around the Tarapur MIDC area. These suggestions are relevant to other industrial areas situated on the 7,000 km long Indian Sea Coast.     

Pesticide residue level in tea ecosystems of Hill and Dooars regions of West Bengal, India

In the present study we quantified the residues of organophosphorus (e.g. ethion and chlorpyrifos), organochlorine (e.g. heptachlor, dicofol, alpha-endosulfan, beta-endosulfan, endosulfan sulfate) and synthetic pyrethroid (e.g. cypermethrin and deltamethrin) pesticides in made tea, fresh tea leaves, soils and water bodies from selected tea gardens in the Dooars and Hill regions of West Bengal, India during April and November, 2006. The organophosphorus (OP) pesticide residues were detected in 100% substrate samples of made tea, fresh tea leaves and soil in the Dooars region. In the Hill region, 20% to 40% of the substrate samples contained residues of organophosphorus (OP) pesticides. The organochlorine (OC) pesticide residues were detected in 33% to 100% of the substrate samples, excluding the water bodies in the Dooars region and 0% to 40% in the Hill region. The estimated mean totals of studied pesticides were higher in fresh tea leaves than in made tea and soils. The synthetic pyrethroid (SP) pesticide residues could not be detected in the soils of both the regions and in the water bodies of the Dooars. Sixteen percent and 20% of the made tea samples exceeded the MRL level of chlorpyrifos in Dooars and Hill regions respectively. The residues of heptachlor exceeded the MRL in 33% (April) and 100% (November) in the Dooars and 40% (April) and 20% (November) in the Hill region. Based on the study it was revealed that the residues of banned items like heptachlor and chlorpyrifos in made tea may pose health hazards to the consumers.     

Pesticide Residues in Bovine Milk from a Predominantly Agricultural State of Haryana, India

One hundred forty seven samples of bovine milk were collected from 14 districts of Haryana, India during December 1998–February 1999 and analysed for the presence of organochlorine pesticide (OCPs) residues. ∑HCH, ∑DDT, ∑endosulfan and aldrin were detected in 100%, 97%, 43% and 12% samples and with mean values of 0.0292, 0.0367, 0.0022 and 0.0036 μg/ml, respectively. Eight percent samples exceeded the maximum residue limit (MRL) of 0.10 mg/kg as recommended by WHO for ∑HCH, 4% samples of 0.05 mg/kg for α-HCH, 5% samples of 0.01 mg/kg for γ-HCH, 26% samples of 0.02 mg/kg for β-HCH as recommended by PFAA and 24% samples of 0.05 mg/kg as recommended by FAO for ∑DDT. Concentrations of β-HCH and p,p′-DDE were more as compared to other isomers and metabolites of HCH and DDT.