INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 1, No1,2010

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1 GIS Study on Vulnerability Assessment of Water Quality in a Part of Cauvery River S.Hema 1, T.Subramani 2, L.Elango 3 1 Department of Civil Engineering, Kongu College of Engineering 2 Department of Civil Engineering Government College of Engineering 3 Department of Geology, Anna University shema_er@yahoo.com ABSTRACT Cauvery River is one of the significant sources of water supply for domestic, agricultural and industrial usage in Tamil Nadu. Inspite of large scale utilization of the river water, poor water management has resulted in large scale degradation of the quality of water. Hence a detailed study has been attempted in the Cauvery River between the latitudes ' 35.1" N & ' 24" N and the longitudes ' 40.7" E and ' 17.9" E. Four major tributaries such as Bhavani River, Noyal River, Amaravathi River and Thirumanimuthar River confluence with the Cauvery River in the study region. About fifty water samples were collected in the Cauvery River during February2009 and the samples were analyzed for the physical and chemical parameters such as ph, Electrical Conductivity, Total Dissolved Solids, alkalinity, hardness, Ca 2+, Mg 2+, Na +, K +, Cl 2 2, SO 4, CO 3, HCO 3 NO 3,and F. The analytical results were compared with the Indian (BIS) and International (WHO) standards to assess the suitability of water for drinking and the extent of deterioration. Spatial variations of various surface water quality parameters were studied using the Geographical Information System (GIS). The study indicates that some of the samples of February2009 exceed the permissible limit for drinking. The study further reveals that the variation of water quality with respect to space and time is not uniform. Agricultural runoff, sewage and industrial effluents are the probable sources for the variation of water quality in the study region. Key words: surface water pollution, Spatial variation, Industrial effluent 1. Introduction Today, due to scarcity of water, the competition for water resources is intense all over the world. Water pollution is relatively a new problem and increases the stress arising as a result of unprecedented population growth, urbanization, and industrialization since As the urbanization process continues, water pollution problems have become increasingly evident, and have led to serious ecological and environmental problems [1]. Industrial production without adequate regard for environmental impacts has increased water and air pollution, and has led to soil degradation and largescale global impacts such as acid rain, global warming, and ozone depletion. In most cities with water scarcity, urban and industrial wastes are generally disposed of without adequate treatment; 1

2 urban discharge of domestic sewage and industrial wastewater discharge are increasing, exacerbating foreseeable water shortages [7]. Only if we improve the use of water and water management we will meet the acute freshwater challenges that face us over the coming years. The scope of the present study and its main objective is to understand the surface water chemistry and water pollution along with the original direction of surface water and flow in the Cauvery basin. The protection of the water resources and treatment of water pollution are matters of urgent to permit ecologically sensitive construction and sustainable socioeconomic development in the whole catchment. To do so, it is first necessary to understand the mechanisms responsible for water pollution and the severity of the problem [3]. This study will allow environmental managers to develop a more reasonable policy for waste management and the prevention of water pollution based on joint efforts by local governments, enterprises, and farmers. 1.1 Study Area The Cauvery River starts in the Western Ghats and flows in eastwardly direction passing through the states of Karnataka, Tamil Nadu, Kerala and Pondicherry before it drains into Bay of Bengal. The total length of the river from the source to its outfall into Bay of Bengal is about 800 km. Of this, 320 km is in Karnataka, 416 km is in Tamil Nadu and 64 km length forms the common boundary between Karnataka and Tamil Nadu States. The Cauvery basin extends over an area of 81,155 km 2, which is nearly 24.7% of the total geographical area of the country. A detailed study has been attempted in the Cauvery River between the latitudes ' 35.1" N & ' 24" N and the longitudes ' 40.7" E and ' 17.9" E. Four major tributaries such as Bhavani River, Noyyal River, Amaravathi River and Thirumanimuthar River confluences with the Cauvery River in the stretch taken under study. The length of the river taken for the study is approximately 100 km. This study was conducted to characterize the water quality in the stretch of river Cauvery, which is one of the main sources of drinking water to Erode city, Bhavani, Karur and its surrounding areas. Many intakes are present on either banks of the river through which water is supplied for drinking for the local communities in the respective areas. So, this study will really help the researchers to understand the existing quality of the surface water in the rivers considered for study. The location of the stretch of the river Cauvery and its tributary rivers Bhavani, Noyyal, Amaravathy are shown in Figure01. 2

3 Figure01 Location map of the river stretches 3

4 2. Materials And Methods Surface water samples were collected from 50 locations during February 2009 along the course of the Cauvery River and its major tributaries namely Bhavani River, Noyyal River, Amaravathi River and Thirumanimuthar. The samples were collected in 1litre double cap polythene bottles. The samples were filtered through precleaned 0.45 µm acetate filters and were acidified with HNO 3 (1%) for the chemical analysis. The samples were analyzed for its ph, dissolved oxygen, alkalinity, hardness, turbidity, total dissolved solids, chloride, potassium, magnesium and trace elements like copper, arsenic, lead etc., with a view of finding out some hints on river water management [6]. Electrical Conductivity (EC) and ph were measured electromagnetically in the field using digital meters immediately after sampling. The samples were analysed for determining the concentrations of various chemical constituents such as, sodium, potassium, calcium, magnesium, chloride, bicarbonate, carbonate, sulphate, nitrate, fluoride and total dissolved solids (TDS) in the laboratory using the standard methods (Table1) as suggested by the American Public Health Association (APHA 1989 and1995) [2]. Ca 2+, Mg 2+, HCO 3, CO 3 2, Cl and TDS were analysed by volumetric titrations. Concentrations of Ca 2+ and Mg 2+ were estimated titrimetrically using 0.05N EDTA. Concentrations of HCO 3 and CO 3 2 were determined using 0.01N H 2 SO 4. Cl was estimated using 0.05N AgNO 3. Na + and K + ions were measured using flame photometer. SO 4 2, NO 3 and F were determined by spectrophotometric techniques. The accuracy of the chemical analysis was verified by calculating ionbalance errors and the errors were generally found to be around 10%. Table 01 Methods used for chemical analysis of groundwater Chemical parameters Methods Ca 2+ and Mg 2+ Titration using 0.05 N EDTA Na + and K + Flame Photometer 2 HCO 3 and CO 3 Titration using 0.01 N H 2 SO 4 Cl Titration using 0.05 N AgNO 3 NO 3 Spectrophotometer 2 SO 4 Spectrophotometer SiO 2 Spectrophotometer F Spectrophotometer B Atomic Absorption Spectrophotometer The study area forms part of the catchments of Cauvery River, which is one of the main sources of drinking water to Erode city as mentioned earlier. The industrial effluents contain appreciable amounts of inorganic and organic chemicals besides their byproducts. Most of the industries are small to mediumscale sectors and do not have any sewer lines. Many of them do not have proper wastewater treatment plants and they discharge industrial effluents in unlined channels/streams, thereby causing contamination of air, water and soil [5]. As a result, the highly coloured and toxic chemical effluents join river Cauvery, polluting the surface water and the groundwater. The area consists of variety of industries like tanneries, textile factories, dyeing industries, printing industries, bleaching units, etc., The Cauvery stretch in Erode region receives untreated sewage from the areas located in left and right banks. In the stretch of Cauvery taken for study, river Bhavani is one of the main tributary and joins Cauvery before it reaches Erode city as stated earlier. River Bhavani is also receiving the sewage and industrial effluents generated by the areas located around it. The next tributary through which the Cauvery River receives water is 4

5 river Noyyal, which has International attention for its polluted state because of the discharge of wastewater from the textile city of Tirupur. River Amaravathy, which runs through the Karur town, is the next major tributary for river Cauvery in which around seven samples were collected for analysis along its flow. On the left bank of the Cauvery, another tributary Thirumanimuthar joins and flows into it. This river stream is found to be dry most of the days in a year and receives flow only when there is rainfall in the nearly Sherveroys hill region. During the time of study, there was no flow in this tributary of river Cauvery. Collection of Toposheets of the river stretch Selection of Study Area in the river stretch Selection of sampling points along the river stretch Collection of samples & Analysis Comparison with the quality standards Figure 02 Methodology of the study 3. Results and Discussion Surface water samples were collected from 50 locations along the Cauvery river stretch within the study area including its four tributaries namely Bhavani River, Noyyal River, Amaravathi River and Thirumanimuthar. All the samples are found to have the parameters with in the permissible limits in the river Cauvery. Na + is exceeding the permissible limits at two locations in the Cauvery. Similarly, Na + concentrations are also found to exceed the permissible limits at two locations in Amaravathy River. In Noyyal, all the samples are found to exceed the permissible concentrations for Na +, and this may be due to the huge volume of industrial effluents being discharged into the Noyyal River from the Tirupur region. 5

6 Generally all the samples are moderately alkaline with ph ranging from 7.1 to 8.7. Ca, Mg, Cl and SO 4 are present in very low concentrations (less than 100 and 150 mg/l respectively), except in Noyyal river where the chloride concentration is found to vary between 1333 mg/l to 1560 mg/l in all the four locations. Noyyal River showed high TDS levels varying from 3210 to 3615 mg /l. The details of the samples exceeding the permissible limits prescribed by World Health Organisation (WHO) are shown in Table Surface Water Chemistry Cauvery River The ph in the Cauvery river stretch is found to vary between 7.1 and 8.5. The water samples are found to be alkaline in nature along the river stretch (figure03). The EC values are found to vary from 310 µmhos/cm to 1940 µmhos/cm in the Cauvery. The TDS varies in the range of 208 mg/l to 1324 mg/l. Nitrate content in the river stretch is found to vary from 1 mg/l to 45 mg/l which falls within the permissible limits of WHO (Table02). The average value of nitrate along the Cauvery river stretch is being 7.3. The Na + ions are varying between 28 mg/l to 357 mg/l exceeding the permissible limits at some places, which have an average value of 76.9 mg/l. The Na + ions play a vital role in water used for irrigation purposes. The K + ion is varying between 3 mg/l and 21 mg/l with an average value of 5.4 mg/l. Similarly, Cl contents in the river water samples are found to fall between 25 mg/l and 397 mg/l. The values do not exceed the allowable limits prescribed by WHO. The major ions are in the order Na + >Ca 2+ >Mg 2+ >K + = HCO 3 >Cl >SO 4 2 >NO 3 >CO 3 2 in Cauvery river (Table03). The variation of the ph, EC, TDS, Total Hardness, Alkalinity and fluoride along the river Cauvery is shown in figure 03 and figure 04 respectively. The values of EC, TDS and fluoride along the river course is found to increase which may be because of the discharge of wastewater in the river from the tanneries and textiles in and around the Erode region values ph Fluorides in mg/l Figure 03 Variations of Fluoride and ph in Cauvery River 6

7 values sampling locations TDS EC in micromho/cm TH in Mg/l Total Alkalinity in mg/l Figure 04 Variations of Alkalinity, EC, TDS and TH in Cauvery River mg/l Calcium Magnesium Sodium Potassium Chlorides Sulphates BiCarbonates Figure 05 Variations of Major ions in river stretch Bhavani River The ph in Bhavani River is between 7.0 and 7.2 with an average value being 7.0. The ph values show that the samples are very near to the neutral (figure06). The EC varies from 270 µmhos/cm to 330 µmhos/cm with an average of µmhos/cm. The TDS values fall between 165 mg/l and 216 mg/l (figure07)and has an average value of mg/l. All the samples in the Bhavani River is found to be within the permissible limits as per WHO for drinking (Table02). The Na + ion value in the collected water samples are varying from 12 mg/l to 35 mg/l in the river 7

8 stretch with an average value of 27 mg/l. Ca + ions ranges from 22 mg/l to 26 mg/l and has an average value of 23.2 mg/l. The Mg + values are found to be within the permissible limits along the river course taken for study (figure08). The values are found to vary between 11 mg/l to 19 mg/l and has an average value of 15 mg/l. K + varies between 2 mg/l and 3 mg/l along the river stretch with an average of 2.8 mg/l. The mean F content for the samples taken is 0.3 mg/l and the values vary from 0.2 mg/l to 0.4 mg/l. the major ions in the samples taken from Bhavani river are in the order of Na + >Ca 2+ >Mg 2+ >K + = HCO 3 >Cl >SO 4 2 >NO 3 >CO 3 2 (Table03). The Cl, F, SO 4 2 and NO 3 are found to be with in the permissible limits for drinking with average values of 23.2 mg/l, 0.3 mg/l, 16.4 mg/l and 4.2 mg/l respectively. Values B1 B2 B3 B4 B5 Fluorides in mg/l ph Figure 06 Variations of Fluoride and ph in Bhavani River mg/l B1 B2 B3 B4 B5 TDS in mg/l TH in mg/l EC in micromho/cm Total Alkalinity in mg/l 8

9 Figure 07 Variations of Alkalinity, EC, TDS and TH in Bhavani River mg/l B1 B2 B3 B4 B5 Calcium Magnesium Sodium Potassium Chlorides Sulphates BiCarbonates Figure 08 Variation of Major ions in Bhavani River Noyyal River The ph values in the samples of the Noyyal river stretch varies from 8.6 to 8.7 which is more alkaline in nature than the water samples taken from river Cauvery. Also, the F values are with in the permissible limit but the values are high compared to other tributaries of river Cauvery. (figure09). The average ph value being 8.7, which is very high compared to the other tributaries of Cauvery. The EC values ranges from 5170 µmhos/cm to 5830 µmhos/cm with an average value of 5562 µmhos/cm, which is very high in comparison to the other river water samples. This shows high degree of pollution in river Noyyal due to the wastewater being discharged in to it. The TDS varies between 3210 mg/l and 3675 mg/l with a mean value of mg/l, which is also found to be very high compared to the other river water samples (figure10). The NO 3 in Noyyal River ranges from 8 mg/l to 12 mg/l and has an average of 10 mg/l. But these values along the river stretch falls with in the permissible limits for drinking as per WHO standards (Table 02). The Cl, TH, Na + and TDS values are found to exceed the permissible limits as per WHO standards and are found to have the average values as mg/l, mg/l, mg/l and mg/l respectively. All these parameters play an important role in making use of the water for various purposes. Table02 shows the samples increasing the permissible levels as per WHO standards. The calcium ions are found to vary between 72 mg/l to 88 mg/l and have a mean value of 82 mg/l (figure11). From the results of 9

10 analysis of Noyyal river samples, it can be seen that the river water is highly polluted compared to other tributaries of Cauvery. So, when this water stream joins Cauvery, then it induces considerable amount of pollution to the main river, particularly when the discharge in the main river reduces. The major ions are in the order of Na + >Mg 2+ >Ca 2+ >K + = Cl >HCO 3 > SO 4 2 > CO 3 2 >NO 3 (Table03) Values N1 N2 N3 N4 Fluorides in mg/l ph Figure 09 Variation of Fluoride and ph in Noyyal River mg/l N1 N2 N3 N4 TDS in mg/l TH in mg/l EC in micromho/cm Total Alkalinity in mg/l Figure 10 Variations of Alkalinity, EC, TDS and TH in Noyyal River 10

11 mg/l N1 N2 N3 N4 Calcium Magnesium Sodium Potassium Chlorides Sulphates Carbonates BiCarbonates Figure 11 Variation of Major ions in Noyyal River Amaravathy River Amaravathy is also one of the main tributaries of river Cauvery, and it runs through Karur town. The ph in the river stretch is found to vary between 7.7 and 8.3 with an average value of 8.0 (figure12). The ph indicates that the water is alkaline in nature. The fluoride values are within the permissible limits except for one sample. This is shown in Table02. The EC varies from 710 µmhos/cm to 1660 µmhos/cm and has an average value of 1122 µmhos/cm (figure13). The TDS values are found to be within the permissible limits as per the WHO standards and the values are shown in Table02. The average value of TDS being mg/l, this has a maximum value of 943 mg/l. The NO 3 values are within the allowable limits for drinking and have an average value of 2 mg/l along the river course. The Na + ions have the maximum value of 242 mg/l and minimum value of 92 mg/l with a mean value of 158 mg/l which exceeds the permissible limit at two locations along the river (Table 02). The Ca 2+ ions do not exceed the permissible limits prescribed as per WHO standards at any location. The average value of the Ca 2+ is 34 mg/l. The K + values falls between 6 mg/l and 16 mg/l with an average of 10.2 mg/l. The Cl ion has a maximum value of 337 mg/l and a minimum value of 85 mg/l. It is also within the allowable limit (figure14). The Major ions are in the order of Na + >Mg 2+ >Ca 2+ >K + = HCO 3 >Cl >SO 4 2 > CO 3 2 >NO 3 (Table 03) 11

12 Values A1 A2 A3 A4 A5 Fluorides in mg/l ph Figure 12 Variation of Fluoride and ph in Amaravathy River mg/l A1 A2 A3 A4 A5 TDS in mg/l TH in mg/l EC in micromho/cm Total Alkalinity in mg/l Figure 13 Variations of Alkalinity, EC, TDS and TH in Amaravathy River 12

13 mg/l A1 A2 A3 A4 A5 Calcium Magnesium Sodium Potassium Chlorides Sulphates Carbonates BiCarbonates Figure 14 Variation of Major ions in Amaravathy River 13

14 Parameters Table 02 Surface water samples of the study area exceeding the permissible limits prescribed by WHO for drinking purposes WHO international standard Most desirable limit Maximum allowable limit Samples exceeding permissible limits in Cauvery Samples exceeding permissible limits in Amaravathy Samples exceeding permissible limits in Noyyal During February 2009 Samples exceeding permissible limits in Bhavani Undesirable effect ph Nil Nil Nil Nil Taste Nil Nil 14,15,16,17 Nil Gastro intestinal TDS 500 1,500 irritation TH Nil Nil 14,15,16,17 Nil Scale Formation Na , 48 6,7 14,15,16,17 Nil Ca Nil Nil Nil Nil Scale Formation Mg Nil Nil Nil Nil Cl Nil Nil 14,15,16,17 Nil Salty taste NO 3 SO Nil Nil Nil Nil Blue Baby Nil Nil Nil Nil Laxative effect F 1.5 Nil 7 16 Nil Fluorosis 14

15 Table 03 Statistical values of surface water quality ph EC, umho/cm TDS, mg/l NO3, as N mg/l Phen, mg CaCO3/L Total, mg CaCO3/L Total, mg CaCO3/L Ca ++ mg CaCO3/L Cauvery River Stretch Maximum Minimum Mean Median Mode SD Amaravathy River Stretch Maximum Minimum Mean Median SD Noyyal River Stretch Maximum Minimum Mean Ca ++, mg/l Mg ++, mg/l Na +, mg/l K +, mg/l Cl, mg/l SO4 2, mg/l CO3, mg/l HCO3, mg/l F, mg/l 15

16 Median SD Bhavani River Stretch Maximum Minimum Mean Median SD

17 INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 1, No 1, 2010 Conference Paper Research Article 4. Conclusion The results obtained from the analysis of surface water quality along the Cauvery river stretch and its tributaries namely Bhavani River, Amaravathi River and Thirumanimuthar River suggest that the level of pollution is not beyond control as yet, but the condition may become worse due to cumulative discharge of untreated industrial effluents and pesticides in the near future [8]. From the present study, it can be concluded that the water quality of river Noyyal is under stress of severe pollution. The water is unfit for drinking as well as for domestic purposes. Therefore effective pollution control measures are a must to save natural water sources from further deterioration, very urgently. 5. References 1. Almasri.M.N, J.J.Kaluarachchi, Assessment and management of longterm nitrate pollution of ground water in agriculturedominated watersheds, Journal of Hydrology 295: APHA, Standard Methods for the Examination of Water and Wastewater, 18th ed. American Water Works Association and Water Pollution Control Federation. 3. Simeonov.V, J.A. Stratis, C. Samara, G. Zachariadis, D. Voutsa, A. Anthemidis, M. Sofoniou, T.H. Kouimtzis, Assessment of the surface water quality in Northern Greece, Water Research 37: Panda.U.C, S.K. Sundaray, P. Rath, B.B. Nayak, D. Bhatta, Application of factor and cluster analysis for characterization of river and estuarine water systems a case study: Mahanadi River (India), Journal of Hydrology 331 (34): Basin Subbasin Inventory of Water Pollution, 1989; The Krishna Basin. ADSORBS/21/ 8990, Published by Central Pollution Control Board, Delhi. 6. Tripathy, G. K., J.K. Parikh, Water Quality Monitoring Using GIS: Case Study of Krishna Basin, presented at Integrated Basin Management Seminar, CWRDM, Kerala on 1920 May, Sun.C, Y. Dong, S. Xu, S. Yao, J. Dai, S. Han, L. Wang, Trace analysis of dissolved polychlorinated organic compounds in the water of theyangtse River (Nanjing, China), Environ. Pollution. 117: Singh.K.P, A. Malik, D. Mohan, S. Sinha, Multivariate statistical techniques for the evaluation of spatial and temporal variations in water quality of Gomti River (India)a case study, Water Res. 38: WHO, Guidelines for drinking water health criteria and other supporting information, World Health Organization, Geneva, Vol. 2. This paper is presented at the International Conference on Disaster Mitigation and Management,

ASSESSMENT OF GROUNDWATER QUALITY USING WQI METHOD AROUND VELLALORE MUNICIPAL SOLIDWASTE DISPOSAL SITE IN COIMBATORE, TAMILNADU, INDIA

Int. J. Chem. Sci.: 14(1), 2016, 229-243 ISSN 0972-768X www.sadgurupublications.com ASSESSMENT OF GROUNDWATER QUALITY USING WQI METHOD AROUND VELLALORE MUNICIPAL SOLIDWASTE DISPOSAL SITE IN COIMBATORE,