INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 2, No 2, Copyright 2010 All rights reserved Integrated Publishing Association

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1 INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 2, No 2, 2011 Copyright 2010 All rights reserved Integrated Publishing Association Research article ISSN Assessment of ground water quality characteristics and Water Quality Index (WQI) of Bidar city and its Shivasharanappa 1, Padaki Srinivas 2, Mallikarjun S Huggi 3 1- Assistant. Professor, Dept of Civil Engineering, P. D. A. College of Engineering (Autonomous Institution) Gulbarga, Karnataka State, India 2- Professor & Head, Chemistry Dept., P. D. A. College of Engineering (Autonomous Institution) Gulbarga, Karnataka State, India 3- Lecturer, Civil Dept., G. N. D. College of Engineering, Bidar, Karnataka State, India shiva_patil11@rediffmail.com doi: /ijes ABSTRACT The present work is aimed at assessing the water quality index (WQI) for the ground water of Bidar city and its industrial area. The groundwater samples of all the 35 wards were collected and subjected for a comprehensive physicochemical analysis. For calculating the WQI, the following 17 parameters have been considered viz., ph, total hardness, calcium, magnesium, chloride, nitrate, sulphate, total dissolved solids, iron, fluoride, sodium, potassium, alkalinity, manganese, dissolved oxygen, total solids & zinc. The results analyzed (by WQI method) have been used to suggest models for predicting water quality. The analysis reveals that the groundwater quality status of the study area is excellent, but it also needs to be protected from the perils of future contamination by giving certain degree of treatment viz., disinfection. Keywords: Groundwater, Water quality standards, Water quality characteristics, Water quality index. 1. Introduction Groundwater is used for domestic, industrial, water supply and irrigation all over the world. In the last few decades, there has been a tremendous increase in the demand for fresh water due to rapid growth of population and the accelerated pace of industrialization. Human health is threatened by unsanitary conditions through open drain carrying and disposing waste water into natural water bodies. Rapid urbanization, especially in developing countries like India, has affected the availability and quality of groundwater due to its overexploitation and improper waste disposal, especially in urban areas. According to WHO organization, about 80% of all the diseases in human beings are caused by water 8. Once the groundwater is contaminated, its quality cannot be restored back easily and to device ways and means to protect it. 1-3 Water quality index is one of the most effective tools to communicate information on the quality of water to the concerned citizens and policy makers. It, thus, becomes an important parameter for the assessment and management of groundwater. WQI is defined as a rating, reflecting the composite influence of different water quality parameters. WQI is calculated from the point of view of the suitability of groundwater for human consumption. The objective of the present work is to discuss the suitability of groundwater for human consumption based on computed, groundwater characteristics, quality assessment and water quality index values. Received on October 2011 Published on November

2 2. Materials and Method The study area Bidar City, the head quarters of the Bidar district of Karnataka State, India, is located in the northern most part of the state of Karnataka on Deccan plateau (Figure No. 1). The city including its industrial area is divided into 35 wards. It is situated at a distance of 669 Kms. from the state capital Bangalore and at a distance of 141 Kms from Hyderabad. Bidar City and the ancient monuments that exist today belong to the period of Bahumani Kings in the fifteenth century. The important monumental works in Bidar are, the Kings Fort with the old palace and other ancient monuments inside it, Madarasa Mohammad Gawan (Oldest International University), Tombs of BARID SHAHI Kings, Dargah of Hazarath Khaja Abdul Fiaz, Tomb of Ali Barid and Tomb of Hazarath Ziauddin Sahib. Apart from the above monuments, the other places of Historical and Pilgrimage are Papanasham Shiva Temple, Guru Nanak Zhira Gurudwara and Narasimha Swamy Temple and Zheera. Bidar can be located at north latitude and east longitude and its elevation is about 664 m above the mean sea level. The climate of Bidar and its environs is reported to be pleasant and is relatively cooler when compared to the temperatures in the neighboring districts of Karnataka. The average annual rainfall as recorded in the previous years is mm, mm; the monsoon period is over four months i.e. between June to September. The highest recorded during the above period is mm during July month. The average maximum temperature of 43 C is recorded during the period is in the month of May. The maximum temperature however varies from 39 C to 43 C during the month of February to June and falls to 18 C during November month. The mean annual maximum humidity observed in the morning was pc and the minimum was observed in the evening was 43.7 pc. Humidity will be least during the month of May. During summer the predominant wind direction is westerly and during the monsoon seasons wind blows in Southwesterly directions. During the winter seasons, the predominant wind direction is Southeasterly. Bidar city is on the plateau being almost on its northern edge, which gives a picturesque view of the low-lying lands on the North and East. The plateau is of irregular shape, land stretching about 35.4 Km in length and 19.3 Km in width. The plateau consists of red laterite rocky crust, of a depth varying from 30.5 m to m supported on impervious trap base. This has resulted in springs at the cleavages between trap and laterite rocks. Such water springs can be observed in Bidar at Gurunanak Zheera, Narasimha Zheera, Papanasha Shiva Temple and a few other places. The land in Bidar and its environs drains into Manjra River (which flows in the region) is a tributary of Godavari River. The major soil types are, Red laterite soil, Black cotton soil and a combination of the above two types. The commonly used building materials (laterite stones) can be easily cut from laterite soil. Once they are cut and exposed to the atmosphere, it gets harder. Some parts of the district have black cotton soil, which is good for agricultural purposes. Samples were collected from all the 35 wards as per standard procedural method for the physicochemical analysis of 17 parameters, 4 it has been revealed that all the parameters studied under the area are within the prescribed limits

3 Figure 1: Location of Bidar City Figure 1: Bidar City Map 967

4 Chloride, Total Solids, Total Dissolved Solids, mg/l Total Hardness, Calcium Hardness, Magnessium Hardness, mg/l 3. Results and Discussions In this chapter for the purpose of revealing the water quality of 35 bore wells of 35 wards covering the study area have been established by determining the physical and chemical characteristics as per standard methods 4. They have been listed systematically and represented in table-2. The parameters viz., ph, total dissolved solids and total solids know the physical characteristics of the ground water under the study area. The chemical characteristics of the ground water under the study area are known by the parameters viz., total hardness, calcium hardness, magnesium hardness, iron, fluoride, nitrate, chloride, sulfate, sodium, potassium, alkalinity, manganese, zinc, and dissolved oxygen. Total Hardness, Calcium Hardness & Magnesium Hardness variations during the study period is presented in Figure Sampling Points TH mg/l Ca mg/l Mg mg/l Figure 2: TH - Total Hardness, Ca - Calcium Hardness and Mg - Magnesium Hardness variations during the study period Chloride, TS & TDS variations during the study period are presented in Figure Sampling Points Cl mg/l TS mg/l TDS mg/l Figure 3: Cl - Chloride, TS - Total Solids, and TDS - Total Dissolved Solids variations during the study period Iron, Fluoride & Manganese variations during the study period are presented in Figure 4 968

5 ph, Zinc, Dissolved Oxygen, mg/l Sulfate, Sodium, Pottasium, mg/l Iron, Fluoride, Manganese, mg/l Fe mg/l F mg/l Mn mg/l Sampling Points Figure 4: Fe - Iron, F - Fluoride, and Mn - Manganese variations during the study period Sulfate, Sodium & Potassium variations during the study period are presented in Figure SO4 mg/l Na mg/l K mg/l Sampling Points Figure 5: SO 4 - Sulfate, Na - Sodium, and K - Potassium variations during the study period ph, Zinc & DO variations during the study period is presented in Figure Sampling Points ph Zn mg/l DO mg/l Figure 6: ph Hydrogen Ion Concentration, Zn - Zinc, and DO Dissolved Oxygen variations during the study period Alkalinity & Nitrate variations during the study period are presented in Figure

6 Alkalinity, Nitrate, mg/l sampling points Alkalinity mg/l NO3 mg/l Figure No. 7: Alkalinity and NO 3 - Nitrate, variations during the study period The physicochemical analysis of the ground water and the percent compliance with the Indian Standards and WHO are summarized in table 1. 8,7 Table 1: Comparison of groundwater quality with drinking water standards, Indian and WHO Parameters Indian Standard Percent Compliance WHO Standard Percent Compliance ph TH, mg/l Ca, mg/l Mg mg/l Cl, mg/l TDS, mg/l Fe, mg/l F, mg/l NO 3, mg/l SO 4, mg/l Na, mg/l K, mg/l Alkalinity mg/l Mn, mg/l Zn, mg/l Table 2: Groundwater physico-chemical characteristics of Bidar City & its industrial area Parameters Sampling point No. (Ward No.) ph TH Ca Mg Cl TDS Fe

7 F NO SO Na K Alkalinity Mn Zn DO TS Table 2: continued. Parameters Sampling point No. (Ward No.) ph TH Ca Mg Cl TDS Fe F NO SO Na K Alkalinity Mn Zn DO TS Table 2: continued. Parameters Sampling point No. (Ward No.) ph TH Ca Mg Cl TDS Fe F NO SO Na K Alkalinity Mn Zn DO

8 TS Table 2: continued. Parameters Sampling point No. (Ward No.) Statistical values for all the 35 sampling points Mean S.D C.V Min. Max. ph TH Ca Mg Cl TDS Fe F NO SO Na K Alkalinity Mn Zn DO TS TDS Total dissolved solids in mg/l, TH Total Hardness in mg/l, Ca Calcium Hardness in mg/l, Mg Magnesium Hardness in mg/l, Fe Iron in mg/l, F Fluoride in mg/l, NO 3 Nitrate in mg/l, Cl Chloride in mg/l, SO 4 Sulphate in mg/l, K Potassium in mg/l, Mn Manganese in mg/l, Zn Zinc in mg/l, DO Dissolved Solids in mg/l, TS Total solids in mg/l, S.D Standard deviation, C.V Co-efficient of variation %, Min. Minimum, Max. - Maximum. Water Quality Index 7 For computing water quality index three steps are followed as given in table-3. In the first step, each of the 15 parameters has been assigned a weight (wi) according to its relative importance in the over all quality of water for drinking purposes. The maximum weight of 5 has been assigned to the parameter nitrate due to its major importance in water quality assessment. Magnesium which is given weight of 2 as magnesium by it self may not be that harmful 4 Second step, relative weight (Wi) is computed from the following equation: wi W i = (1) n wi i 1 Where (Wi) is the relative weight, (wi) is the weight of each parameter and n is the number of parameters. Calculated relative weight (wi) values of each parameters are also given in (table 3). 972

9 In the third step, a quality rating scale (qi) for each parameter is assigned by dividing its concentration in each water sample by its respective standard according to the guidelines laid down in the BIS and the result is multiplied by 100: q i = ( C i / S i ) * (2) Where qi is the quality rating, Ci is the concentration of each chemical parameter in each water sample in mg/l, and Si is the BIS (Bureau of Indian standards) water standard for each chemical parameter in mg/l according to the guidelines of the BIS For computing the WQI, the SIi is first determined for each chemical parameter, which is then used to determine the WQI as per the following equation SI i = Wi * qi (3) WQI = SI i (4) SI i is the sub index of Ith parameter, q i is the rating based on concentration of ith parameter and n is the number of parameter. The computed WQI values are classified into five types excellent water, good water, poor water very poor water and water unsuitable for drinking as shown in table no. 4 Table 3: Relative weight of chemical parameters. 7 Sl. Nos. Chemical Parameters Indian Standards Weightage (w i ) Relative Weight (W i ) Quality Rating (qi) Sub Index (SI i ) 1 ph TH Ca Mg Cl TDS F NO Fe SO Na K Alkalinity Mn Zn eg: For ph, W i = i 1 wi = 51 W i = qi = SIi = wi = 4/51 = , qi = ( C n i / S i ) * 100 = ( / 8.5 ) * 100 = 88.65, wi Si = Wi * qi = * =

10 7, 10 Table 4: Water quality classification based on WQI value WQI Value Water Quality <50 Excellent Good water Poor water Very poor water >300 Water unsuitable for drinking WATER QUALITY INDEX (WQI) The three steps of water quality index are: Step 1 wi = according to the relative importance (overall quality of water for drinking purpose). The maximum weightage of 5 has been assigned to the parameter nitrate and minimum weightage of 2 has been assigned for manganese (may not be that harmful). Step 2 Relative weight (Wi) W i = i 1 wi n wi Si = Wi * qi qi = ( C i / S i ) * 100 Where qi = Quality rating, Ci = concentration of each chemical parameter in each water sample in mg/l, Si = Indian drinking water standard for each chemical parameter in mg/l. (according to BIS10500: 1991) Water quality index (WQI) = sub index of the I th parameter. Step 3 WQI = SI i = Conclusions After the careful study of analysis, interpretation and discussions of the numerical data following conclusions have been drawn for the ground water of Bidar city. The groundwater is crystal clear, odorless, and palatable. Most of the bore wells yield potable water with moderate mineral or dissolved salts. Water is soft in almost all the sampling points. As there is no considerable increase in chloride and sulphate, it shows that there is no possible contamination of groundwater due to percolation of polluted surface water. The concentration of nitrate and fluoride in the entire Bidar City is well within the permissible limit. Though the geological strata of Bidar City consists of laterite stones, which is rich in iron but it seems iron is in slightly dissolvable state, hence iron also detected well within the permissible limit 974

11 as per Indian standards. But as per WHO Standards iron in ground water is slightly high. Whatever the hardness is reported, it is by calcium itself, which is also little higher than the permissible limits. Scaling of utensils, household boilers have been reported by survey. It has been revealed by the analysis that industrial effluents have negative effect on the quality of ground water of Bidar City and its industrial area. The water quality index (WQI) falls in the Excellent Range and hence the ground water of Bidar city is as considered as Excellent. The analysis reveals that the groundwater of the area, needs certain degree of treatment before consumption (at least disinfection), and it also needs to be protected from the perils of contamination. Acknowledgement Thanks to Hyderabad Karnataka Education Society Gulbarga, Karnataka State, India 5. References 1. M.A. Maniyar (1990), Evaluation of Groundwater Quality of the Bore wells of Gulbarga city maintained by K.U.W.S. and D. Board. M.E. Environmental Engineering Dissertation Submitted to Gulbarga University Gulbarga, pp S.R. Mise (1988), Wastewater Characterization of Gulbarga City (Zones A & B ) M.E., Environmental Engineering Dissertation Work Submitted to Gulbarga University Gulbarga, pp Shivasharanappa (1988), wastewater Characterization of Gulbarga City (Zone C ). M.E., Environmental Dissertation Work Submitted to Gulbarga Univesity Gulbarga, pp APHA, American Public Health Association (2003), standard method for examination of water & wastewater specifications, Washington DC, 6, 19th Edition. 5. Bureau of Indian Standards, 1993, (IS 10500:1991), Edition WHO (World Health Organization) Guidelines for drinking water quality (1993), second edition, Vol. 1, C.R. Ramakrishniah, C.Sadashivam & G.Ranganna (2009), Assessment of Water Quality Index for the Groundwater in Tumkur, Karnataka State, India E- Journal of Chemistry, 6(2), pp Nirdosh Patil, Atiq Ahmed, Sureshbabu H, N M Kottureshwar, M. Jayashree, J.Nijalingappa (2010), Study on the Physico-Chemical characteristics of ground water of Gulbarga City (Karnataka) International Journal of Applied Biology & Pharmaceutical Technology, 1(2), Aug-Oct, Divya Rani Thomas, B. Sunil, C. Latha (2011), Assessment of seasonal variation on Physicochemical & Microbiological quality of drinking water at Mannuthy, Kerala,International Journal of Chemistry, Environmental 7 Pharmaceutical research, 2(2-3), May Dec, p

12 10. Kavita Parmar, Vineeta Parmar (2010), Evaluation Water quality Index for drinking purpose of river Subenarekha in Singhbhum District, International Journal of Environmental Sciences, 1(1), pp