WQI Based Studies on Groundwater Quality at Andhra University Campus, Visakhapatnam

IJSTE - International Journal of Science Technology & Engineering | Volume 3 | Issue 09 | March 2017 ISSN (online): 2349-784X

WQI Based Studies on Groundwater Quality at Andhra University Campus, Visakhapatnam Dr. G. V. R. Srinivasa Rao Professor Department of Civil Engineering Andhra University, Visakhapatnam

Dr. Y. Abbulu Professor Department of Civil Engineering Andhra University, Visakhapatnam

T. P. Sreejani Junior Research Fellow Department of Civil Engineering Andhra University, Visakhapatnam

Abstract In this present work, Water Quality Index (WQI) based study on Groundwater quality at Andhra University Campus, Visakhapatnam is aimed at to evaluate its suitability for drinking purpose. Groundwater samples are collected from the twenty five bore wells during the Post-monsoon (November 2015 to February 2016), Pre-monsoon (March 2016 to June 2016) and Monsoon (July 2016 to October2016) periods at regular intervals of time and are analysed for various physico-chemical parameters using standard laboratory procedures. The Water quality Indices (WQI) calculated both in National Sanitation Foundation Water Quality Index (NSFWQI) and Weighted Arithmetic Index Water Quality Index (WAIWQI) methods indicated that the quality of groundwater is found to be good with respect to physico-chemical parameters in all seasons in the study area and suitable for drinking purpose.

Keywords: Monsoon, Pre-Monsoon, Post-Monsoon, WQI, NSFWQI and WAIWQI ________________________________________________________________________________________________________ I.

INTRODUCTION

Water is the valuable and crucial resource for sustenance of life and also for any developmental activity. Groundwater is an important source of water supply throughout the world. However, in the recent past groundwater quality is getting deteriorated due to various reasons and making it unsuitable for drinking purposes. Hence, it became necessary to assess the groundwater quality spatially over sufficient periods of time to arrive at its suitability for various purposes.

Water quality indices are aggregation and communication tools for monitoring water quality. These indices have been developed to summarize water quality data in an easily expressible and understandable format with less information than the raw data. WQI indicates the quality of water in terms of a index number which represents overall quality of water for any proposed use.

The WQI improves the comprehension of general water quality issues presents the spatial and temporal water quality information and illustrates the need for effectiveness of protective practices.(Curtis G.Cude, 2001). The temporal variations in the quality of groundwater due to external inputs can also be traced out using WQI and has been established in the study conducted by (Prashant N. Rajankar et.al, 2011) in the Bhandara district, Maharastra. The source of pollution to deteriorate the groundwter quality whether it is point or area can be suggested by visualizing the WQI distributions using GIS software. One such study conducted by A. Gibrilla et.al, (2011), at Densu river basijn of Ghana has shown an increase in anthropogenic contributions to pollution in the study areas. From the study based on WQI conducted by Rupal (2012) in Surat city, India, it is observed that there are higher values of Iron, TDS, Hardness, Chloride and Manganese in groundwater and it needs to be protected from the perils of contamination.

A study conducted by Sanjib Das (2013) in and around Kolkata has shown that 66% of Groundwater samples are not fit for drinking due to high contents of Chlorides & Hardness. Similarly, the WQI studies have shown that the groundwater is unfit for drinking in major portions of the Dwarka district, in Delhi. (Ravi Kant Dubey, 2014). The modified water quality indices along with their sub-indices to assess the quality of groundwater in urban areas which describe the overall water quality more reliably.

(Mohammad Reza Mohebbia et.al, 2013). Additional inputs like entropy weights make WQI perfect resulting in more reasonable results. This has been demonstrated in the study on Groundwater quality using WQI by Li Pei-Yue et.al (2010) in the study area, Pengyang County, North West China.

II. STUDY AREA The study area, Andhra University is located in Visakhapatnam, Andhra Pradesh. It lies between latitude 17º43’5.38’’N and longitude 83º19’17.61’’E with an area of 422 acres and a varying elevation from 10MSL to 62.5 MSL. The average annual

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WQI Based Studies on Groundwater Quality at Andhra University Campus, Visakhapatnam (IJSTE/ Volume 3 / Issue 09 / 044)

rainfall is 955mmand the mean annual temperature and humidity are23.7ºC and 67 to 78% respectively. It is divided into two campuses viz., South campus and North campus.

III. METHODOLOGY Collection and Analysis of water samples Groundwater samples are collected from the 25 bore wells that exist in the study area during the period November 2015 to October 2016. They are analysed for various physico-chemical parameters such as pH, Electrical conductivity (EC), Total Dissolved Solids (TDS), Total alkalinity (TA), Total hardness (TH), Sulphates (SO42-), Chlorides (Cl-), Iron (Fe), Calcium (Ca), Magnesium (Mg), Sodium(Na), Potassium (K) and Fluorides(F) in standard procedures as per American Public Health Association (APHA 1995).

Calculation of Water quality indices The results from the laboratory analysis are then used to obtain Water Quality Indices (WQI)in both Weighted Arithmetic Water Quality Index (WAIWQI) and National Sanitation Foundation Water Quality Index (NSFWQI).

WAIWQI which ranges from 0 to 100 and above representing Excellent to Unsuitable for usage is calculated as given below.

WQI =∑QiWi/∑Wi (1) The quality rating scale (Qi) for each parameter is calculated by using the following equation Qi = 100*{(Vi- Vo) / (Si-Vo)} (2) Where, Vi =estimated concentration of ith parameter in the analysed water Vo =The ideal value of pure water Si =Standard value of ith parameter The unit weight (Wi) for each water quality parameter is calculated by using the formula Wi =K/ Si (3) Where, K = proportionality constant =1/∑(1/Si ) NSFWQI which ranges from 0 to 100 representing poor to excellent quality is calculated as given below.

WQI= ∑SIi (4) Where SIi= wi×qi (5) SIi = sub-index of ith parameter wi= relative weight and is calculated as wi=1/si si= standard values of parameters qi = quality rating of ith parameter ci = experimental value IV. RESULTS AND DISCUSSIONS Following are the minimum and maximum values of various parameters analysed during the Post-monsoon(Nov2015 to Feb 2016), Pre-monsoon(March 2016 to June 2016) and Monsoon (July2016 to October 2016) seasons. pH and Electrical Conductivity (EC) The pH of the samples was found to be varying from a minimum value of 6.012 to a maximum value of 7.99 in the postmonsoon, minimum value of 6.01 to a maximum value of 8.62 in the pre-monsoon and minimum value of 6.00 to a maximum value of 8.02 in the monsoon. The EC values were in the range of 0.01 to 20.22, 0.10 to 874.80 and 0.10 to 2.90 in the postmonsoon, pre-monsoon and monsoon respectively.

Calcium (Ca+2) and Magnesium (Mg+2) Calcium (Ca+2) concentrations vary between 78 to 226mg/l, 62 to 380mg/l and 66 to 190mg/l in post-monsoon, pre-monsoon and monsoon respectively. Magnesium (Mg+2) concentrations vary between 18 to 238mg/l, 10 to 308mg/l and 12 to 358 mg/l in postmonsoon, pre-monsoon and monsoon respectively.

Sodium (Na+) and Potassium (K+) Sodium (Na+) concentrations vary between 10.5 to 97.2mg/l, 6.8 to 99 mg/l and 1.2 to 98.1 mg/l in post-monsoon, pre-monsoon and monsoon respectively. Potassium (K+) concentrations vary between 4.3 to 30mg/l, 4.2 to 28.3mg/l and 5.7 to 29.9mg/l in post-monsoon, pre-monsoon and monsoon respectively.

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WQI Based Studies on Groundwater Quality at Andhra University Campus, Visakhapatnam (IJSTE/ Volume 3 / Issue 09 / 044)

Bicarbonate (HCO3-) and Carbonate (CO3-) Bicarbonate (HCO3-) concentrations varied from 170 to 690mg/l, 5 to 690mg/l and 5 to 515mg/l in post-monsoon, pre-monsoon and monsoon respectively. Carbonate (CO3-) concentrations varied from 20 to 170mg/l, 30 to 240mg/l and 10 to 210 mg/l in post-monsoon, pre-monsoon and monsoon respectively.

Chlorides (Cl-) and Sulphates (SO4-2) Chlorides (Cl-) concentrations vary between 91.97 to 219.93mg/l, 79.97 to 337.4mg/l and 37.99 to 213.93mg/l in post-monsoon, pre-monsoon and monsoon respectively. Sulphates (SO 4-2) concentrations vary between 9.8 to 92.91mg/l,6.8 to 89.95mg/l and 1.5 to 92.92mg/l in post-monsoon, pre-monsoon and monsoon respectively.

Iron (Fe) Iron (Fe) concentrations vary between 0.01 to 0.05mg/l, 0.02 to 0.5 mg/l and 0.01 to 0.1mg/l in post-monsoon, pre-monsoon and monsoon respectively.

Fluoride (F) Fluoride (F) concentrations vary between 0.08 to 0.50mg/l,0.03 to 0.29mg/l and 0.04 to 0.48mg/l in post-monsoon, pre-monsoon and monsoon respectively.

Total dissolved solids (TDS) Total dissolved solids (TDS) concentrations vary between 300 to 1860mg/l,240 to 1940 mg/l and 200 to1860 mg/l in postmonsoon, pre-monsoon and monsoon respectively.

Total Alkalinity (TA) Total Alkalinity (TA) concentrations vary between 225 to 680mg/l, 15 to 740mg/l and 125 to 555mg/l in post-monsoon, premonsoon and monsoon respectively.

Total Hardness (TH) Total Hardness (TH) concentrations vary between 126 to 344mg/l, 110 to 448 mg/l and 116 to 450mg/l in post-monsoon, premonsoon and monsoon respectively.

Water quality indices On the basis of the WQI, the water quality index obtained for ground water samples in two different water quality indices are in the following tables Table – 1 Water quality rating as per WAIWQI (November 2015 to October 2016) SNo

Borewell numbers

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

NBW-1 NBW-2 NBW-3 NBW-4 NBW-5 NBW-6 NBW-7 NBW-8 NBW-9 NBW-10 NBW-11 NBW-12 SBW-1 SBW-2 SBW-3 SBW-4 SBW-5 SBW-6 SBW-7 SBW-8 SBW-9

WQIavg (Post- Monsoon) 34.40 32.02 25.60 34.95 30.25 32.71 32.71 32.21 23.54 29.68 21.93 34.39 35.11 36.37 29.11 34.64 22.88 32.30 23.89 36.50 39.22

Quality rating Good Good Good Good Good Good Good Good Excellent Good Excellent Good Good Good Good Good Excellent Good Excellent Good Good

WQIavg (Pre-Monsoon) 16.39 18.87 26.59 33.80 28.33 27.80 27.80 24.70 20.81 22.68 22.19 22.62 29.53 28.93 24.30 17.31 22.14 18.63 23.81 19.03 28.13

Quality rating

WQIavg (Monsoon)

Quality rating

Excellent Excellent Good Good Good Good Good Excellent Good Good Good Good Good Good Excellent Excellent Excellent Excellent Excellent Excellent Good

27.65 32.42 27.29 26.52 37.11 30.53 30.53 38.30 30.32 36.40 31.17 37.53 33.88 36.23 22.66 35.66 29.59 37.08 24.24 29.74 43.96

Good Good Good Good Good Good Good Good Good Good Good Good Good Good Excellent Good Good Good Excellent Good Good

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WQI Based Studies on Groundwater Quality at Andhra University Campus, Visakhapatnam (IJSTE/ Volume 3 / Issue 09 / 044)

22 23 24 25

SBW-10 SBW-11 SBW-12 SBW-13

26.32 30.43 25.29 24.60

Good Good Good Excellent

24.94 24.31 19.95 26.67

Excellent Excellent Excellent Good

29.32 36.95 25.00 31.60

Good Good Excellent Good

Fig. 1: Seasonal variations of WAIWQI in North campus, AU (November 2015 to October 2016)

Fig. 2: Seasonal variations of WAIWQI in South campus, AU (November 2015 to October 2016)

Table - 2 Water quality rating as per NSFWQI (December 2015 to August 2016) S No

Borewell numbers

WQIavg (Post Monsoon)

Quality rating

1 2 3 4 5 6

NBW-1 NBW-2 NBW-3 NBW-4 NBW-5 NBW-6

82.76 85.98 74.46 88.15 89.04 93.53

Good Good Good Good Good Excellent

WQIavg (PreMonsoon) 70.33 84.3 77.54 89.48 91.71 93.52

Quality rating

WQIavg (Monsoon)

Quality rating

Good Good Good Good Excellent Excellent

83.31 81.7 80.88 75.37 75.82 77.09

Good Good Good Good Good Good

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WQI Based Studies on Groundwater Quality at Andhra University Campus, Visakhapatnam (IJSTE/ Volume 3 / Issue 09 / 044)

7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

NBW-7 NBW-8 NBW-9 NBW-10 NBW-11 NBW-12 SBW-1 SBW-2 SBW-3 SBW-4 SBW-5 SBW-6 SBW-7 SBW-8 SBW-9 SBW-10 SBW-11 SBW-12 SBW-13

93.53 84.46 86.47 82.01 58.27 101.62 89.83 86.41 72.46 89.04 90.22 82.98 78.59 90.57 94.08 86.81 85.52 77.68 82.79

Excellent Good Good Good Medium Excellent Good Good Good Good Excellent Good Good Excellent Excellent Good Good Good Good

93.52 85.65 80.9 80.97 87.11 70.48 91.52 87.98 74.7 85.62 84.61 71.89 75.05 81.61 90.05 87.61 89.61 77.04 84.18

Excellent Good Good Good Good Good Excellent Good Good Good Good Good Good Good Excellent Good Good Good Good

77.09 88.93 95.59 71.81 87.63 90.02 93.58 91.74 88.92 73.56 87.44 87.38 78.52 80.29 92.01 73.2 88.63 78.75 84.36

Good Good Excellent Good Good Excellent Excellent Excellent Good Good Excellent Good Good Good Excellent Good Good Good Good

Fig. 3: Seasonal variations of NSFWQI in North campus, AU (November 2015 to October 2016)

Fig. 4: Seasonal variations of NSFWQI in South campus, AU (November 2015 to October 2016)

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WQI Based Studies on Groundwater Quality at Andhra University Campus, Visakhapatnam (IJSTE/ Volume 3 / Issue 09 / 044)

V. CONCLUSIONS The average WQI values are found to be 28.01, 24.25 and 32.07 w.r.t Post-Monsoon, Pre-Monsoon and Monsoon seasons in WAIWQI method. The average WQI values obtained are 75.77, 83.49 and 83.29 w.r.t Post-Monsoon, Pre-Monsoon and Monsoon seasons in NSFWQI method. From the above cited values, it is concluded that the groundwater in the study area is good enough for drinking purposes in all season.

ACKNOWLEDGEMENTS The authors acknowledge Department of Science and Technology (DST), New Delhi and Andhra University, Visakhapatnam for sponsoring a Research project under which the present work is carried out.

REFERENCES [1] [2] [3] [4] [5] [6] [7] [8]

Curtis G.Cude, Oregon Water Quality Index a Tool for Evaluating Water Quality Management Effectiveness, Journal Of The American Water Resources Association, VOL. 37, NO. 1, FEBRUARY 2001 A. Gibrilla, Application of Water Quality Index (WQI) and multivariate Analysis for Groundwater Quality Assessment of the Birimian and Cape Coast Granitoid Complex: Densu River Basin of Ghana, Water Qual Expo Health (2011) 3:63–78 Li Pei-Yue et.al, Groundwater Quality Assessment Based on Improved Water Quality Index in Pengyang County, Ningxia, Northwest China, ISSN: 09734945; E-Journal of Chemistry, 2010, 7(S1), S209-S216 Mohammad Reza Mohebbia et.al, Assessment of water quality in groundwater resources of Iran using a modified drinking water quality index (DWQI), Ecological Indicators 30 (2013) 28–34 Prashant N. Rajankar et.al, Groundwater quality and water quality index at Bhandara District, Environ Monit Assess (2011) 179:619–625 Ravi Kant Dubey et.al, Ground Water Quality and Water Quality Index of Dwarka District of National Capital of India, International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 Rupal et.al Quality Characterization of Groundwater using Water Quality Index in Surat city, Gujarat, India, International Research Journal of Environment Sciences, Vol. 1(4), 14-23, November (2012) Sanjib Das et.al, Development Of Water Quality Index For Groundwater In Kolkata City, West Bengal, India, ARPN Journal of Engineering and Applied Sciences, VOL. 8, NO. 12, December 2013

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