Parameter

2013

2014

2015

Mean ± SD

SE

NPI

Mean ± SD

SE

NPI

Mean ± SD

SE

NPI

pH

7.38 ± 0.16

0.05

0.87

7.45 ± 0.14

0.04

0.88

7.50 ± 0.26

0.08

0.88

Turbidity NTU

276.34 ± 141.05

40.72

55.27

327.42 ± 171.82

49.60

65.48

344.56 ± 130.58

37.70

68.91

Temperature ˚C

25.51 ± 0.80

0.23

0.85

25.76 ± 0.83

0.24

0.86

27.71 ± 2.58

0.74

0.92

Conductivity ms/cm

330.67 ± 38.84

11.21

0.33

299.11 ± 33.31

9.62

0.30

313.75 ± 85.56

24.70

0.31

TDS mg/L

231.47 ± 27.19

7.85

0.23

209.38 ± 23.32

6.73

0.21

217.88 ± 58.86

16.99

0.22

Ammonia (NH₃₎ mg/L

1.32 ± 0.51

0.15

2.64

1.37 ± 0.67

0.19

2.75

1.42 ± 0.71

0.21

2.85

Nitrite ( ${\text{NO}}_2^{-}$ ) mg/L

2.82 ± 5.62

1.62

0.94

0.70 ± 0.62

0.18

0.23

3.80 ± 1.83

0.53

1.27

Nitrate (NO₃) mg/L

20.75 ± 4.54

1.31

0.41

21.53 ± 4.65

1.34

0.43

24.18 ± 4.21

1.22

0.48

Chloride mg/L

18.92 ± 3.73

1.08

0.08

20.08 ± 2.91

0.84

0.08

27.73 ± 6.58

1.90

0.11

Total Alkalinity mg/L

58.17 ± 4.00

1.15

0.29

65.25 ± 7.59

2.19

0.33

127.08 ± 83.20

24.02

0.64

Total Hardness mg/L

84.33 ± 9.53

2.70

0.17

82.75 ± 4.11

1.19

0.17

94.92 ± 26.12

7.54

0.19

Calcium Hardness mg/L

56.50 ± 5.21

1.51

0.28

49.75 ± 5.94

1.72

0.25

59.33 ± 12.15

3.51

0.30

Mg Hardness mg/L

27.83 ± 11.68

3.37

0.19

33.00 ± 8.15

2.35

0.22

35.58 ± 16.18

4.67

0.24

Calcium mg/L

22.60 ± 2.09

0.60

0.11

19.90 ± 2.38

0.69

0.10

22.67 ± 4.69

1.35

0.11

Magnesium mg/L

6.55 ± 0.60

0.17

0.04

9.57 ± 2.36

0.68

0.06

8.74 ± 3.21

0.93

0.06

Arsenic mg/L

0.00 ± 0.00

0.00

0.00

0.00 ± 0.00

0.00

0.00

0.00 ± 0.00

0.00

0.00

Copper mg/L

1.61 ± 1.58

0.46

8.06

0.36 ± 0.14

0.04

1.79

2.38 ± 0.77

0.22

11.88

Lead mg/L

0.00 ± 0.00

0.00

0.00

0.00 ± 0.00

0.00

0.10

0.01 ± 0.03

0.01

0.83

Iron (Total) mg/L

1.73 ± 0.48

0.14

5.76

1.68 ± 0.64

0.18

5.61

1.69 ± 0.95

0.27

5.64

Zinc mg/L

0.66 ± 0.78

0.22

0.13

0.69 ± 0.55

0.16

0.14

2.35 ± 0.50

0.14

0.47

Fluoride mg/L

0.66 ± 0.44

0.13

0.44

0.70 ± 0.19

0.06

0.47

1.33 ± 0.43

0.12

0.89

Sulphate mg/L

13.83 ± 3.74

1.08

0.06

15.70 ± 4.10

1.18

0.06

16.92 ± 6.27

1.81

0.07

Phosphate mg/L

23.34 ± 4.35

1.37

4.67

24.55 ± 5.08

1.47

4.91

27.34 ± 4.71

1.36

5.47

Aluminium mg/L

2.29 ± 6.52

1.88

11.47

0.53 ± 0.22

0.06

2.65

0.34 ± 0.14

0.04

1.71

Manganese

0.35 ± 0.13

0.04

0.87

0.53 ± 0.15

0.04

1.32

1.35 ± 3.39

0.98

3.38

WQI

52.16

53.35

43.33