Parameter

2010

2011

2012

Mean ± SD

SE

NPI

Mean ± SD

SE

NPI

Mean ± SD

SE

NPI

pH

7.22 ± 0.09

0.03

0.85

7.12 ± 0.22

0.06

0.84

7.31 ± 0.15

0.04

0.86

Turbidity NTU

19 ± 2.33

0.67

3.81

23.09 ± 6.16

1.78

4.62

264.84 ± 182.62

52.72

52.97

Temperature ˚C

25 ± 0.51

0.15

0.85

25.41 ± 0.30

0.09

0.85

25.41 ± 0.30

0.09

0.85

Conductivity ms/cm

356 ± 35.64

10.29

0.36

370.56 ± 15.91

4.59

0.37

330.67 ± 38.84

11.21

0.33

TDS mg/L

183 ± 13.91

4.01

0.18

333.16 ± 522.22

150.75

0.33

231.47 ± 27.19

7.85

0.23

Ammonia (NH₃) mg/L

1 ± 0.81

0.05

1.58

1.20 ± 0.47

0.14

2.39

1.25 ± 0.53

0.15

2.50

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

0 ± 0.02

0.01

0.02

0.30 ± 0.20

0.06

0.10

0.65 ± 0.25

0.07

0.22

Nitrate (NO₃) mg/L

1 ± 0.08

0.02

0.02

2.05 ± 0.19

0.05

0.04

19.53 ± 2.77

0.80

0.39

Chloride mg/L

16 ± 0.65

0.19

0.06

15.25 ± 1.15

0.33

0.06

24.21 ± 12.53

3.62

0.10

Total Alkalinity mg/L

38 ± 4.93

1.42

0.19

57.75 ± 5.46

1.58

0.29

60.00 ± 4.88

1.41

0.30

Total Hardness mg/L

85 ± 7.68

2.22

0.17

85.25 ± 5.19

1.50

0.17

80.75 ± 7.01

2.02

0.16

Calcium Hardness mg/L

37 ± 5.84

1.69

0.19

33.25 ± 7.90

2.28

0.17

58.50 ± 6.62

1.81

0.29

Mg Hardness mg/L

48 ± 5.40

1.56

0.32

47.83 ± 9.47

2.73

0.32

22.25 ± 6.61

1.91

0.15

Calcium mg/L

15 ± 2.34

0.67

0.07

13.30 ± 3.16

0.91

0.07

23.40 ± 2.50

0.72

0.12

Magnesium mg/L

14 ± 1.57

0.45

0.09

13.87 ± 2.75

0.79

0.09

6.79 ± 0.73

0.21

0.05

Arsenic mg/L

0 ± 0.00

0.00

0.08

0.00 ± 0.01

0.00

0.25

0.00 ± 0.00

0.00

0.00

Copper mg/L

0 ± 0.17

0.05

1.03

0.16 ± 0.11

0.03

0.81

1.26 ± 0.79

0.23

6.30

Lead mg/L

0 ± 0.00

0.00

0.00

0.00 ± 0.00

0.00

0.17

0.00 ± 0.00

0.00

0.17

Iron (Total) mg/L

1 ± 0.41

0.12

3.15

1.21 ± 0.24

0.07

4.03

1.68 ± 0.48

0.14

5.60

Zinc mg/L

0.42 ± 0.18

0.05

0.08

0.66 ± 0.78

0.22

0.13

0.66 ± 0.78

0.22

0.13

Fluoride mg/L

0.43 ± 0.44

0.13

0.28

0.28 ± 0.17

0.05

0.19

0.95 ± 0.47

0.13

0.63

Sulphate mg/L

47.26 ± 12.90

3.72

0.19

17.95 ± 10.11

2.92

0.07

21.91 ± 2.75

0.79

0.09

Phosphate mg/L

16.46 ± 5.57

1.61

3.29

19.15 ± 2.40

0.69

3.83

22.21 ± 3.90

1.13

4.44

Aluminium mg/L

0.59 ± 0.72

0.21

2.93

0.23 ± 0.13

0.04

1.13

0.69 ± 0.54

0.16

3.47

Manganese

0.25 ± 0.12

0.03

0.63

0.52 ± 0.19

0.06

1.29

0.43 ± 0.24

0.07

1.07

WQI

74.95

73.5

49.7