Parameter

Observed mean value

Standard mean value

Unit weight (W_n)

Quality rating (q_n)

W_nq_n

pH

7.4

6.5 - 8.5

0.219

22

4.8

EC

1075

300

0.371

343

127

Alkalinity

447

120

0.0155

394

6.1

Hardness

503

300

0.0062

143

0.9

Ca

68

75

0.025

87

2.2

Mg

16

30

0.061

52

3.2

37

250

0.0074

15

0.1

561

45

0.0412

1239

51

55

150

0.01236

34

0.4

DO

6.8

4.0

0.3723

53

20

SW_n = 1.131

Sq_n = 2382

SW_nq_n = 216