Physical examination Control Pre-treatment Post-treatment Pre-treatment Post-treatment Pre-treatment Post-treatment Pre-treatment Post-treatment Aminjikarai Aminjikarai Ethiraj college Ethiraj college Adyar Adyar Napier's Bridge Napier's Bridge Appearance Clear Turbid Turbid Turbid Turbid Turbid Turbid Turbid Clear Colour (pt.co-scale) Colourless Black Green Black Green Black Green Colourless Colourless Odour None Foul smell None Foul smell None Foul smell None None None Turbidity NT Units 3.2 98.2 30 78.6 73.2 36.8 24.4 7.1 1.2 Electrical Conductivity Micro mho/cm 729 5300 2240 2510 2200 10400 2401 45100 43200 Total dissolved Solidsmg/L 729 3710 1568 1757 1540 7280 2401 43200 31570 CHEMICAL EXAMINATION                   pH 7.99 7.52 8.28 7.94 8.23 7.7 8.26 6.92 7.19 Total Alkalinity as CaCo₃mg/L 160 608 340 512 336 472 356 120 172 Total Haardness as CaCo₃mg/L 126 600 510 380 480 1000 880 2500 10200 Calciun as Ca mg/L 38 176 156 108 140 280 248 800 3120 Magnesium as Mg mg/L 8 38 29 26 31 72 62 120 576 Sodium as Na mg/L 101 870 259 375 236 1770 114 8400 4640 Potassium as K mg/L 9 65 17 30 17 110 13 550 230 Iron as Fe mg/L 0.34 0.51 0.81 0.63 1.09 0.44 0.92 0.41 0.53 Free Ammonia as NH₃ mg/L 0.28 12.9 3.52 11.32 2.79 10.26 1.75 6.77 0.52 Nitrate as NO₂ mg/L 1.13 0.41 0.09 0.02 0.28 0.04 0.05 0.72 0.05 Nitrate as NO₃ mg/L 8 20 32 14 26 14 16 14 7 Chloride as CLmg/L 98 1275 495 450 500 3300 565 14500 13800 Fluoride as F mg/L 0.47 0.97 0.78 0.84 0.82 0.64 0.61 0.61 0.39 Sulphate as SO₄ mg/L 24 107 36 62 37 158 47 221 132 Phosphate as PO₄ mg/L 0.13 0.22 0.21 0.32 0.25 0.05 0.22 0 0.2 Tidys Test 4 hrs.as O₂ mg/L 1 16.2 6.8 12.3 6.1 11.8 3.7 7.9 1.9 C.O.D -mg/L 6.6 198 92.5 162 86.6 140 40.3 89 18.2 B.O.D -mg/L 3 90 38 60 33 54 18 34 8

Table 1: Analysis of different Physio-chemical parameters from four various sewage pre and post treated water