The physical, chemical, and microbial characteristics of TWW are analyzed to verify its suitability for agriculture and to examine the extent of reduction in fertilizer application. The TWW sample is collected from the wastewater treatment plant located in the neighboring district, Madurai, and its physicochemical characteristics are analyzed. The results of the TWW analysis are compared against the FAO standards for irrigation water quality (FAO, 1985) and found to be within acceptable limits (Table 7).
Physicochemical properties of the TWW.
| Parameter . | Unit . | Concentration . | FAO standards . | ||
|---|---|---|---|---|---|
| None . | Slight to moderate . | Severe . | |||
| TDS | mg/l | 1,310.00 | <450 | 450–2,000 | >2,000 |
| EC | ds/cm | 0.9 | <0.7 | 0.7–3.0 | >3.0 |
| Calcium | mg/l | 56.00 | – | – | – |
| Magnesium | mg/l | 6.80 | – | – | – |
| Sodium | me/l | 3.73 | <3 | 3–9 | 9 |
| Chloride | mg/l | 13.98 | <4 | 4–10 | >10 |
| Sulphate | mg/l | 178.00 | – | ||
| Nitrate | mg/l | 12.50 | – | ||
| Ammonia | mg/l | 2.00 | – | ||
| Phosphate | mg/l | 1.20 | – | ||
| Potassium | mg/l | 11.50 | – | ||
| SAR | mg/l | 2.88 | – | ||
| pH | mg/l | 8.20 | 6.5–8.4 | ||
| BOD | mg/l | 12.00 | – | ||
| COD | mg/l | 45.00 | – | ||
| Total Nitrogen | mg/l | 53.00 | – | ||
| Zinc | mg/l | 1.20 | 2.0 | ||
| Manganese | mg/l | <0.10 | 0.2 | ||
| Iron | mg/l | 0.20 | 5.0 | ||
| Borates | mg/l | <0.10 | – | ||
| Copper | mg/l | 0.05 | 0.2 | ||
| E. coli | CFU/ml | 80.00 | – | ||
| Coliform | CFU/ml | 650.00 | – | ||
| Salmonella | CFU/ml | Absent | – | ||
| Parameter . | Unit . | Concentration . | FAO standards . | ||
|---|---|---|---|---|---|
| None . | Slight to moderate . | Severe . | |||
| TDS | mg/l | 1,310.00 | <450 | 450–2,000 | >2,000 |
| EC | ds/cm | 0.9 | <0.7 | 0.7–3.0 | >3.0 |
| Calcium | mg/l | 56.00 | – | – | – |
| Magnesium | mg/l | 6.80 | – | – | – |
| Sodium | me/l | 3.73 | <3 | 3–9 | 9 |
| Chloride | mg/l | 13.98 | <4 | 4–10 | >10 |
| Sulphate | mg/l | 178.00 | – | ||
| Nitrate | mg/l | 12.50 | – | ||
| Ammonia | mg/l | 2.00 | – | ||
| Phosphate | mg/l | 1.20 | – | ||
| Potassium | mg/l | 11.50 | – | ||
| SAR | mg/l | 2.88 | – | ||
| pH | mg/l | 8.20 | 6.5–8.4 | ||
| BOD | mg/l | 12.00 | – | ||
| COD | mg/l | 45.00 | – | ||
| Total Nitrogen | mg/l | 53.00 | – | ||
| Zinc | mg/l | 1.20 | 2.0 | ||
| Manganese | mg/l | <0.10 | 0.2 | ||
| Iron | mg/l | 0.20 | 5.0 | ||
| Borates | mg/l | <0.10 | – | ||
| Copper | mg/l | 0.05 | 0.2 | ||
| E. coli | CFU/ml | 80.00 | – | ||
| Coliform | CFU/ml | 650.00 | – | ||
| Salmonella | CFU/ml | Absent | – | ||