Table 3.
BIS (2012) limits of Drinking Water parameters, timelines and predicted-cumulative extent of <permissible and >permissible categories, KRB, Kerala.
| No | Parameter | Sampling Year |
BIS Drinking Water Specification |
Predicted Extent in KRB, km2 |
||
|---|---|---|---|---|---|---|
| Acceptable limit | Maximum limit | <Permissible limit | >Permissible limit | |||
| 1 | pH | 2021 | 6.5 to 8.5 | 6.5 to 8.5 | 699.41 | 2.59 |
| 2022 | 692.04 | 9.96 | ||||
| 2 | Total Dissolved Solid (TDS), mg/l | 2021 | 500 | 2000 | 661.18 | 40.82 |
| 2022 | 653.10 | 48.90 | ||||
| 3 | Calcium (Ca2+), mg/l | 2021 | 75 | 200 | 702.00 | 702.00 |
| 2022 | 702.00 | 702.00 | ||||
| 4 | Magnesium (Mg2+), mg/l | 2021 | 30 | 100 | 683.52 | 18.48 |
| 2022 | 627.56 | 74.44 | ||||
| 5 | Total Hardness (TH), mg/l | 2021 | 200 | 600 | 685.58 | 16.42 |
| 2022 | 680.31 | 21.69 | ||||
| 6 | Chloride (Cl-), mg/l | 2021 | 250 | 1000 | 675.01 | 26.99 |
| 2022 | 668.36 | 33.64 | ||||
| 7 | Nitrate (NO3-), mg/l | 2021 | 45 | 100 | 702.00 | 702.00 |
| 2022 | 702.00 | 702.00 | ||||
| 8 | Nitrite (NO2-), mg/l | 2021 | 3 | - | 702.00 | 702.00 |
| 2022 | 702.00 | 702.00 | ||||
| 9 | Silicate (SiO4), mg/l | 2021 | 30 | - | 702.00 | 702.00 |
| 2022 | 702.00 | 702.00 | ||||
| 10 | Sulphate (SO4), mg/l | 2021 | 200 | 400 | 702.00 | 702.00 |
| 2022 | 702.00 | 702.00 | ||||