Min.: Minimum level desired                                                                     Max. : Maximum allowable value 

• If the coliform is found to be more than the prescribed tolerance limits the criteria for coliform shall be satisfied if not more than 20 percent of samples show more than the tolerance limits specified and not more than 5 percent of samples show values more than 4 times the tolerance limits. There should be no visible discharge of domestic and industrial water into class ‘A’ water. In case of class ‘B’ and ‘C’ the discharges shall be so regulated/treated as to ensure maintenance of the stream standards.
• If the ambient water quality of the river is examined in the light of the tolerance limits prescribed, the classification arrived at on the basis of a single parameter may not necessarily be the same as that based on other parameters. In such cases the lowest class scored in respect of any one of the criteria should normally indicate the water quality status of a particular reach of the river.

1. Drinking water sources without conventional treatment but after disinfection.
2. Organized outdoor bathing.
3. Drinking water source with conventional treatment followed by disinfection.
4. Propagation of wild life and fisheries.
5. Irrigation, industrial cooling and controlled water disposal.

Source: www.cpcb.nic.in