Aquatic Pollution and Coastal Management

Unit 1 : Classification of aquatic pollution

1.7.Water Quality Criteria For Fresh Water

Designated Best Use	Class of water	Criteria
Drinking water source without conventional treatment but after disinfection	A	1. Total coliform organisms (MPN/100 ml )50 or less 2. pH between 6.5 and 8.5 3. Dissolved oxygen 6 mg/l or more 4. Biochemical oxygen demand (5 days 20oC) 2 mg/l or less
Outdoor bathing (organized)	B	1. Total coliform organisms (MPN/100 ml ) 500 or less 2. pH between 6.5 and 8.5 3. Dissolved oxygen 5 mg/l or more 4. Biochemical oxygen demand (5 days 20oC ) 3 mg/l or less
Drinking water source after conventional treatment and disinfection	C	1. Total coliforms organisms( MPN/100 ml ) 5000 or less 2. pH between 6 and 9 3. Dissolved oxygen 4 mg/l or more 4. Biochemical Oxygen Demand (5 days 20oC ) 3mg/l or less
Propagation of wildlife and fisheries	D	1. pH between 6.5 and 8.5 2. Dissolved oxygen 4 mg/l or more 3. Free ammonia (as N) 1.2 mg/l or less
Irrigation, industrial cooling, controlled waste disposal.	E	1. pH between 6.0 and 8.5 2. Electrical conductivity at µ mhos/cm maximum.2250 3. Sodium absorption ratio maximum. 26 4. Boron Maximum. 2 mg/l
	Below-E	Not meeting A, B, C, D & E criteria