Table 3.1
Standard values for terrestrial surface water bodies (rivers, lakes)
Class Standard values
Hydrogen ion concentration index (pH)
Dissolved oxygen (DO) (mg/l)
Biological oxygen
demand (BOD) (mg/l)
Suspended
solids
(SS) (mg/l)
E. coli
(CFU/100 ml)
Ammonia nitrogen
(NH
3 -N) (mg/l)
Total phosphorus (TP) (mg/l)
A
6.5–8.5
Over 6.5
Less than 1
Less than 25
Less than 50
Less than 0.1
Less than 0.02
B
6.0–9.0
Over 5.5
Less than 2
Less than 25
Less than
5000
Less than 0.3
Less than 0.05
C
6.0–9.0
Over 4.5
Less than 4
Less than 40
Less than
10,000
Less than 0.3
–
D
6.0–9.0
Over 3
–
Less than 100
–
–
–
E
6.0–9.0
Over 2
–
No
floating
material and no
oil
–
–
–
Marine surface water bodies
Class Standard values
Hydrogen ion concentration
index (pH)
Dissolved oxygen (DO) (mg/l) Biological oxygen demand
(BOD) (mg/l)
E. coli
(CFU/100 ml)
A
7.5–8.5
Over 5.0
Less than 2
Less than 1000
B
7.5–8.5
Over 5.0
Less than 3
–
C
7.0–8.5
Over 2.0
Less than 6
–
Notes
The following units are used for standard values in the foregoing standards:
6. pH: pH value
7. E. coli:
colony forming units per 100 ml water sample
8. Others: milligram/liter
3 Surface Water Quality and Analysis
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