Serial number

Classification

Class I

Class II

Class III

Class IV

Class V

Standard value

project

1

Water temperature (℃)

The variation of environmental water temperature caused by human activities should be limited to: weekly average maximum temperature rise ≤ 1, weekly average maximum temperature drop ≤ 2

2

PH (dimensionless)

6~9

3

dissolved oxygen

≥

Saturation rate 90% (or 7.5)

6

5

3

2

4

Permanganate index

≤

2

4

6

10

15

5

Chemical oxygen demand (COD)

≤

15

15

20

30

40

6

Five day biochemical oxygen demand (BOD5)

≤

3

3

4

6

10

7

Ammonia nitrogen (NH3-N)

≤

0.15

0.5

1.0

1.5

2.0

8

Total phosphorus (as P)

≤

0.02 (Lake and reservoir o.01)

0.1 (Lake, reservoir o.025)

0.2 (Lake, reservoir O.05)

0.3 (Lake, reservoir o.1)

0.4 (Lake, reservoir O.2)

9

Total nitrogen (Lake, reservoir, n)

≤

0.2

0.5

1.0

1.5

2.0

10

copper

≤

0.01

1.0

1.0

1.0

1.0

11

zinc

≤

0.05

1.0

1.0

2.0

2.0

12

Fluoride (as F -)

≤

1.0 

1.0

1.0

1.5

1.5

13

selenium

≤

0.01 

0.01

0.01

0.02

0.02

14

arsenic

≤

0.05

0.05

0.05

0.1

0.1

15

mercury

≤

0.00005

0.00005

0.0001

0.001

0.001

16

cadmium

≤

0.001

0.005

0.005

0.005

0.01

17

Chromium (hexavalent)

≤

0.01

0.05

0.05

0.05

0.1

18

lead

≤

0.01

0.01

0.05

0.05

0.1

19

cyanide

≤

0.005

0.05

0.02

0.2

0.2

20

Volatile phenol

≤

0.002

0.002

0.005

0.01

0.1

21

Petroleum

≤

0.05

0.05

0.05

0.5

1.0

22

Anionic surfactant

≤

0.2 

0.2

0.2

0.3

0.3

23

sulfide

≤

0.05

0.1

0.2

0.5

1.0

24

Fecal coliform group (piece / L)

≤

200

2000

10000

20000

40000