Table 2 Percentage of National Routine Monitoring River Sections Falling into Different Classes of Water Quality in China’s Seven Major River Basins in 2015.

From: Spatial Regression and Prediction of Water Quality in a Watershed with Complex Pollution Sources

Category

River Basin

Number of Monitoring Sections

Class I (%)

Class II (%)

Class III (%)

Class IV (%)

Class V (%)

Worse than Class V (%)

Main Stem

Yangtze

42

7.1

38.1

52.4

0.0

2.4

0.0

Yellow

26

3.8

46.2

38.5

11.5

0.0

0.0

Pearl

18

5.6

77.8

11.1

5.6

0.0

0.0

Songhua

16

0.0

18.8

62.5

12.5

0.0

6.2

Huai

10

0.0

30.0

50.0

20.0

0.0

0.0

Hai

2

0.0

0.0

0.0

0.0

50.0

50.0

Liao

14

0.0

7.1

7.1

64.3

14.3

7.1

Main Tributary

Yangtze

118

2.5

61.0

22.9

8.5

0.8

4.2

Yellow

36

0.0

19.4

22.2

27.8

8.3

22.2

Pearl

26

3.8

73.1

15.4

0.0

0.0

7.7

Songhua

34

0.0

8.8

64.7

11.8

5.9

8.8

Huai

42

0.0

7.1

28.6

26.2

21.4

16.7

Hai

50

6.0

14.0

22.0

8.0

6.0

44.0

Liao

6

0.0

0.0

0.0

66.7

0.0

33.3