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.
| 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 |