Environmental authorities observed per cent of them last year, the Chinese Ministry of Environmental Protection said its annual Environment Condition report.
They also conducted tests at 338 cities' drinking water sources, and found the water in nearly three per cent of them was unfit for drinking.
There were also some improvements in 2015.
For example, the number of deaths in floods dropped 76 per cent from the previous year, while the number of residents affected by floods and the area affected by floods declined 46 per cent and 45 per cent respectively, state-run Xinhua news agency reported.