BEIJING — China's water quality improved in the first four months of the year, according to a report issued by China's Ministry of Ecology and Environment.

The report showed that 81.9 percent of surface water was graded Class I to III (good quality) from January to April, up 1 percentage point from the same period last year, while the figure for Class V water fell 0.9 percentage points year-on-year to 2.1 percent.

Surface water quality in China is divided into five classes, with Class I being the best.

For major rivers, including the Yangtze and Yellow rivers, 83.8 percent of the water quality was graded Class I to III in the first four months, up 1.5 percentage points year-on-year, and 2.1 percent was graded Class V, down 1.1 percentage points year-on-year.

In 2020, China reported improved air and water quality as well as reduced carbon dioxide emissions amid the country's efforts to boost green development, an official report showed in March.