An autumn view of Thousand Islets Lake in Chun'an county in East China's Zhejiang province. [Photo/VCG]

East China's Zhejiang province ranked first in water and atmospheric environment quality among the three provinces and one municipality that constitute the Yangtze River Delta region, according to the recently released 2020 Report on Zhejiang's Ecological Environment Situation.

Fang Min, director of the Zhejiang Provincial Department of Ecology and Environment, said that Zhejiang maintained its nationwide leadership in environment-related supervision and regulation in 2020, and that the public is well aware of the improvement of its ecological environment.

Data shows that Zhejiang residents' satisfaction rate about the province's ecological environment has risen for 10 consecutive years, as well as that the number of their public complaints and proposals has decreased for four consecutive years.

In the 11 Zhejiang cities at or above prefecture-level, the average percentage of days with excellent or good results in air quality index (AQI) throughout 2020 was 93.3 percent, while the average PM2.5 (particulate matter with a diameter of less than 2.5 micrometers) density throughout 2020 was 25 micrograms per cubic meter, down 19.4 percent from the previous year.

As much as 94.6 percent of the surface water monitoring sections in Zhejiang was rated as Class III (suitable for the cultivation of aquatic produce or swimming) or higher in 2020. All of the concentrated sources of drinking water for the province's 92 localities at or above county-level passed the quality test.

The sea areas rated as Class I or Class II, the highest two tiers in China's four-tier seawater quality grading system and indicative that the seawater is suitable for swimming, accounted for a record high of 43.4 percent of the province's offshore areas in 2020, up 11.4 percent from the previous year.

Last year, Zhejiang authorities issued a regulation on how to reward whistle-blowers that report environmental law offences, setting the highest bonus at 500,000 yuan ($78,100). This was aimed at encouraging Zhejiang residents from all walks of life to pay closer attention to environmental issues.