Qidong under clear skies. [Photo/WeChat account: qidongfabu]

Qidong, a county-level city in Nantong, Jiangsu province, recorded an annual average PM2.5 concentration of just 23.4 micrograms per cubic meter, with the proportion of days with good or excellent air quality reaching 86 percent in 2025, according to Qidong Ecology and Environment Bureau.

Qidong's air quality remained among the best in Jiangsu, with its PM2.5 concentration ranking first in the province for seven consecutive years. The strong performance has continued this year. From January to July, the county's average PM2.5 concentration stood at 24.2 mcg per cu m, ranking first in the province.

The improvement comes from targeted measures to curb pollution from key sources.

Qidong has strengthened industrial emission controls, focusing on both PM2.5 and ozone pollution. This year, the county has implemented 33 air pollution control projects, reducing emissions of major pollutants such as volatile organic compounds and nitrogen oxides by more than 300 metric tons.

Technology has brought greater precision to pollution monitoring. Qidong now operates 69 micro air-quality monitoring stations that run around the clock, forming a dense, data-rich surveillance network. In the first half of 2026, 35 tower-mounted video monitoring units and a drone base were added, strengthening an integrated monitoring network that covers ground-level sensors, aerial surveillance, and real-time data transmission.

The county has also doubled down on efforts to control vehicle emissions. Since the beginning of the year, authorities have carried out roadside inspections on 245 diesel trucks and phased out 33 China II non-road mobile machinery units and 203 China IV-and-below diesel trucks.