As darkness settles over Fuzhou in East China's Fujian province, lights from the riverbanks shimmer on the Minjiang River as sightseeing boats, with sightseeing boats gliding across the water.

For many passengers, the most noticeable change is what is missing: the smell of diesel and the constant rumble of engines.

Since 2019, older diesel-powered tourist boats have gradually been replaced by electric and other new energy vessels on the city's popular night cruise route.

"The old boats gave off a strong diesel smell and a lot of noise," said Chi Jin, an official with the Fuzhou Maritime Safety Administration. "With electric boats, the ride is quieter, and passengers can enjoy the river without fumes or engine noise."

According to the local maritime authority, the electric vessels use about 48 percent less energy and reduce carbon emissions by about 54 percent compared with the diesel boats used as a benchmark.

The shift to cleaner propulsion is also being accompanied by tighter controls on vessel waste.

Domestic sewage and oily water are transferred through dedicated pipes to reception facilities at the pier before being sent to municipal treatment plants or specialized disposal facilities. Garbage is sorted on board and collected as part of the city's waste management system.

"Sewage, oily water and garbage are all taken ashore for treatment," said Zhou Yujian, head of hazardous cargo and pollution prevention at the Fuzhou Maritime Safety Administration. "The aim is simple: nothing should be discharged directly into the river."

Maritime authorities also monitor the night cruises through a digital platform, enabling officers on shore to track vessel movements and respond more quickly to emergencies. Additional inspections and onboard supervision are arranged during holidays and other periods of heavy passenger traffic.

The use of smart technology extends beyond the cruise route.

At Jiangyin Port, navigation aids are being equipped with weather sensors and automatic identification system equipment. Drones are also being used to inspect buoys and other equipment in waters where reefs, fishing nets, and terminals handling hazardous cargo can complicate navigation.

"The navigation aids do more than mark the channel now — they can collect information and warn vessels of danger ahead," said Chen Jingui, a manager at the Fuqing Strait Power Generation, which handles shipments of large wind-power equipment through the port.

For tourists, the transition means a quieter evening on the Minjiang River. Behind that experience is a broader system that combines cleaner vessels, shore-based waste treatment, digital monitoring and smarter navigation support, making the river more pleasant for passengers while reducing its environmental impact.