Adjacent to the Fourth Water Recycling plant in Xi'an, a water reuse pilot station offers residents car washing self-service using reclaimed water. "The car wash here is cheap, with the prices as low as 10 yuan ($1.38) per wash," said a resident surnamed Zhang.

The service is part of the city's broader water conservation and environmental sustainability efforts.

"The car wash here utilizes reclaimed water treated by the local sewage treatment plant, and the water flow can reach about 100 cubic meters per hour. It can accommodate up to 10 cars simultaneously," said Song Jiahao, a staff member at the recycling water plant.

Beyond car washes, Xi'an has also expanded the use of reclaimed water to industrial use, green space irrigation, urban water use and agricultural irrigation.

Over the years, Xi'an has significantly boosted its sewage treatment capacity, enhancing both quantity and quality.

Since 2012, the city has built and upgraded 39 urban sewage treatment plants in addition to the existing 46. This expansion has increased the total treatment capacity from 1.51 million cubic meters per day to 4.07 million cu m per day, marking a 270 percent increase.

Xi'an has made substantial progress in water reuse with annual reclaimed water usage exceeding 400 million cu m, an 11-fold increase from less than 3 percent to 34.3 percent over the past decade. The city now boasts a reclaimed water pipeline network totaling over 310.14 kilometers.