The amount of water used in washing buses has become a concern raised by members of the city's top political advisory body, and they advocate installing equipment that conserves the resource.
Huang Xiaofeng and Huang Shiwei, members of the Shanghai committee of the Chinese People's Political Consultative Conference (CPPCC), said in a recent proposal that 3.3 million cubic meters of water is used annually on washing buses, according to their research, equal to the yearly water consumption of more than 18,000 households. And few bus companies employ water-conserving equipment, which could help reduce the amount of water needed by 55 percent to 70 percent.
Shanghai's 1,000-plus bus lines employ about 18,000 buses. Normally, each one is washed once a day, more if it rains.
"Water-conserving bus washing equipment costs 400,000 yuan ($63,000), and takes up an area of 300 square meters," said Zhao Jinhua, a manager at Shanghai Bus Yiqi, a corporation that operates more than 1,200 buses under Shanghai Bus Public Transportation (Group) Co Ltd.
Zhao said his company owns two sets of the equipment, but most of the buses still get an old-fashioned washing - by two workers with traditional water pumps and nozzles - at the 45 big bus stations around the city.
The two CPPCC members say the traditional method "wastes a lot of water", and they think that the government should subsidize bus companies' purchase of energy-efficient washing equipment that recycles much of the water.
"The problem is not just the money," said Zhao, who noted that the water-conserving machines take up too much space to be used in all of the stations where buses are washed.
Shen Jianhua, deputy head of the human resources and environment committee of the Shanghai committee of the CPPCC, said those machines would "definitely save water, but they would also cost more money and electricity".
"I think it's more important that the used water is recycled, because it contains oil and some harmful chemicals that should be processed before going into the drain," he said.
Most netizens on QQ BBS (online bulletin boards) support the suggestion. But some also raised doubts. "Three million cubic meters? It sounds big, while it is no more than the annual water consumption of a golf course," said a netizen named "kuilei".