Since Taihu Lake's blue-green algae outbreak disrupted drinking water supplies to about 1 million people in Wuxi nearly two years ago, Mayor Mao Xiaoping is often asked about the city's measures against water pollution.

This year's top policymaking sessions are no exception, as the water in northern Jiangsu province's Yancheng city was discovered late last month to have been contaminated with highly toxic carbolic acid from a local chemical company.

So Mao has been facing a fresh round of inquiries about how to prevent such incidents from reoccurring and rising above the vicious circle of achieving economic development at the environment's expense.