Had there been proper interaction between the Yuhang local government in Hangzhou, Zhejiang province, and residents, the construction of a garbage incinerator would not have led to a public protest on Saturday. More importantly, proper communication between the local authorities and residents could have prevented the public protest from turning into a riot, in which police vehicles were overturned and torched, and police officers attacked.

This is not the first time that residents have protested against such a project. In 2007, Beijing authorities had to defer plans to build a garbage incinerator because of strong opposition from local residents. The public protest against a P-Xylene project in Maoming city, Guangdong province, in late March also turned violent, in which public facilities were vandalized.

Incineration is considered the most environmentally friendly way of disposing garbage, much safer than landfills, which in most cases contaminate groundwater and soil, and occupy large tracts of land. But some people are not ready to accept this fact. They fear that incinerators will emit hazardous gases harmful to human health, and refuse to be convinced by local governments' reassurances. Perhaps lack of trust in local governments' claims is to blame for this.

Bringing to justice the vandals and violent protesters who beat up police officers in Yuhang should not be a problem. But it is more important to take measures to prevent such incidents, for which the local government has to realize that its trustworthiness and status among residents have taken a beating and it needs to restore that. Yet promising not to start work on the project without the consent of the majority of residents or to get the residents to agree to a single project by producing convincing evidence them it is environmentally friendly will not be enough for the local government to win back public trust.

Pollution-related incidents caused by local governments' projects over the past few years have forced a majority of people to believe that local officials always place economic growth above environmental concerns. Therefore, local governments across the country have to do some hard work - such as launching a series of projects that will provide real benefit to residents - before they can win back people's trust.

Inversely, only when a local government regains its trustworthiness can it establish a proper interaction mechanism with residents. Call it the virtuous cycle of local economic development and social progress, if you will.