Citizen monitoring of waterways decreases pollution in China by supporting government action and oversight.

Water pollution is a persistent problem in China, in part, because local governments fail to implement water quality standards set by national and provincial authorities. These higher authorities often lack regular information about the immediate and long-term achievement of remediation targets. Accordingly, central authorities have encouraged nongovernmental organizations to monitor local governments' remediation efforts. This study examines whether nongovernmental monitoring of urban waterways improves water quality by facilitating oversight of local governments or instigating public action for remediation. We randomly assigned urban waterways in Jiangsu province previously identified for remediation to be monitored by a partner nongovernmental organization for 15 mo. We further randomized whether the resulting information was disseminated to local and provincial governments, the public, or both. Disseminating results from monitoring to local and provincial governments improved water quality, but disseminating results to the public did not have detectable effects on water quality or residents' pursuit of remediation through official and volunteer channels. Monitoring can improve resource management when it provides information that makes local resource managers accountable to higher authorities.