Wastewater testing for coronavirus is underway in some North Dakota cities and expanding to others, providing data that state and local officials hope can identify trends in communities.

Those involved in the research say the testing, though an emerging science, offers a certain measure of coronavirus presence, and is potentially an earlier indicator of active cases than testing of people. Wastewater testing could eventually supplement the public health response and help inform decision-making.

North Dakota's Department of Environmental Quality is spearheading the study begun in mid-July in Bismarck, Fargo and Grand Forks. It's funded by $65,000 in federal CARES Act coronavirus aid that includes a $50,000 grant for North Dakota State University.

Mandan, West Fargo and Williston also are participating, and more cities have agreed to as well or have been asked to participate. Wastewater samples are delivered to NDSU in Fargo for lab analysis.