A version of this article originally appeared in Dateline.

UC Davis is deploying one more system to potentially identify and halt an outbreak of COVID-19 on campus — the campus sewer system.

Facilities Management employees are working with UC Davis researchers to collect samples from the campus wastewater treatment system to test for trace evidence of the coronavirus.

Testing so far has been located solely at the campus wastewater treatment plan and has returned mostly negative results. The team occasionally detected low levels of the virus in samples collected in late August and September, consistent with cases of COVID-19 reported by the campus.

Starting this week the team will begin installing eight samplers at various campus locations that could help identify buildings where occupants should be tested more carefully, if evidence of the virus is found.

The testing process is being managed by a multidisciplinary team of researchers, led by:

• Heather Bischel, assistant professor in the Department of Civil and Environmental Engineering, with a focus on sanitation systems, water quality, virus monitoring and pathogen inactivation
• Karen Shapiro, associate professor in the School of Veterinary Medicine, with a focus on pathogen detection, waterborne diseases and human public health

Similar wastewater testing is being done by researchers at 76 other universities around the globe, according to a map from UC Merced. This process made national headlines earlier this year when wastewater testing at the University of Arizona uncovered evidence of the coronavirus in a specific residence hall, prompting additional testing that identified two asymptomatic students — potentially warding off an outbreak.

The first eight samplers arrived on campus last week, with four more expected to arrive later this month. Testing is expected to begin October 15.

Once fully deployed, the samplers may be used at up to 22 campus locations per week, collecting composite samples over a 24-hour period.

The campus team of staff and researchers also expect to assist the City of Davis in implementing a similar program, as they work toward ordering their own 14 samplers to deploy throughout the city’s wastewater systems.