This plot shows the amount of SARS-CoV-2 viral RNA detected in two Flagstaff, Arizona water reclamation plants -- Wildcat Hill (WCH - Orange) and Rio de Flag (Rio - Purple) -- influent and the number of COVID-19 cases within Flagstaff (gray line and shaded region)





These plots show the amount of Norovirus RNA detected in two Flagstaff, Arizona, water reclamation plants -- Wildcat Hill (WCH - Orange) and Rio de Flag (Rio - Purple) -- influent and additional testing sites within Flagstaff (Additional Sites - Green). Using the buttons below, you can toggle between viewing genogroups I and II.





Human case data is provided on a weekly basis from Coconino County Health and Human Services. The weekly case count runs from Sunday through Saturday.


Project Information

  • Wastewater-based surveillance analyzes wastewater samples to determine the exposure to and circulation of pathogens in a population. The wastewater is generated by the people in a particular community or setting, contributing to a sewage treatment plant catchment.
  • Wastewater surveillance has gained significant traction during the COVID-19 pandemic, as viral shedding can be detected in wastewater samples from both symptomatic and asymptomatic individuals about a week before human cases are identified. The utility of wastewater surveillance spans well beyond COVID-19 and can be used as an early indicator of viral pathogen circulation in a community and to inform the public health response.
  • This effort is possible due to a multi-agency collaboration between TGen North, Coconino County, and the City of Flagstaff, where the overarching goal is to provide Flagstaff residents with a better understanding of what might be causing illness in the community. We are always expanding our assays and expect to provide additional data on this site.

Samples are tested for the presence of SARS-CoV-2 (the virus that causes COVID-19) and Norovirus; viral load is quantified.

  • Wildcat Hill Wastewater Treatment Plant (WCH): plant personnel collect a 1 gallon composite sample over 24 hours once weekly (Tuesday through Wednesday mornings), and we collect two 50mL samples of that composite sample for infectious disease testing.
  • Rio de Flag Wastewater Treatment Plant (Rio): plant personnel collect a 1 gallon composite sample over 24 hours once weekly (Tuesday through Wednesday mornings) for the first two weeks of each month, and we collect two 50mL samples of that composite sample for infectious disease testing.
  • For additional questions about the general operations of Wildcat Hill and Rio de Flag Wastewater Treatment Plant, please see https://www.flagstaff.az.gov/120/Water-Reclamation-Plants

We have additional sites that are sampled more sporadically over time, and have grouped them all as "Additional Sites". Generally, these sites provide more information about a particular population, but are useful for better understanding how outbreaks are occurring over time.

Questions can be directed to [email protected]


More information regarding SARS-CoV-2 can be found here
App last updated 2022-11-16