Last updated November 20, 2024
Wastewater treatment facilities participating in the CDPHE Wastewater Surveillance Program submit two samples per week. A statistical time series model is used to determine the trend of SARS-CoV-2 viral concentrations for each individual facility for the date each sample is collected. We review these trends and determine their trend category each week based on the following criteria:
A steady increase means the viral concentrations of the two most recent samples reflect a statistically significant increase relative to earlier samples from that facility.
Grand Junction - Persigo
Metro WW - NTP
A simple increase means the viral concentrations of one out of the two most recent samples reflects a statistically significant increase relative to earlier samples from that facility.
Greeley
A plateau in the trend means there was no statistically significant change in the viral concentrations of the two most recent samples relative to earlier samples from that facility.
Alamosa
CO Springs - Las Vegas
Durango
Metro WW - Clear Creek
South Platte
A simple decrease means the viral concentrations of one out of the two most recent samples reflects a statistically significant decrease relative to earlier samples from that facility.
Aspen
Glenwood Springs
Steamboat Springs
A steady decrease means the viral concentrations of the two most recent samples reflect a statistically significant decrease relative to earlier samples from that facility.
Aurora
Boulder
CO Springs - JD Phillips
Centennial Water & Sanitation District
La Junta
Metro WW - Platte/Central
Pueblo
Telluride
Upper Blue SD - Breckenridge
Wastewater treatment facilities without two recent samples (within the last 15 days) OR facilities without enough samples to construct a trend model (< 5 samples in 3 weeks) are categorized as insufficient data.
Note: Trends are calculated with the SARS-CoV-2 viral concentration data from each individual facility; raw viral concentration levels cannot be compared between utilities due to the variability in collection time, influent flow rates, and differences in the size and characteristics of resident populations, among other factors.