Last updated October 2, 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.
Glenwood Springs
Pueblo
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.
CO Springs - Las Vegas
Metro WW - Clear Creek
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.
Aspen
Aurora
Durango
Grand Junction - Persigo
Greeley
Steamboat Springs
Telluride
Upper Blue SD - Breckenridge
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.
Alamosa
Centennial Water & Sanitation District
Metro WW - NTP
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.
Boulder
CO Springs - JD Phillips
La Junta
Metro WW - Platte/Central
South Platte
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.