Colorado Covid Wastewater Dashboard 

The chart below provides an estimate of the amount of Viral copies for 5 viruses in Wastewater per reporting utility. It shows COVID, RSV, Flu A&B, and EV-68. While all the viruses can be found in wastewater, the amount of virus in wastewater due to each infections is not the same for the various viruses.  As COVID-19 is a more systemic virus, it is more easily found in wastewater than Flu and RSV.  That said, it is useful to understand the scope of the various viruses presence in wastewater.    The most recent week is on the far right.  The chart begins in August 2024, when the 20-utility sentinel surveillance system began. 

Update 11/4.2024: CDPHE has changed its wastewater system again, and I no longer feel like using a regression model from the early pandemic is appropriate.  The site will continue to post summary  data only. 

Update 10/9/2024: CDPHE has changed its data system again, and until there is more clarity on the data, I will pause updates.  Please check back in about 2 weeks. 

Above, please feel free to tab through the various tabs of the spreadsheet to see the different relevant chart.  Some are presented below as well. 

Below is the median chart showing the last 6 months of data from the 20 utilities that continue to report. 

Below is the historical summary of Wastewater Summary trends.  The most recent week's trends (as published Wednesday) are at the far right of the chart.  (Updates temporarily paused as it is not appropriate to compare trends across lab phases)

Update: As of August 1, 2024:

CDPHE is no longer publishing wastewater data from all of the sites included in the original tool, meaning the original regression model will no longer work.  A revised version is in development and has now been published. It will update on Fridays as before.  The revised model relies on data from only 9 Utilities: 

Aurora, Boulder,  Colorado Springs - JD Phillips, Colorado Springs - Las Vegas, Greeley,  Metro WW - Clear Creek, Metro WW- Platte River Canyon, Pueblo, and South Platte.    

While the regression model uses less utilities, it actually showed better correlation with the Case Data than the previous version. The correlation for this  model  is r=.9766 (compared to .9677 for the last version and .9662 for the original version) and r-squared=0.9537 (compared to .9365 for the last version). The model is likely better because the utilities included are more similar in size and population served, and less likely to be skewed by smaller utilities experiencing a large isolated uptick in covid copies per liter. As with the previous model, it was built using the time period August 2020 through mid February 2022, when case reporting and wastewater were both available and reliable. 

It is also worth noting that in July 2023, CDPHE changed to "Lab Phase 2", a phase in which different laboratory equipment began being used to process wastewater samples.  CDPHE states that the levels in Lab Phase 2 cannot be compared to Lab Phase 1, but puts the data on the same chart with the same maximum and minimum.  Details on this change have been limited. The only difference I have noticed is that the minimum detectable level is 4,000 Covid Copies per Liter, while in lab phase 1, the minimum detectable level appeared to be much lower (the lowest level I saw reported was 400).  So when levels are VERY low, they are not comparable to previous low levels, but as levels are usually above 4,000 copies per liter (only 10% of all SARS-COV-2 Wastewater samples are below this level) this is not a significant concern.  It also seems that CDPHE changed historical data points to reflect this issue, as data points prior to this sentinel surveillance data set reported a variety of low values, but today the only level below 4000 is 2000. For example, the first data point for Greeley on 08/02/2020 was originally published as 3512.  It is now showing as 2000. Im not sure when this data was changed, but it should make the historical data MORE comparable to current data. This may be part of why the current model is more accurate than the old model. 

The image below compares the current model (shown with orange diamonds) to the previous model (shown with brown squares) and the State's reported cases (which as we know, severly underestimate the actual number of cases due to the closure of the free PCR sites and difficulty reporting home tests). Its clear from the image below that the revised model is very similar to the previous verion of the model.  it skews a little lower, and is a little less noisy than the previous version. Looking at the data points, it typically reports about 89 cases/day below the last version, with 70% of the weeks reporting lower than the previous version.     

Previous information:

Important Note: As of August 2023, some utilities have dropped out of the CDPHE Wastewater program, including two included in this model.  Per communication from CDPHE staff, the Wellington Water and Sewer & Fort-Collins Boxelder are no longer reporting COVID Viral Copies to CDPHE. Due to their absence, a new regression model was developed, including only the utilities that are still reporting through the program.  This new model actually has a slightly better correlation (.9677 vs .9662)  with the 7 day average Cases, and a slightly higher r-squared (.9365 vs .9335), meaning this model is slightly more accurate than the original model, depite relying on two less utilities.  All figures in the graph above now reflect the revised model. 

The above dashboard uses the COVID copies measured in Colorado Wastewater to estimate the actual number of cases of COVID occurring in the state at the time of the most recent wastewater data report.  It uses data from 20 Wastewater Utilities in the state of Colorado,  who have reported wastewater viral copies since their start date, mostly August 2020, with one being added in Occtober 2020. The included wastewater utilities are  Aurora, Berthoud, Boulder, Broomfield, CO Springs - JD Phillips, CO Springs - Las Vegas, Fort Collins - Boxelder, Fort Collins - Drake, Fort Collins - Mulberry, Greeley, Longmont, Louisville, Loveland, Metro WW - Clear Creek, Metro WW - Platte/Central, Pueblo, South Adams County, South Fort Collins, South Platte, Wellington Water and Sewer. 

Data is updated weekly (usually on Saturday afternoon after 5pm).  

This is an independent project that relies on data using data produced by CDPHE and the CDC, but not affiliated with CDPHE or the CDC in any way.  The developer affirms that there are no conflicts associated with this work that affect the integrity of the work. 

Read all about this tool, its validity and development here: https://docs.google.com/document/d/e/2PACX-1vQWXO5zGeMa7uSq3wy-OKIQbybLgPI4lbtvK9UBwL0BDCTTeDHQ5n-JHuU7tG9IJyjQ_CRdk1ExCKiP/pub 

To see CDPHE's own summary wastewater data, please CLICK HERE (link updated 8/15/24)

This tool was built using data from the CDPHE COVID Wastewater tool, available here: https://cdphe.colorado.gov/covid-19/wastewater (link updated 8/15/2024). 

It compares the wastewater trends to case data from the CDPHE site, available here: https://cdphe.colorado.gov/covid-19/data (linked updated 8/15/2024)

And uses population data posted on the CDC NWSS available here: https://www.cdc.gov/nwss/reporting/index.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fhealthywater%2Fsurveillance%2Fwastewater-surveillance%2Fdata-reporting-analytics.html

Thank you to the many people who have made this data available, especially hardworking public health staff, wastewater workers, and scientists.