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Wastewater (sewage) can be tested to detect traces of infectious diseases circulating in a community, even if people don’t have symptoms. You can use these data as an early warning that levels of infections may be increasing or decreasing in your community.
Wastewater COVID-19 State and Territory Trends
COVID-19 NWSS Wastewater Monitoring in the U.S.
This chart shows state trends of SARS-COV-2 viral activity levels in wastewater. For comparison, you can also see trends for the region (Midwest, South, Northeast, West) in which the state is located and the national trend.
This chart shows state trends over time of the levels of SARS-CoV-2 (the virus that causes COVID-19) activity levels present in samples of wastewater taken from sites across the United States, compared to the regional and national trends. Wastewater monitoring can detect viruses spreading from one person to another within a community earlier than clinical testing and before people who are sick go to their doctor or hospital. It can also detect infections without symptoms. If you see increased Wastewater Viral Activity Levels of SARS-CoV-2, it might indicate that there is a higher risk of infection. See how to protect yourself from respiratory viruses like COVID-19.
The Wastewater Viral Activity Level shows changes in SARS-CoV-2 virus levels in wastewater compared to the baseline level for each wastewater treatment plant. National, regional, and state data represent the median values across all wastewater treatment plants in the respective area. The Wastewater Viral Activity Levels are categorized into minimal, low, moderate, high, or very high as follows:
- Less than 1.5 – Minimal
- Greater than 1.5 and up to 3 – Low
- Greater than 3 and up to 4.5 – Moderate
- Greater than 4.5 and up to 8 – High
- Greater than 8 – Very High
For more information, see Data Methods.
When you select a state, the region line corresponds to the region that state belongs to. States and territories are grouped into the following U.S Census Bureau regions:
- West: Alaska, Arizona, California, Colorado, Guam, Hawaii, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, Wyoming (N=14)
- Midwest: Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, Wisconsin (N=12)
- Northeast: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Puerto Rico, Rhode Island, Vermont (N=10)
- South: Arkansas, Alabama, Delaware, District of Columbia, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, West Virginia (N=17)