Wastewater Virus Levels Screensaver
The Wastewater Virus Levels screensaver ranks US jurisdictions by SARS-CoV-2 levels in wastewater, from the CDC's National Wastewater Surveillance System dataset on data.cdc.gov. Each state's number is the average of its treatment plants' latest site percentiles. It's free, needs an internet connection, and ESC exits.
How the Wastewater Virus Levels screensaver works
Your browser queries the CDC's NWSS dataset on data.cdc.gov (key-less, CORS-enabled Socrata API) hourly.
It first asks the dataset for its newest sample date, then pulls the last two weeks of reports relative to that — so the board shows whatever CDC has most recently published, even if reporting lags.
Each treatment plant reports a 0–100 percentile of its latest sample against that site's own history; the board averages sites per jurisdiction and ranks them.
Colors band the average: green low, amber elevated, red near historical highs.
A worked example
If Utah's plants average a percentile of 84 while another state's sit at 12, Utah tops the board in red — a hint that infections may be rising there before case counts show it. The site count next to each name tells you how much signal is behind the average. In Multi-view it pairs well with the other health boards.
Settings & tips
- Jurisdictions shown sets how many rows the ranking keeps (10–20).
- The header shows the newest sample date in the dataset — NWSS reporting can lag or pause, and the board shows that date honestly.
- States with only a site or two swing harder; check the per-row site count before reading too much into a rank.
Frequently asked questions
- What does the wastewater percentile mean?
- Each site's latest sample is scored 0–100 against that same site's history — 80+ means near that site's historical highs. People shed virus before they feel sick, so rising wastewater levels are an early-warning signal that can lead reported cases by days.
- Is this real CDC data?
- Yes — the CDC's public NWSS SARS-CoV-2 dataset on data.cdc.gov, queried directly and aggregated in your browser. Values are shown as published.
- Do I need an API key?
- No. The Socrata endpoint is public, key-less and CORS-enabled.
- Does it work offline?
- No — it needs an internet connection to query data.cdc.gov; offline it shows a short notice.
- Is it free?
- Yes — free, no download, in your browser.