Physical & aggregate
TOC in U.S. tap water
443 public water systems across 37 U.S. states report TOC in their annual Consumer Confidence Report. None currently sit at or above the federal limit.
What it is
Total organic carbon — a measure of organic material dissolved in the water.
Why it's regulated
Not harmful itself, but it is the raw material that forms disinfection byproducts; removal is a treatment requirement.
Within the federal limit (1)
| Water system | Measured |
|---|---|
| Crestview Mutual Water Co — Camarillo, Ca, CA 2023 annual report | Not detected mg/L |
Frequently asked
+What is TOC?
Total organic carbon — a measure of organic material dissolved in the water. Not harmful itself, but it is the raw material that forms disinfection byproducts; removal is a treatment requirement.
+What is the federal limit for TOC in drinking water?
The federal Treatment technique for TOC is 1 . The EPA enforces this against the regulated reporting statistic (typically a running annual average or 90th percentile), not a single-sample spike.
+How many U.S. water systems have TOC over the federal limit?
Zero of the 443 public water systems in The Water Map dataset currently report TOC at or above its federal limit.
+How can I check if TOC is in my city's tap water?
Search your city on The Water Map (https://www.thewatermap.com/) or browse the list on this page. Every U.S. public water utility is required to publish an annual Consumer Confidence Report that lists every contaminant it measured, including TOC.