Microbial
Escherichia coli (E. coli) in U.S. tap water
591 public water systems across 20 U.S. states report Escherichia coli (E. coli) in their annual Consumer Confidence Report. None currently sit at or above the federal limit.
What it is
Escherichia coli — bacteria found in the gut of humans and animals.
Why it's regulated
Its presence in drinking water indicates fecal contamination and a real risk of waterborne illness.
Within the federal limit (542)
Showing 50 of 542. The full list is in the JSON API.
Frequently asked
+What is Escherichia coli (E. coli)?
Escherichia coli — bacteria found in the gut of humans and animals. Its presence in drinking water indicates fecal contamination and a real risk of waterborne illness.
+What is the federal limit for Escherichia coli (E. coli) in drinking water?
The federal MCLG for Escherichia coli (E. coli) is 0 . 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 Escherichia coli (E. coli) over the federal limit?
Zero of the 591 public water systems in The Water Map dataset currently report Escherichia coli (E. coli) at or above its federal limit.
+How can I check if Escherichia coli (E. coli) 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 Escherichia coli (E. coli).
See Escherichia coli (E. coli) on the map
Color-coded by status across the whole country.
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