Metals
Copper in U.S. tap water
1,346 public water systems across 44 U.S. states report Copper in their annual Consumer Confidence Report. 8 sit at or above the federal limit.
What it is
A metal that enters water from corroding household plumbing.
Why it's regulated
Short-term exposure causes stomach distress; long-term exposure can damage the liver and kidneys.
At or above the federal limit (8)
| Water system | Measured | vs. limit |
|---|---|---|
| Casa Dulce Estates — Agua Dulce, Ca, CA 2021 annual report | 2 mg/L | 1.5× the limit |
| Atascadero State Hospital — Atascadero, Ca, CA 2022 annual report | 1.7 mg/L | 1.3× the limit |
| Gramercy, MD 2024 annual report | 1.69 mg/L | 1.3× the limit |
| White Fence Farms Mwc No.3 — Lancaster, Ca, CA 2021 annual report | 1.5 mg/L | 1.2× the limit |
| Humboldt C.s.d. — Cutten, Ca, CA 2023 annual report | 1.3 mg/L | 1.0× the limit |
| Salt Lake City, UT 2024 annual report | 1.3 mg/L | 1.0× the limit |
| South Montebello Irrigation Dist. — Montebello, Ca, CA 2020 annual report | 1.3 mg/L | 1.0× the limit |
| Western MWD — Riverside, Ca, CA 2023 annual report | 1.3 mg/L | 1.0× the limit |
Approaching the limit (14)
| Water system | Measured | vs. limit |
|---|---|---|
| Alpine Water Users Association — Twin Peaks, Ca, CA 2023 annual report | 1.2 mg/L | 0.9× the limit |
| Los Angeles Cwwd 21-kagel Canyon — Alhambra, Ca, CA 2021 annual report | 1.2 mg/L | 0.9× the limit |
| Los Angeles Cwwd 21-kagel Canyon — Alhambra, Ca, CA 2020 annual report | 1.2 mg/L | 0.9× the limit |
| Pico Rivera - City, Water Dept. — Pico Rivera, Ca, CA 2023 annual report | 1.2 mg/L | 0.9× the limit |
| Pico Rivera - City, Water Dept. — Pico Rivera, Ca, CA 2021 annual report | 1.2 mg/L | 0.9× the limit |
| Pico Rivera - City, Water Dept. — Pico Rivera, Ca, CA 2022 annual report | 1.2 mg/L | 0.9× the limit |
| Arcata, City of — Arcata, Ca, CA 2023 annual report | 1.1 mg/L | 0.8× the limit |
| Blythe - City of — Blythe, Ca, CA 2022 annual report | 1.1 mg/L | 0.8× the limit |
| City of Buellton Water Division — Buellton, Ca, CA 2023 annual report | 1.1 mg/L | 0.8× the limit |
| Rockford, IL 2024 annual report | 1.1 mg/L | 0.8× the limit |
| San Miguelito Mwc — Avila Beach, Ca, CA 2023 annual report | 1.1 mg/L | 0.8× the limit |
| Town of Accident, MD 2024 annual report | 19–1100 ug/L | 0.8× the limit |
| Vineyard Ave Estates Mwc — Oxnard, Ca, CA 2022 annual report | 1.1 mg/L | 0.8× the limit |
| Jacksonville, FL 2024 annual report | 1.04 mg/L | 0.8× the limit |
Within the federal limit (1305)
Showing 50 of 1305. The full list is in the JSON API.
Frequently asked
+What is Copper?
A metal that enters water from corroding household plumbing. Short-term exposure causes stomach distress; long-term exposure can damage the liver and kidneys.
+What is the federal limit for Copper in drinking water?
The federal MCLG for Copper is 1.3 mg/L. 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 Copper over the federal limit?
8 of the 1346 public water systems on The Water Map report Copper at or above its federal limit, spanning 44 U.S. states. The full list is on this page.
+How can I check if Copper 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 Copper.