Metals
Lithium in U.S. tap water
125 public water systems across 26 U.S. states report Lithium in their annual Consumer Confidence Report. 20 sit at or above the federal limit.
What it is
A naturally occurring element found in some groundwater.
Why it's regulated
No enforceable federal limit; on the EPA contaminant candidate list for further study.
At or above the federal limit (20)
| Water system | Measured | vs. limit |
|---|---|---|
| New Braunfels, TX 2024 annual report | 2024 | 179.1× the limit |
| Chandler, AZ 2024 annual report | 190.44 ug/L | 21.2× the limit |
| Tempe, AZ 2024 annual report | 141 ug/L | 15.7× the limit |
| Omaha, NE 2024 annual report | 102 | 11.3× the limit |
| Glendale, AZ 2024 annual report | 61 ug/L | 6.8× the limit |
| San Diego, CA 2023 annual report | 49.5 ug/L | 5.5× the limit |
| Santa Clarita, CA 2024 annual report | 46 ug/L | 5.1× the limit |
| Lubbock, TX 2024 annual report | 41.48 ug/L | 4.6× the limit |
| Pomona, CA 2024 annual report | 32–40 ug/L | 4.0× the limit |
| Albuquerque, NM 2024 annual report | 34 | 3.4× the limit |
| Chula Vista Otay, CA 2024 annual report | 0–28.9 ug/L | 3.2× the limit |
| El Cajon, CA 2024 annual report | 28 ug/L | 2.8× the limit |
| Escondido, CA 2024 annual report | 23 ug/L | 2.6× the limit |
| Olathe, KS 2024 annual report | 20.7 ug/L | 2.3× the limit |
| Pasadena, CA 2023 annual report | 16 ug/L | 1.8× the limit |
| San Antonio, TX 2023 annual report | 12.82 ug/L | 1.4× the limit |
| Rochester, MN 2025 annual report | 0–10.8 | 1.1× the limit |
| Centennial, CO 2023 annual report | 9.23 ug/L | 1.0× the limit |
| Denver, CO 2023 annual report | 9.23 ug/L | 1.0× the limit |
| Lakewood, CO 2024 annual report | 9.23 ug/L | 1.0× the limit |
Approaching the limit (2)
| Water system | Measured | vs. limit |
|---|---|---|
| Evansville, IN 2024 annual report | 8.3 | 0.9× the limit |
| Tracy, CA 2024 annual report | 8 | 0.9× the limit |
Within the federal limit (7)
| Water system | Measured |
|---|---|
| Dallas, TX 2024 annual report | Not detected ng/L |
| Dearborn, MI 2024 annual report | Not detected ug/L |
| Fairfield, CA 2024 annual report | Not detected |
| Freedom District, MD 2024 annual report | Not detected ug/L |
| Salem, OR 2023 annual report | Not detected ug/L |
| Suffolk, VA 2024 annual report | Not detected ug/L |
| Vallejo, CA 2024 annual report | Not detected ug/L |
Frequently asked
+What is Lithium?
A naturally occurring element found in some groundwater. No enforceable federal limit; on the EPA contaminant candidate list for further study.
+What is the federal limit for Lithium in drinking water?
The federal MCL for Lithium is 10 . 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 Lithium over the federal limit?
20 of the 125 public water systems on The Water Map report Lithium at or above its federal limit, spanning 26 U.S. states. The full list is on this page.
+How can I check if Lithium 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 Lithium.