Metals
Barium in U.S. tap water
813 public water systems across 41 U.S. states report Barium in their annual Consumer Confidence Report. 4 sit at or above the federal limit.
What it is
A metal from erosion of natural deposits and industrial discharge.
Why it's regulated
Long-term exposure above the federal limit can raise blood pressure.
At or above the federal limit (4)
| Water system | Measured | vs. limit |
|---|---|---|
| Winton Water & Sanitary Dist — Winton, Ca, CA 2023 annual report | 5 mg/L | 2.5× the limit |
| St Petersburg, FL 2024 annual report | 4 mg/L | 2.0× the limit |
| Esparto C.s.d. — Esparto, Ca, CA 2023 annual report | 0–2 mg/L | 1.0× the limit |
| Frisco, TX 2024 annual report | 2 mg/L | 1.0× the limit |
Within the federal limit (809)
| Water system | Measured |
|---|---|
| Arlington, TX 2024 annual report | 0.63 mg/L |
| Whittier-city, Water Dept. — Whittier, Ca, CA 2020 annual report | 0–0.59 mg/L |
| Whittier-city, Water Dept. — Whittier, Ca, CA 2021 annual report | 0–0.59 mg/L |
| Commerce-city, Water Dept. — San Jose, Ca, CA 2021 annual report | 0.54 mg/L |
| Norman, OK 2024 annual report | 0.53 mg/L |
| Shafter, City of — Shafter, Ca, CA 2022 annual report | 0–0.492 mg/L |
| Peoria, AZ 2024 annual report | 0.49 mg/L |
| City of Lathrop — Lathrop, Ca, CA 2023 annual report | 0.4 mg/L |
| Riverstone/rootcreek Water District — Fresno, Ca, CA 2023 annual report | 0.15–0.39 mg/L |
| Madera Co Md10a-madera Ranchos — Madera, Ca, CA 2023 annual report | 0.25–0.38 mg/L |
| Pearland, TX 2024 annual report | 0.357 mg/L |
| Fishers, IN 2024 annual report | 0.35 mg/L |
| Indianapolis, IN 2024 annual report | 0.35 mg/L |
| Morgan County, IN 2024 annual report | 0.35 mg/L |
| Westfield, IN 2024 annual report | 0.35 mg/L |
| Benedictine School, MD 2024 annual report | 0.34 mg/L |
| City of Paso Robles Water Division — Paso Robles, Ca, CA 2023 annual report | 0–0.33 mg/L |
| Rio Cosumnes Correctional Center [sws] — Sacramento, Ca, CA 2023 annual report | 0–0.33 mg/L |
| Carmichael Water District — Carmichael, Ca, CA 2023 annual report | 0.32 mg/L |
| Indianapolis, IN 2023 annual report | 0.32 mg/L |
| Indianapolis, IN 2023 annual report | 0.32 mg/L |
| Morgan County, IN 2023 annual report | 0.32 mg/L |
| Westfield, IN 2023 annual report | 0.32 mg/L |
| Beantown Woodley, MD 2024 annual report | 0.315 mg/L |
| Glendora-city, Water Dept. — Glendora, Ca, CA 2023 annual report | 0–0.31 mg/L |
| Glendora-city, Water Dept. — Glendora, Ca, CA 2022 annual report | 0–0.31 mg/L |
| Glendora-city, Water Dept. — Glendora, Ca, CA 2021 annual report | 0–0.3 mg/L |
| Houston, TX 2023 annual report | 0.3 mg/L |
| Jersey City, NJ 2024 annual report | 0.293 mg/L |
| St George, UT 2024 annual report | 287 ug/L |
| Cedarville Mhp, MD 2024 annual report | 0.276 mg/L |
| Aromas Water District — Aromas, Ca, CA 2023 annual report | 0.14–0.26 mg/L |
| Glendora-city, Water Dept. — Glendora, Ca, CA 2020 annual report | 0–0.26 mg/L |
| Hamden, CT 2024 annual report | 0.004–0.26 mg/L |
| Lakeside Wd — Lakeside, Ca, CA 2023 annual report | 150–259 ug/L |
| Gonzales, City of — Gonzales, Ca, CA 2022 annual report | 0.1–0.25 mg/L |
| Lafayette, LA 2024 annual report | 0.25 mg/L |
| Edmond, OK 2024 annual report | 0.115–0.242 mg/L |
| Nuevo Water Company — Nuevo, Ca, CA 2022 annual report | 0.24 mg/L |
| San Joaquin County-mokelumne Acres — Stockton, Ca, CA 2023 annual report | 0–239 ug/L |
| Cal Am - Meadowbrook — Sacramento, Ca, CA 2023 annual report | 0.23 mg/L |
| City of Merced — Merced, Ca, CA 2023 annual report | 0.23 mg/L |
| Los Angeles Cwwd 36-val Verde — Alhambra, Ca, CA 2023 annual report | 0.23 mg/L |
| Cambria Comm Services Dist — Cambria, Ca, CA 2023 annual report | 0.13–0.22 mg/L |
| San Angelo, TX 2024 annual report | 0.22 mg/L |
| Baton Rouge, LA 2024 annual report | 0.21 mg/L |
| Exeter, City of — Exeter, Ca, CA 2023 annual report | 0.065–0.21 mg/L |
| Firebaugh City — Firebaugh, Ca, CA 2023 annual report | 0.05–0.21 mg/L |
| City of Hemet, CA 2024 annual report | 209 ug/L |
| City of Menifee, CA 2024 annual report | 209 ug/L |
Showing 50 of 809. The full list is in the JSON API.
Frequently asked
+What is Barium?
A metal from erosion of natural deposits and industrial discharge. Long-term exposure above the federal limit can raise blood pressure.
+What is the federal limit for Barium in drinking water?
The federal MCL for Barium is 2 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 Barium over the federal limit?
4 of the 813 public water systems on The Water Map report Barium at or above its federal limit, spanning 41 U.S. states. The full list is on this page.
+How can I check if Barium 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 Barium.