Inorganic chemicals
Cyanide in U.S. tap water
50 public water systems across 12 U.S. states report Cyanide in their annual Consumer Confidence Report. 2 sit at or above the federal limit.
At or above the federal limit (2)
| Water system | Measured | vs. limit |
|---|---|---|
| Mcallen, TX 2024 annual report | 2024 ug/L | 10.1× the limit |
| Odessa, TX 2024 annual report | 200 ug/L | 1.0× the limit |
Within the federal limit (44)
| Water system | Measured |
|---|---|
| Midland, TX 2024 annual report | 146 ug/L |
| Mckinney, TX 2024 annual report | 28.5–128 ug/L |
| Mesquite, TX 2024 annual report | 128 ug/L |
| Jackson, MS 2024 annual report | 127 ug/L |
| League City, TX 2024 annual report | 120–120 ug/L |
| Lewisville, TX 2024 annual report | 99 ug/L |
| Lubbock, TX 2024 annual report | 84.7 ug/L |
| San Angelo, TX 2024 annual report | 84.2–84.2 ug/L |
| Corpus Christi, TX 2024 annual report | 79 ug/L |
| Dallas, TX 2024 annual report | 54 ug/L |
| Houston, TX 2023 annual report | 52.5 ug/L |
| Austin, TX 2024 annual report | 50 ug/L |
| Brownsville, TX 2024 annual report | 50 ug/L |
| Georgetown, TX 2024 annual report | 42.7 ug/L |
| Fort Worth, TX 2024 annual report | 22.6 ug/L |
| Laredo, TX 2024 annual report | 0–20 ug/L |
| New Braunfels, TX 2024 annual report | 20 ug/L |
| Jacksonville, FL 2024 annual report | 0–11 ug/L |
| Norfolk, VA 2023 annual report | 0.011 mg/L |
| Edmond, OK 2024 annual report | 0–8.4 ug/L |
| Salt Lake City, UT 2024 annual report | 0–6 |
| St George, UT 2024 annual report | 0–5.4 ug/L |
| Tallahassee, FL 2024 annual report | 0–5.2 ug/L |
| Clarksville, TN 2024 annual report | 2.8 ug/L |
| Joliet, IL 2024 annual report | 2.8 ug/L |
| West Valley City, UT 2024 annual report | 0.5 ug/L |
| Birmingham, AL 2024 annual report | Not detected |
| City of Hampton, VA 2024 annual report | Not detected ug/L |
| City of Newport News, VA 2025 annual report | Not detected ug/L |
| City of Poquoson, VA 2025 annual report | Not detected mg/L |
| City of Poquoson, VA 2024 annual report | Not detected ug/L |
| Cleveland, OH 2024 annual report | Not detected |
| Columbus, OH 2025 annual report | Not detected |
| Hampton, VA 2025 annual report | Not detected mg/L |
| High Point, NC 2024 annual report | Not detected ug/L |
| James City County, VA 2025 annual report | Not detected ug/L |
| James City County, VA 2024 annual report | Not detected mg/L |
| Mobile, AL 2024 annual report | Not detected |
| Montgomery, AL 2024 annual report | Not detected |
| Nashville, TN 2023 annual report | Not detected |
| Newport News, VA 2024 annual report | Not detected mg/L |
| Pomona, CA 2024 annual report | Not detected ug/L |
| York County, VA 2024 annual report | Not detected mg/L |
| York County, VA 2025 annual report | Not detected mg/L |
Frequently asked
+What is Cyanide?
Cyanide is a contaminant some U.S. public water utilities measure and report in their annual Consumer Confidence Report.
+What is the federal limit for Cyanide in drinking water?
The federal MCL for Cyanide is 200 ug/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 Cyanide over the federal limit?
2 of the 50 public water systems on The Water Map report Cyanide at or above its federal limit, spanning 12 U.S. states. The full list is on this page.
+How can I check if Cyanide 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 Cyanide.