Physical & aggregate
Turbidity in U.S. tap water
662 public water systems across 36 U.S. states report Turbidity in their annual Consumer Confidence Report. 105 sit at or above the federal limit.
662
systems measuring
105
over the limit
36
states represented
What it is
A measure of cloudiness from suspended particles in the water.
Why it's regulated
High turbidity can shelter microbes from disinfection; the EPA enforces it through a treatment-technique standard.
Federal limit1 NTU· Treatment technique
At or above the federal limit (105)
| Water system | Measured | vs. limit |
|---|---|---|
| Cedar Rapids, IA 2024 annual report | 99.99 NTU | 100.0× the limit |
| City of Robins, IA 2024 annual report | 99.99 NTU | 100.0× the limit |
| Glenbrook Cove Subdivision of Marion, IA 2024 annual report | 99.99 NTU | 100.0× the limit |
| Poweshiek Water Association, IA 2024 annual report | 99.99 NTU | 100.0× the limit |
| San Joaquin County - Lincoln Village — Stockton, Ca, CA 2023 annual report | 98.5 NTU | 98.5× the limit |
| Hamden, CT 2024 annual report | 0–98 NTU | 98.0× the limit |
| City of Hemet, CA 2024 annual report | 97 NTU | 97.0× the limit |
| City of Menifee, CA 2024 annual report | 97 NTU | 97.0× the limit |
| City of Murrieta, CA 2024 annual report | 97 NTU | 97.0× the limit |
| City of San Jacinto, CA 2024 annual report | 97 NTU | 97.0× the limit |
| East Valley Service Area, CA 2024 annual report | 97 NTU | 97.0× the limit |
| Mills Service Area, CA 2024 annual report | 97 NTU | 97.0× the limit |
| Moreno Valley, CA 2024 annual report | 97 NTU | 97.0× the limit |
| Oceanside, City of — Oceanside, Ca, CA 2023 annual report | 95 NTU | 95.0× the limit |
| West Palm Beach, FL 2024 annual report | 83.3 NTU | 83.3× the limit |
| Foothill Municipal Water Dist. — La Canada Flintridge, Ca, CA 2023 annual report | 0.5–16 NTU | 16.0× the limit |
| Fort Hunter Liggett — Fort Hunter Liggett, Ca, CA 2022 annual report | 11.48 NTU | 11.5× the limit |
| Albany, NY 2024 annual report | 0.08–9.28 NTU | 9.3× the limit |
| Valencia Heights Water Co. — West Covina, Ca, CA 2021 annual report | 0.28–7.2 NTU | 7.2× the limit |
| Cws - Kernville — San Jose, Ca, CA 2023 annual report | 0.19–5.7 NTU | 5.7× the limit |
| Lake Elizabeth Mutual Water Co. — Elizabeth Lake, Ca, CA 2022 annual report | 4.8 NTU | 4.8× the limit |
| Glendale, CA 2024 annual report | 4.6 NTU | 4.6× the limit |
| St. Helena, City of — St. Helena, Ca, CA 2023 annual report | 4.6 NTU | 4.6× the limit |
| Lake Elizabeth Mutual Water Co. — Elizabeth Lake, Ca, CA 2021 annual report | 4.4 NTU | 4.4× the limit |
| Glendora-city, Water Dept. — Glendora, Ca, CA 2020 annual report | 0–4.3 NTU | 4.3× the limit |
| Elsinore Valley MWD — Lake Elsinore, Ca, CA 2022 annual report | 0–2.5 NTU | 2.5× the limit |
| Lincoln Avenue Water Co. — Altadena, Ca, CA 2022 annual report | 2.3 NTU | 2.3× the limit |
| Whittier-city, Water Dept. — Whittier, Ca, CA 2022 annual report | 0–2.2 NTU | 2.2× the limit |
| Whittier-city, Water Dept. — Whittier, Ca, CA 2020 annual report | 0–2.2 NTU | 2.2× the limit |
| Whittier-city, Water Dept. — Whittier, Ca, CA 2021 annual report | 0–2.2 NTU | 2.2× the limit |
| Alameda County Water District — Fremont, Ca, CA 2023 annual report | 2.1 NTU | 2.1× the limit |
| City of San Jose - Nsj/alviso — San Jose, Ca, CA 2023 annual report | 2.1 NTU | 2.1× the limit |
| Nyc, NY 2023 annual report | 2.1 NTU | 2.1× the limit |
| Lemoore Naval Air Station — Lemoore, Ca, CA 2023 annual report | 2 NTU | 2.0× the limit |
| So. Cal. Edison Co.-santa Catalina — Avalon, Ca, CA 2021 annual report | 2 NTU | 2.0× the limit |
| Kent, WA 2024 annual report | 1.99 NTU | 2.0× the limit |
| Buffalo, NY 2023 annual report | 0.04–1.97 NTU | 2.0× the limit |
| Vallecitos Wd — San Marcos, Ca, CA 2023 annual report | 0.1–1.8 NTU | 1.8× the limit |
| West Valley Water District — Rialto, Ca, CA 2023 annual report | 1.8 NTU | 1.8× the limit |
| Portland, OR 2024 annual report | 0.22–1.65 NTU | 1.6× the limit |
| Kinneloa Irrigation Dist. — Pasadena, Ca, CA 2020 annual report | 0–1.6 NTU | 1.6× the limit |
| Santa Ynez River Water Cons. Dist. Id#1 — Santa Ynez, Ca, CA 2023 annual report | 0–1.6 NTU | 1.6× the limit |
| Solvang Water Division — Solvang, Ca, CA 2023 annual report | 0–1.6 NTU | 1.6× the limit |
| Yonkers, NY 2024 annual report | 1.5 NTU | 1.5× the limit |
| New Orleans, LA 2024 annual report | 0.03–1.44 NTU | 1.4× the limit |
| Glendora-city, Water Dept. — Glendora, Ca, CA 2023 annual report | 0–1.3 NTU | 1.3× the limit |
| Pomona, CA 2024 annual report | 0–1.3 NTU | 1.3× the limit |
| St George, UT 2024 annual report | 1.3 NTU | 1.3× the limit |
| City of Arcadia — Arcadia, Ca, CA 2020 annual report | 0–1.2 NTU | 1.2× the limit |
| City of Arcadia — Arcadia, Ca, CA 2021 annual report | 0–1.2 NTU | 1.2× the limit |
| La Canada Irrigation Dist. — La Canada, Ca, CA 2020 annual report | 1.2 NTU | 1.2× the limit |
| Paramount - City, Water Dept. — Paramount, Ca, CA 2021 annual report | 1.2 NTU | 1.2× the limit |
| Cabazon Water District — Cabazon, Ca, CA 2023 annual report | 0–1.1 NTU | 1.1× the limit |
| City of South Pasadena — South Pasadena, Ca, CA 2023 annual report | 0–1.1 NTU | 1.1× the limit |
| Inglewood, CA 2023 annual report | 1.1 NTU | 1.1× the limit |
| Paramount - City, Water Dept. — Paramount, Ca, CA 2020 annual report | 1.1 NTU | 1.1× the limit |
| Alpine Springs Mobile Home Park — Palmdale, Ca, CA 2020 annual report | 1 NTU | 1.0× the limit |
| Alpine Springs Mobile Home Park — Palmdale, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| Alpine Springs Mobile Home Park — Palmdale, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| Atascadero State Hospital — Atascadero, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| Cali Lake Rv Resort — Marina Del Ray, Ca, CA 2020 annual report | 1 NTU | 1.0× the limit |
| Calistoga, City of — Calistoga, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| City of Dos Palos — Dos Palos, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| City of La Palma — La Palma, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| City of Mountain House — Mountain House, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| City of Newport Beach — Newport Beach, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| City of Orange Cove — Orange Cove, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| City of Shasta Lake — Shasta Lake, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| Fenner Canyon Youth Conservation Camp — Valyermo, Ca, CA 2020 annual report | 1 NTU | 1.0× the limit |
| Foresthill Public Utility Dist — Foresthill, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Frisco, TX 2024 annual report | 1 NTU | 1.0× the limit |
| Green Valley Mwc — Green Valley Lake, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Heber Public Utility District — Heber, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Huron, City of — Huron, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Lake Elizabeth Mutual Water Co. — Elizabeth Lake, Ca, CA 2020 annual report | 1 NTU | 1.0× the limit |
| Lake Elizabeth Mutual Water Co. — Elizabeth Lake, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Lakeside Park Association — South Lake Tahoe, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Landale Mutual Water Company — Lancaster, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| Liberty Park Water Association — Huntington Beach, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| Llano Del Rio Water Company — Llano, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| Llano Del Rio Water Company — Llano, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| Llano Mutual Water Company — Llano, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| Los Angeles Residential Community Founda — Santa Clarita, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| Los Angeles Residential Community Founda — Santa Clarita, Ca, CA 2020 annual report | 1 NTU | 1.0× the limit |
| Los Angeles Residential Community Founda — Santa Clarita, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| Malaga County Water District — Fresno, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| Meadow Vista Cwd — Meadow Vista, Ca, CA 2024 annual report | 1 NTU | 1.0× the limit |
| Montara Water and Sanitary District — Montara, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| North Gualala Water Company — Gualala, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Nps-ash Mountain — Three Rivers, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Oak Grove Mobile Home Park — Bell Canyon, Ca, CA 2020 annual report | 1 NTU | 1.0× the limit |
| Oak Grove Mobile Home Park — Bell Canyon, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| Oak Grove Mobile Home Park — Bell Canyon, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| Phoenix, AZ 2025 annual report | 1 NTU | 1.0× the limit |
| Rivers End Trailer Park — Agoura Hills, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| Rivers End Trailer Park — Agoura Hills, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Rivers End Trailer Park — Agoura Hills, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| San Dieguito Wd — Encinitas, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Santa Nella County Water District — Santa Nella, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| Valhalla Water Association — Tujunga, Ca, CA 2020 annual report | 1 NTU | 1.0× the limit |
| Valhalla Water Association — Tujunga, Ca, CA 2022 annual report | 1 NTU | 1.0× the limit |
| White Fence Farms Mwc No. 1 — Palmdale, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| White Fence Farms Mwc No. 1 — Palmdale, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
| White Fence Farms Mwc No.3 — Lancaster, Ca, CA 2021 annual report | 1 NTU | 1.0× the limit |
| Winton Water & Sanitary Dist — Winton, Ca, CA 2023 annual report | 1 NTU | 1.0× the limit |
Approaching the limit (15)
| Water system | Measured | vs. limit |
|---|---|---|
| Paradise Irrigation District — Paradise, Ca, CA 2023 annual report | 0.99 NTU | 1.0× the limit |
| So. Cal. Edison Co.-santa Catalina — Avalon, Ca, CA 2023 annual report | 0.96 NTU | 1.0× the limit |
| Rowland Water District — Rowland Heights, Ca, CA 2023 annual report | 0.4–0.95 NTU | 0.9× the limit |
| City of Cupertino, CA 2024 annual report | 0.9 NTU | 0.9× the limit |
| Lakeside Wd — Lakeside, Ca, CA 2023 annual report | 0.03–0.9 NTU | 0.9× the limit |
| Paramount - City, Water Dept. — Paramount, Ca, CA 2022 annual report | 0.9 NTU | 0.9× the limit |
| San Jose, CA 2024 annual report | 0.9 NTU | 0.9× the limit |
| Torrance, CA 2024 annual report | 0.1–0.9 NTU | 0.9× the limit |
| Humboldt C.s.d. — Cutten, Ca, CA 2023 annual report | 0.81 NTU | 0.8× the limit |
| Beverly Hills-city, Water Dept. — Beverly Hills, Ca, CA 2020 annual report | 0–0.8 NTU | 0.8× the limit |
| Fort Bragg, City of — Fort Bragg, Ca, CA 2022 annual report | 0.8 NTU | 0.8× the limit |
| Glendora-city, Water Dept. — Glendora, Ca, CA 2021 annual report | 0–0.8 NTU | 0.8× the limit |
| Hilmar County Water District — Hilmar, Ca, CA 2023 annual report | 0.2–0.8 NTU | 0.8× the limit |
| Paramount - City, Water Dept. — Paramount, Ca, CA 2023 annual report | 0.8 NTU | 0.8× the limit |
| Pearland, TX 2024 annual report | 0.8 NTU | 0.8× the limit |
Within the federal limit (473)
Showing 50 of 473. The full list is in the JSON API.
Frequently asked
+What is Turbidity?
A measure of cloudiness from suspended particles in the water. High turbidity can shelter microbes from disinfection; the EPA enforces it through a treatment-technique standard.
+What is the federal limit for Turbidity in drinking water?
The federal Treatment technique for Turbidity is 1 NTU. 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 Turbidity over the federal limit?
105 of the 662 public water systems on The Water Map report Turbidity at or above its federal limit, spanning 36 U.S. states. The full list is on this page.
+How can I check if Turbidity 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 Turbidity.