What was found in Moses Lake's water
The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 5650 µg/L 56% of the EPA limit 10000 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 13500 µg/L — PARKER SPRING ACRES WATER ASSOC · 255 people · 2019 | 21/25 | SYR4 |
| Nitrate-Nitrite | 5598 µg/L 56% of the EPA limit 10000 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 13335 µg/L — PARKER SPRING ACRES WATER ASSOC · 255 people · 2019 | 20/25 | SYR4 |
| Fluoride | 2819.5 µg/L 70% of the EPA limit 4000 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019 | 21/25 | SYR4 |
| Nitrite | 440 µg/L 44% of the EPA limit 1000 µg/L Highest in the city: FIRST POTHOLES WATER USERS ASSN · 90 people · 2019 | 2/25 | SYR4 |
| Copper | 24.603 µg/L 1.9% of the EPA limit 1300 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 229.27 µg/L — GROVE TERRACE MHP TWO LLC · 220 people · 2019 | 16/25 | SYR4 |
| Barium | 54.78 µg/L 2.7% of the EPA limit 2000 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 69.86 µg/L — GROVE TERRACE MHP TWO LLC · 220 people · 2019 | 16/25 | SYR4 |
| TTHM | 15.42 µg/L 19% of the EPA limit 80 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 41.8 µg/L — ADMIRAL WATER USERS ASSN · 74 people · 2017 | 11/25 | SYR4 |
| Lithium | 35.6 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2025 | 1/25 | UCMR-5 |
| Chloroform | 2.96 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 33.74 µg/L — ADMIRAL WATER USERS ASSN · 74 people · 2018 | 10/25 | SYR4 |
| Chromium | 1.7175 µg/L 1.7% of the EPA limit 100 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 13.7 µg/L — Westshore Water Company · 153 people · 2018 | 10/25 | SYR4 |
| Total Haloacetic Acids (HAA5) | 3.74 µg/L 6.2% of the EPA limit 60 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2018
Highest in the city: 12.275 µg/L — GROVE TERRACE MHP TWO LLC · 220 people · 2018 | 9/25 | SYR4 |
| Bromoform | 11.25 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019 | 9/25 | SYR4 |
| Lead | 8.389 µg/L 56% of the EPA limit 15 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019 | 6/25 | SYR4 |
| Dibromochloromethane | 3.34 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 7.36 µg/L — MARINE VIEW HOME OWNERS ASSN · 87 people · 2017 | 11/25 | SYR4 |
| Dichloroacetic Acid | 2.735 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 7 µg/L — GROVE TERRACE MHP TWO LLC · 220 people · 2018 | 7/25 | SYR4 |
| Arsenic | 3.478 µg/L 35% of the EPA limit 10 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 6.54 µg/L — FIRST POTHOLES WATER USERS ASSN · 90 people · 2019 | 19/25 | SYR4 |
| Bromodichloromethane | 2.385 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 6.52 µg/L — GROVE TERRACE MHP TWO LLC · 220 people · 2018 | 10/25 | SYR4 |
| Trichloroacetic Acid | 1.7 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 5.5685 µg/L — GROVE TERRACE MHP TWO LLC · 220 people · 2018 | 4/25 | SYR4 |
| Trichloroethylene | 4.878 µg/L 98% of the EPA limit 5 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019 | 2/25 | SYR4 |
| Combined Radium (-226 And -228) | 4.77 pCi/L 95% of the EPA limit 5 pCi/L Highest in the city: GROVE TERRACE MHP TWO LLC · 220 people · 2015 | 1/25 | SYR4 |
| Dibromoacetic Acid | 2.36 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 4.48 µg/L — MT VIEW WATER SYSTEM · 44 people · 2019 | 7/25 | SYR4 |
| 1,1,2-Trichloroethane | 3.9 µg/L 78% of the EPA limit 5 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019 | 1/25 | SYR4 |
| Selenium | 1.062 µg/L 2.1% of the EPA limit 50 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 2 µg/L — HILLCREST WATER USERS ASSN · 300 people · 2019 | 5/25 | SYR4 |
| Thallium, Total | 1.08 µg/L 54% of the EPA limit 2 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 1.1215 µg/L — PARKER SPRING ACRES WATER ASSOC · 255 people · 2016 | 6/25 | SYR4 |
| Mercury | 0.9300 µg/L 47% of the EPA limit 2 µg/L Highest in the city: SUN DESERT INC · 27 people · 2018 | 1/25 | SYR4 |
| cis-1,2-Dichloroethylene | 0.7080 µg/L 1% of the EPA limit 70 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019 | 1/25 | SYR4 |
| 1,2-Dichloropropane | 0.6000 µg/L 12% of the EPA limit 5 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019 | 1/25 | SYR4 |
| Antimony, Total | 0.2930 µg/L 4.9% of the EPA limit 6 µg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2019
Highest in the city: 0.3100 µg/L — SKYLINE ACRES INC · 151 people · 2016 | 4/25 | SYR4 |
| Picloram | 0.2050 µg/L 0% of the EPA limit 500 µg/L Highest in the city: SILVER SANDS CONDO WATER · 37 people · 2019 | 1/25 | SYR4 |
| Cadmium | 0.1400 µg/L 2.8% of the EPA limit 5 µg/L Highest in the city: GROVE TERRACE MHP TWO LLC · 220 people · 2019 | 1/25 | SYR4 |
| Atrazine | 0.0585 µg/L 2% of the EPA limit 3 µg/L Highest in the city: HILLCREST WATER USERS ASSN · 300 people · 2018 | 2/25 | SYR4 |
| PFHXS | 0.0541 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2025 | 1/25 | UCMR-5 |
| PFOS | 0.0522 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2025 | 1/25 | UCMR-5 |
| Lead | 0.0032 mg/L 21% of the EPA limit 0.0150 mg/L Main supplier: MOSES LAKE CITY OF · 32,428 people · 2023
Highest in the city: 0.0131 mg/L — HILLCREST WATER USERS ASSN · 300 people · 2025 | 22/25 | LCR |
| Simazine | 0.0100 µg/L 0.3% of the EPA limit 4 µg/L Highest in the city: HILLCREST WATER USERS ASSN · 300 people · 2018 | 1/25 | SYR4 |
| Pfhxa | 0.0073 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2025 | 1/25 | UCMR-5 |
| Pfpes | 0.0053 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2025 | 1/25 | UCMR-5 |
| PFBS | 0.0044 µg/L No EPA limit set Main supplier: MOSES LAKE CITY OF · 32,428 people · 2025 | 1/25 | UCMR-5 |
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the 95th percentile of the
system's samples — over 100% is worth reading, but is not by itself a
violation.
Formal violations are listed separately.
These are the utilities' own EPA-reported results, not a city-wide
average. A detection means the lab measured the
substance — it isn't the same as exceeding a legal limit. Hover a source
tag to see the EPA program and years behind each figure.
Water suppliers serving Moses Lake
Frequently asked questions about Moses Lake tap water
Is Moses Lake tap water safe to drink?
EPA testing detected 38 contaminants in the water serving Moses Lake. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.
How many water suppliers serve Moses Lake?
25 public water suppliers report drinking-water monitoring for Moses Lake, Washington to the EPA. Each is listed above with its population served.
What contaminants are in Moses Lake's water?
The contaminants EPA monitoring detected in Moses Lake include Nitrate, Nitrate-Nitrite, Fluoride, Nitrite, Copper. The full list, with the level at the main supplier and the data source, is in the table above.
Where does this data come from?
Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.