What was found in ZIP 57223
The level at this ZIP's main supplier, the highest level anywhere in it, the EPA limit for each, and where the figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 3200 µg/L 32% of the EPA limit 10000 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2019
Highest in the ZIP: 7300 µg/L — CASTLEWOOD · 698 people · 2019 | 2/2 | SYR4 |
| Copper | 797.5 µg/L 61% of the EPA limit 1300 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2019
Highest in the ZIP: 2160 µg/L — CASTLEWOOD · 698 people · 2019 | 2/2 | SYR4 |
| TTHM | 108.9 µg/L 136% of the EPA limit, at the 95th percentile of samples — 80 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2019 | 2/2 | SYR4 |
| Barium | 103.275 µg/L 5.2% of the EPA limit 2000 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2013 | 1/2 | SYR4 |
| Total Haloacetic Acids (HAA5) | 80.04 µg/L 133% of the EPA limit, at the 95th percentile of samples — 60 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2019 | 2/2 | SYR4 |
| Lithium | 52.2 µg/L No EPA limit set Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2023 | 1/2 | UCMR-5 |
| Gross Alpha, Excl. Radon And U | 6.735 pCi/L 45% of the EPA limit 15 pCi/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2019
Highest in the ZIP: 12.935 pCi/L — CASTLEWOOD · 698 people · 2017 | 2/2 | SYR4 |
| Chromium | 9.66 µg/L 9.7% of the EPA limit 100 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2013 | 1/2 | SYR4 |
| Lead | 6.24 µg/L 42% of the EPA limit 15 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2019 | 2/2 | SYR4 |
| Selenium | 2.78 µg/L 5.6% of the EPA limit 50 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2013 | 1/2 | SYR4 |
| Arsenic | 2 µg/L 20% of the EPA limit 10 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2013 | 1/2 | SYR4 |
| Antimony, Total | 0.3900 µg/L 6.5% of the EPA limit 6 µg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2013 | 1/2 | SYR4 |
| Lead | 0.0040 mg/L 27% of the EPA limit 0.0150 mg/L Main supplier: SIOUX RURAL WATER SYSTEM · 4,280 people · 2025 | 2/2 | LCR |
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.
Water suppliers serving ZIP 57223
| Supplier | State | Population served |
|---|---|---|
| SIOUX RURAL WATER SYSTEM | SD | 4,280 |
| CASTLEWOOD | SD | 698 |
Frequently asked questions about ZIP 57223 tap water
Is the tap water in ZIP 57223 safe to drink?
EPA testing detected 13 contaminants across the water suppliers serving ZIP 57223. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and your utility's annual Consumer Confidence Report for the official status.
Which water suppliers serve ZIP 57223?
2 public water suppliers report EPA drinking-water monitoring for ZIP 57223. Each is listed above with its population served.
What contaminants are in ZIP 57223's water?
EPA monitoring detected Nitrate, Copper, TTHM, Barium, Total Haloacetic Acids (HAA5), and others across this ZIP's suppliers. The full list with levels and sources is above.