What was found in Piedmont'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 | 623 µg/L 6.2% of the EPA limit 10000 µg/L Main supplier: NORTHDALE SANITARY DISTRICT · 1,075 people · 2019
Highest in the city: 9900 µg/L — BESTGEN ADDITION WATER COMPANY · 73 people · 2019 | 15/27 | SYR4 |
| Fluoride | 1600 µg/L 40% of the EPA limit 4000 µg/L Highest in the city: RIMROCK HIGHLAND ESTATES COMM ASSOC · 66 people · 2017 | 19/27 | SYR4 |
| Copper | 281.8 µg/L 22% of the EPA limit 1300 µg/L Main supplier: NORTHDALE SANITARY DISTRICT · 1,075 people · 2018
Highest in the city: 607 µg/L — BESTGEN ADDITION WATER COMPANY · 73 people · 2018 | 25/27 | SYR4 |
| Barium | 397 µg/L 20% of the EPA limit 2000 µg/L Main supplier: NORTHDALE SANITARY DISTRICT · 1,075 people · 2012
Highest in the city: 533.7 µg/L — WESTBERRY TRAILS WATER USERS ASSOC · 155 people · 2018 | 19/27 | SYR4 |
| TTHM | 82.3 µg/L 103% of the EPA limit, at the 95th percentile of samples — 80 µg/L Highest in the city: SHERIDAN LAKE HIGHLANDS, INC. · 85 people · 2019 | 14/27 | SYR4 |
| Total Haloacetic Acids (HAA5) | 67.06 µg/L 112% of the EPA limit, at the 95th percentile of samples — 60 µg/L Highest in the city: SHERIDAN LAKE HIGHLANDS, INC. · 85 people · 2019 | 7/27 | SYR4 |
| Selenium | 17 µg/L 34% of the EPA limit 50 µg/L Highest in the city: RIMROCK HIGHLAND ESTATES COMM ASSOC · 66 people · 2017 | 3/27 | SYR4 |
| Gross Alpha, Excl. Radon And U | 6.39 pCi/L 43% of the EPA limit 15 pCi/L Main supplier: NORTHDALE SANITARY DISTRICT · 1,075 people · 2018
Highest in the city: 13.5 pCi/L — AUTUMN MEADOWS SANITARY DISTRICT · 49 people · 2019 | 16/27 | SYR4 |
| Combined Uranium | 11 µg/L 37% of the EPA limit 30 µg/L Highest in the city: TIMBERWOOD PARK ESTATES · 283 people · 2019 | 2/27 | SYR4 |
| Lead | 4.1 µg/L 27% of the EPA limit 15 µg/L Main supplier: NORTHDALE SANITARY DISTRICT · 1,075 people · 2018
Highest in the city: 10 µg/L — PIEDMONT · 971 people · 2019 | 25/27 | SYR4 |
| Arsenic | 6 µg/L 60% of the EPA limit 10 µg/L Main supplier: NORTHDALE SANITARY DISTRICT · 1,075 people · 2019
Highest in the city: 8 µg/L — BLUCKSBERG MOUNTAIN #2 · 333 people · 2018 | 4/27 | SYR4 |
| Lead | 0.0020 mg/L 13% of the EPA limit 0.0150 mg/L Main supplier: NORTHDALE SANITARY DISTRICT · 1,075 people · 2024
Highest in the city: 0.0090 mg/L — BLUCKSBERG MOUNTAIN #2 · 333 people · 2025 | 27/27 | LCR |
Water suppliers serving Piedmont
Frequently asked questions about Piedmont tap water
Is Piedmont tap water safe to drink?
EPA testing detected 12 contaminants in the water serving Piedmont. 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 Piedmont?
27 public water suppliers report drinking-water monitoring for Piedmont, South Dakota to the EPA. Each is listed above with its population served.
What contaminants are in Piedmont's water?
The contaminants EPA monitoring detected in Piedmont include Nitrate, Fluoride, Copper, Barium, TTHM. 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.