What was found in ZIP 57701
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 | 1443.5 µg/L 14% of the EPA limit 10000 µg/L Main supplier: RAPID CITY · 72,009 people · 2019
Highest in the ZIP: 7760 µg/L — RIMROCK HEIGHTS HOMEOWNERS ASSOCIATI · 35 people · 2019 | 6/11 | SYR4 |
| Fluoride | 500 µg/L 13% of the EPA limit 4000 µg/L Highest in the ZIP: CEDAR GULCH 2 · 40 people · 2018 | 7/11 | SYR4 |
| Barium | 134.5 µg/L 6.7% of the EPA limit 2000 µg/L Main supplier: RAPID CITY · 72,009 people · 2019
Highest in the ZIP: 462 µg/L — WESTON HEIGHTS HOMEOWNERS ASSOCIATIO · 412 people · 2013 | 8/11 | SYR4 |
| Copper | 311.7 µg/L 24% of the EPA limit 1300 µg/L Main supplier: RAPID CITY · 72,009 people · 2018 | 10/11 | SYR4 |
| Nitrite | 200 µg/L 20% of the EPA limit 1000 µg/L Main supplier: RAPID CITY · 72,009 people · 2018 | 1/11 | SYR4 |
| TTHM | 28.85 µg/L 36% of the EPA limit 80 µg/L Main supplier: RAPID CITY · 72,009 people · 2019 | 5/11 | SYR4 |
| Total Haloacetic Acids (HAA5) | 18.45 µg/L 31% of the EPA limit 60 µg/L Main supplier: RAPID CITY · 72,009 people · 2019 | 1/11 | SYR4 |
| Selenium | 18.25 µg/L 37% of the EPA limit 50 µg/L Highest in the ZIP: BOX ELDER · 14,000 people · 2017 | 2/11 | SYR4 |
| Gross Alpha, Excl. Radon And U | 6.594 pCi/L 44% of the EPA limit 15 pCi/L Main supplier: RAPID CITY · 72,009 people · 2018
Highest in the ZIP: 15.36 pCi/L — BOX ELDER · 14,000 people · 2017 | 8/11 | SYR4 |
| Lithium | 14 µg/L No EPA limit set Highest in the ZIP: BOX ELDER · 14,000 people · 2023 | 1/11 | UCMR-5 |
| Combined Uranium | 8.8735 µg/L 30% of the EPA limit 30 µg/L Highest in the ZIP: BOX ELDER · 14,000 people · 2017 | 1/11 | SYR4 |
| Arsenic | 6 µg/L 60% of the EPA limit 10 µg/L Main supplier: RAPID CITY · 72,009 people · 2019 | 1/11 | SYR4 |
| Lead | 4 µg/L 27% of the EPA limit 15 µg/L Main supplier: RAPID CITY · 72,009 people · 2018
Highest in the ZIP: 5.6 µg/L — RIMROCK HEIGHTS HOMEOWNERS ASSOCIATI · 35 people · 2019 | 10/11 | SYR4 |
| Chromium | 4.4 µg/L 4.4% of the EPA limit 100 µg/L Highest in the ZIP: BOX ELDER · 14,000 people · 2017 | 1/11 | SYR4 |
| Gross Beta Particle Activity | 3.5 pCi/L No EPA limit set Main supplier: RAPID CITY · 72,009 people · 2018 | 1/11 | SYR4 |
| Lead | 0.0060 mg/L 40% of the EPA limit 0.0150 mg/L Main supplier: RAPID CITY · 72,009 people · 2024
Highest in the ZIP: 0.0070 mg/L — WESTON HEIGHTS HOMEOWNERS ASSOCIATIO · 412 people · 2025 | 11/11 | LCR |
| PFHXS | 0.0056 µg/L No EPA limit set Main supplier: RAPID CITY · 72,009 people · 2025 | 1/11 | 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.
Water suppliers serving ZIP 57701
| Supplier | State | Population served |
|---|---|---|
| RAPID CITY | SD | 72,009 |
| BOX ELDER | SD | 14,000 |
| WESTON HEIGHTS HOMEOWNERS ASSOCIATIO | SD | 412 |
| AR RANCH | SD | 88 |
| SPEARFISH MEADOWS | SD | 87 |
| WHISPERING WILLOWS | SD | 64 |
| ELK VALLEY RANCHETTES | SD | 62 |
| ELK CREEK VALLEY VIEW ASSOC | SD | 52 |
| WEST NIKE SUBDIVISION | SD | 50 |
| CEDAR GULCH 2 | SD | 40 |
| RIMROCK HEIGHTS HOMEOWNERS ASSOCIATI | SD | 35 |
Frequently asked questions about ZIP 57701 tap water
Is the tap water in ZIP 57701 safe to drink?
EPA testing detected 17 contaminants across the water suppliers serving ZIP 57701. 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 57701?
11 public water suppliers report EPA drinking-water monitoring for ZIP 57701. Each is listed above with its population served.
What contaminants are in ZIP 57701's water?
EPA monitoring detected Nitrate, Fluoride, Barium, Copper, Nitrite, and others across this ZIP's suppliers. The full list with levels and sources is above.