Community Water System · PWS 084690475
Pine Ridge Water System
Operator location Pine Ridge, EPA Region 8 — Tribal Water Systems - larger served population (> 3,309) at 7,482 people served; 114 SDWIS violations on record from groundwater sources.
- 7,482
- People served (this PWS)
- 114
- EPA violations (this PWS)
- 23
- Health-based (this PWS)
- No PFAS
- UCMR5 (this PWS)
Pine Ridge Water System standing, high SDWIS violation third
7,482 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 20% is middle-third health share (≤ 23%). UCMR5: UCMR5 tested, none detected. Population rank #5,895 of 29,740 among systems serving 500+.
The verdict
Pine Ridge Water System sits in the upper third of the sitemap cohort by violation count (114), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (7,482; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 20% (middle-third health share (≤ 23%)). UCMR5 tested this system and reported no PFAS above the minimum reporting level.
- #5,895 of 29,740
- Population · /systems
- #2 of 55
- Population · 08
- 114
- Total EPA violations on record
- 20%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
System Details
- System Type
- Community
- Owner Type
- Native American
- Connections
- 1,151
- School/Daycare
- No
- MCL Violations
- 22
- Monitoring Violations
- 90
- Treatment Tech Violations
- 1
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MCL | 21 | 1999 |
| Coliform (TCR) | MR | 18 | 1997 |
| Barium | MR | 3 | 1996 |
| Cadmium | MR | 2 | 1996 |
| Arsenic | MR | 2 | 1996 |
| Fluoride | MR | 2 | 1996 |
| Chromium | MR | 2 | 1996 |
| Gross Alpha, Excl. Radon and U | MR | 2 | 1982 |
| Nitrate | MR | 2 | 1998 |
| Selenium | MR | 2 | 1996 |
| Mercury | MR | 2 | 1996 |
| Groundwater Rule | TT | 1 | 2018 |
| Combined Uranium | MCL | 1 | 2019 |
| CYANIDE | MR | 1 | 1996 |
| Heptachlor epoxide | MR | 1 | 1996 |
| o-Dichlorobenzene | MR | 1 | 1998 |
| Di(2-ethylhexyl) adipate | MR | 1 | 1996 |
| Benzo(a)pyrene | MR | 1 | 1996 |
| HEXACHLOROBENZENE | MR | 1 | 1996 |
| OXAMYL | MR | 1 | 1996 |
| Di(2-ethylhexyl) phthalate | MR | 1 | 1996 |
| 1,1-Dichloroethylene | MR | 1 | 1998 |
| CHLOROBENZENE | MR | 1 | 1998 |
| Xylenes, Total | MR | 1 | 1998 |
| Dinoseb | MR | 1 | 1996 |
| 1,1,1-Trichloroethane | MR | 1 | 1998 |
| 2,4,5-TP | MR | 1 | 1996 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 1 | 1996 |
| Simazine | MR | 1 | 1996 |
| Picloram | MR | 1 | 1996 |
Violation Count vs. the National Corpus
Pine Ridge Water System has 114 recorded EPA violations, 76% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 24% carry more. 20% of this system's own violations are health-based (23 of 114), and it ranks #5,895 of 29,740 by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
114 Higher than most more violations than 76% of 29,740 water systems
the national water-system corpus, bucketed by value
Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA SDWIS · 2026-05-15
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 174 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFMBA | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 9/19/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 9/19/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHpS | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 9/19/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 9/19/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| NFDHA | 9/19/2023 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFPeA | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFEESA | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| ADONA | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 9/19/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFTrDA | 9/19/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFPeS | 9/19/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFBS | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 9/19/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxA | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| NEtFOSAA | 9/19/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| 9Cl-PF3ONS | 9/19/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFTA | 9/19/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFOS | 9/19/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOA | 9/19/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFDoA | 9/19/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 9/19/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 9/19/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 9/19/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFTA | 7/26/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFTrDA | 7/26/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| NEtFOSAA | 7/26/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 7/26/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFTrDA | 7/12/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFTA | 7/12/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| NEtFOSAA | 7/12/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 7/12/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFNA | 7/12/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| 9Cl-PF3ONS | 7/12/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFUnA | 7/12/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 7/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 7/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 7/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| ADONA | 7/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOS | 7/12/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHpS | 7/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 7/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 7/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 7/12/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| NMeFOSAA | 7/12/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
Population served record for Pine Ridge Water System
EPA SDWIS lists 7,482 people served and 1,151 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
114 violations · 7,482 served: nearest cross-state SDWIS matches.
Cross-state systems with comparable violation load
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems with similar served population
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Pine Ridge Water System
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in EPA Region 8 — Tribal Water Systems compares on the same EPA violation measures. EPA Region 8 — Tribal Water Systems systems
- Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
- Find and compare another public water system by name or PWSID. Search systems
EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.