Community Water System · PWS SD4600145
Gregory
Operator location Gregory, South Dakota - upper-third violation load (> 74 violations) with 84 EPA violations; groundwater source; 1,221 served (PWS-level, not municipal population).
- 1,221
- People served (this PWS)
- 84
- EPA violations (this PWS)
- 4
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Gregory standing, high SDWIS violation third
84 EPA SDWIS violations on record - upper-third violation load (> 74 violations). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 5% is middle-third health share (≤ 23%). Population rank #17,657 of 29,740 among systems serving 500+.
The verdict
Gregory sits in the upper third of the sitemap cohort by violation count (84), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 1,221 (mid served population (≤ 3,309)). Health-based share is 5% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- #17,657 of 29,740
- Population · /systems
- #87 of 171
- Population · SD
- 84
- Total EPA violations on record
- 5%
- 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
- Local
- Connections
- 741
- County
- Gregory
- School/Daycare
- No
- MCL Violations
- 0
- Monitoring Violations
- 64
- Treatment Tech Violations
- 4
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Lead and Copper Rule | MR | 7 | 2005 |
| Gross Alpha, Excl. Radon and U | MR | 3 | 1988 |
| Combined Radium (-226 and -228) | MR | 3 | 1988 |
| Nitrate | MR | 3 | 1995 |
| Cadmium | MR | 2 | 1989 |
| Chromium | MR | 2 | 1989 |
| Mercury | MR | 2 | 1989 |
| Selenium | MR | 2 | 1989 |
| LASSO | MR | 2 | 1999 |
| Heptachlor | MR | 2 | 1999 |
| Heptachlor epoxide | MR | 2 | 1999 |
| Atrazine | MR | 2 | 1999 |
| Benzo(a)pyrene | MR | 2 | 1999 |
| Hexachlorocyclopentadiene | MR | 2 | 1999 |
| Endrin | MR | 2 | 1999 |
| Barium | MR | 2 | 1989 |
| Methoxychlor | MR | 2 | 1999 |
| Di(2-ethylhexyl) adipate | MR | 2 | 1999 |
| Total Polychlorinated Biphenyls (PCB) | MR | 2 | 1999 |
| Coliform (TCR) | MR | 2 | 1991 |
| Fluoride | MR | 2 | 1989 |
| HEXACHLOROBENZENE | MR | 2 | 1999 |
| BHC-GAMMA | MR | 2 | 1999 |
| Simazine | MR | 2 | 1999 |
| Chlordane | MR | 2 | 1999 |
| Di(2-ethylhexyl) phthalate | MR | 2 | 1999 |
| Arsenic | MR | 2 | 1989 |
| Toxaphene | MR | 2 | 1999 |
| Stage 1 Disinfectants and Disinfection Byproducts Rule | TT | 2 | 2004 |
| Groundwater Rule | TT | 2 | 2019 |
Violation Count vs. the National Corpus
Gregory has 84 recorded EPA violations, 69% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 30% carry more. 5% of this system's own violations are health-based (4 of 84), and it ranks #17,657 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)
84 Around the middle fewer violations than 30% 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
SDWIS compliance record for Gregory
84 violations on record for SD4600145; use EPA SDWIS to confirm return-to-compliance dates and monitoring categories.
Sources: EPA SDWIS
Nationwide peers
84 violations · 1,221 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 near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Gregory
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in South Dakota compares on the same EPA violation measures. South Dakota 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.