Community Water System · PWS SD4600224
New Underwood
Operator location New Underwood, South Dakota - 72% of 144 violations are health-based (upper-third health share (> 23%)); groundwater source; 679 served per SDWIS.
- 679
- People served (this PWS)
- 144
- EPA violations (this PWS)
- 104
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
New Underwood standing, high SDWIS violation third
72% of 144 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 72% is upper-third health share (> 23%). Population rank #24,754 of 29,740 among systems serving 500+.
The verdict
New Underwood sits in the upper third of the sitemap cohort by violation count (144), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (679; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 72% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #24,754 of 29,740
- Population · /systems
- #142 of 171
- Population · SD
- 144
- Total EPA violations on record
- 72%
- 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
- 269
- County
- Pennington
- School/Daycare
- No
- MCL Violations
- 104
- Monitoring Violations
- 27
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Gross Alpha, Excl. Radon and U | MCL | 52 | 2010 |
| Combined Radium (-226 and -228) | MCL | 40 | 2010 |
| Coliform (TCR) | MCL | 12 | 1997 |
| Toluene | MR | 5 | 2009 |
| Combined Radium (-226 and -228) | MR | 4 | 2003 |
| Gross Alpha, Excl. Radon and U | MR | 4 | 2003 |
| Combined Uranium | MR | 3 | 2003 |
| Thallium, Total | MR | 3 | 1995 |
| Antimony, Total | MR | 3 | 1995 |
| Chlorine | MR | 3 | 2022 |
| Revised Total Coliform Rule | MON | 2 | 2022 |
Violation Count vs. the National Corpus
New Underwood has 144 recorded EPA violations, 80% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 20% carry more. 72% of this system's own violations are health-based (104 of 144), and it ranks #24,754 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)
144 Higher than most more violations than 80% 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
Health-based violations on New Underwood
104 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for SD4600224.
Sources: EPA SDWIS
Nationwide peers
144 violations · 679 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 smaller service footprints
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with New Underwood
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.