Community Water System · PWS CA5610702
U.s.n., San Nicolas Island
Operator location Point Mugu, California - 33% of 24 violations are health-based (upper-third health share (> 23%)); surface water source; 254 served per SDWIS.
- 254
- People served (this PWS)
- 24
- EPA violations (this PWS)
- 8
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
U.s.n., San Nicolas Island standing, mid SDWIS violation third
33% of 24 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 33% is upper-third health share (> 23%).
The verdict
U.s.n., San Nicolas Island lands in the middle third by violation volume (24), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (254; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 33% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- 24
- Total EPA violations on record
- 33%
- Health-based (MCL / treatment failure)
- 254
- People served by this PWS (SDWIS)
- N/A
- PFAS compounds detected (UCMR5)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
System Details
- System Type
- Community
- Owner Type
- Federal
- Connections
- 106
- County
- Ventura
- School/Daycare
- No
- MCL Violations
- 6
- Monitoring Violations
- 14
- Treatment Tech Violations
- 2
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 12 | 2003 |
| Coliform (TCR) | MCL | 4 | 2003 |
| TTHM | MCL | 2 | 2005 |
| Surface Water Treatment Rule | MR | 2 | 2012 |
| Surface Water Treatment Rule | TT | 2 | 1993 |
Violation Count vs. the National Corpus
U.s.n., San Nicolas Island has 24 recorded EPA violations, 36% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 63% carry more. 33% of this system's own violations are health-based (8 of 24), and it ranks unranked by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
24 Lower than most fewer violations than 63% 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 U.s.n., San Nicolas Island
8 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for CA5610702.
Sources: EPA SDWIS · California State Water Resources Control Board, Division of Drinking Water
Nationwide peers
24 violations · 254 served: nearest cross-state SDWIS matches.
Cross-state systems near this violation count
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
What to do with U.s.n., San Nicolas Island
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in California compares on the same EPA violation measures. California 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.