Transient Non-Community Water System · PWS CA1400037
Lone Pine Oasis
Operator location Valley Center, California - 71% of 251 violations are health-based (upper-third health share (> 23%)); groundwater source; 49 served per SDWIS.
- 49
- People served (this PWS)
- 251
- EPA violations (this PWS)
- 179
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Lone Pine Oasis standing, high SDWIS violation third
71% of 251 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 71% is upper-third health share (> 23%).
The verdict
Lone Pine Oasis sits in the upper third of the sitemap cohort by violation count (251), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (49; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 71% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- 251
- Total EPA violations on record
- 71%
- Health-based (MCL / treatment failure)
- 49
- 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
- Transient Non-Community
- Owner Type
- Private
- Connections
- 48
- County
- Inyo
- School/Daycare
- No
- MCL Violations
- 179
- Monitoring Violations
- 59
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Arsenic | MCL | 107 | 2022 |
| Combined Uranium | MCL | 57 | 2020 |
| Arsenic | MR | 23 | 2017 |
| Combined Uranium | MR | 18 | 2015 |
| Coliform (TCR) | MCL | 14 | 2013 |
| Lead and Copper Rule | MR | 5 | 2019 |
| TTHM | MR | 4 | 2015 |
| Total Haloacetic Acids (HAA5) | MR | 4 | 2015 |
| Nitrate | MR | 2 | 2014 |
| Gross Alpha, Excl. Radon and U | MR | 2 | 1981 |
| Coliform (TCR) | MR | 1 | 2015 |
| Fluoride | MCL | 1 | 1979 |
Violation Count vs. the National Corpus
Lone Pine Oasis has 251 recorded EPA violations, 88% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 12% carry more. 71% of this system's own violations are health-based (179 of 251), 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)
251 Higher than most more violations than 88% 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 Lone Pine Oasis
179 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for CA1400037.
Sources: EPA SDWIS · California State Water Resources Control Board, Division of Drinking Water
Nationwide peers
251 violations · 49 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.
What to do with Lone Pine Oasis
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.