Transient Non-Community Water System · PWS CA4910309
Csp-Fort Ross State Park
Operator location Mendocino, California - 94% of 17 violations are health-based (upper-third health share (> 23%)); surface water source; 3,501 served per SDWIS.
- 3,501
- People served (this PWS)
- 17
- EPA violations (this PWS)
- 16
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Csp-Fort Ross State Park standing, low SDWIS violation third
94% of 17 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 94% is upper-third health share (> 23%). Population rank #9,605 of 29,740 among systems serving 500+.
The verdict
Csp-Fort Ross State Park is in the lower third by violation count (17; lower-third violation load (≤ 21 violations)). A low count does not mean the system is unmonitored - monitoring and reporting violations still appear in SDWIS. Population served is large (3,501; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 94% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #9,605 of 29,740
- Population · /systems
- #728 of 1,701
- Population · CA
- 17
- Total EPA violations on record
- 94%
- 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
- Transient Non-Community
- Owner Type
- State
- Connections
- 28
- County
- Sonoma
- School/Daycare
- No
- MCL Violations
- 12
- Monitoring Violations
- 1
- Treatment Tech Violations
- 4
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Arsenic | MCL | 12 | 2018 |
| Surface Water Treatment Rule | TT | 4 | 1995 |
| Revised Total Coliform Rule | MON | 1 | 2021 |
Violation Count vs. the National Corpus
Csp-Fort Ross State Park has 17 recorded EPA violations, 28% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 71% carry more. 94% of this system's own violations are health-based (16 of 17), and it ranks #9,605 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)
17 Lower than most fewer violations than 71% 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 Csp-Fort Ross State Park
16 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for CA4910309.
Sources: EPA SDWIS · California State Water Resources Control Board, Division of Drinking Water
Nationwide peers
17 violations · 3,501 served: nearest cross-state SDWIS matches.
Cross-state systems with similarly light violation ledgers
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 Csp-Fort Ross State Park
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.