Community Water System · PWS CA1210015
Willow Creek C.s.d.
Operator location Willow Creek, California - 71% of 7 violations are health-based (upper-third health share (> 23%)); surface water source; 1,298 served per SDWIS.
- 1,298
- People served (this PWS)
- 7
- EPA violations (this PWS)
- 5
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Willow Creek C.s.d. standing, low SDWIS violation third
71% of 7 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%). Population rank #17,213 of 29,740 among systems serving 500+.
The verdict
Willow Creek C.s.d. is in the lower third by violation count (7; 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 mid-pack at 1,298 (mid served population (≤ 3,309)). 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.
- #17,213 of 29,740
- Population · /systems
- #1,050 of 1,701
- Population · CA
- 7
- Total EPA violations on record
- 71%
- 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
- 940
- County
- Humboldt
- School/Daycare
- No
- MCL Violations
- 0
- Monitoring Violations
- 0
- Treatment Tech Violations
- 5
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Surface Water Treatment Rule | TT | 2 | 1993 |
| Revised Total Coliform Rule | TT | 2 | 2019 |
| LEAD AND COPPER RULE REVISIONS | RPT | 2 | 2025 |
| LEAD AND COPPER RULE REVISIONS | TT | 1 | 2024 |
Violation Count vs. the National Corpus
Willow Creek C.s.d. has 7 recorded EPA violations, 13% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 85% carry more. 71% of this system's own violations are health-based (5 of 7), and it ranks #17,213 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)
7 Among the lowest violation counts fewer violations than 85% 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 Willow Creek C.s.d.
5 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for CA1210015.
Sources: EPA SDWIS · California State Water Resources Control Board, Division of Drinking Water
Nationwide peers
7 violations · 1,298 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 near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Willow Creek C.s.d.
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.