Non-Transient Non-Community Water System · PWS 090600127
Dry Creek Rancheria
Operator location Geyserville, EPA Region 9 — Tribal Water Systems - upper-third violation load (> 74 violations) with 122 EPA violations; groundwater source; 2,200 served (PWS-level, not municipal population).
- 2,200
- People served (this PWS) Middle third of systems
- 122
- EPA violations (this PWS) Upper third of systems
- 4
- Health-based (this PWS) Middle third by health-based share
- No PFAS
- UCMR5 (this PWS) Tested, none detected
Dry Creek Rancheria standing, high SDWIS violation third
122 EPA SDWIS violations on record - upper-third violation load (> 74 violations). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 3% is middle-third health share (≤ 23%). UCMR5: UCMR5 tested, none detected. Population rank #12,837 of 29,740 among systems serving 500+.
The verdict
Dry Creek Rancheria sits in the upper third of the sitemap cohort by violation count (122), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 2,200 (mid served population (≤ 3,309)). Health-based share is 3% (middle-third health share (≤ 23%)). UCMR5 tested this system and reported no PFAS above the minimum reporting level.
- #12,837 of 29,740
- Population · /systems
- #60 of 129
- Population · 09
- 122
- Total EPA violations on record
- 3%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.
System Details
- System Type
- Non-Transient Non-Community
- Owner Type
- Native American
- Connections
- 3
- School/Daycare
- No
- MCL Violations
- 4
- Monitoring Violations
- 44
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 11 | 2014 |
| Nitrate | MR | 4 | 2013 |
| Coliform (TCR) | MCL | 4 | 2011 |
| Consumer Confidence Rule | Other | 3 | 2002 |
| Xylenes, Total | MR | 2 | 2021 |
| Lead and Copper Rule | MR | 2 | 1996 |
| Arsenic | MR | 1 | 2001 |
| Cadmium | MR | 1 | 2001 |
| CYANIDE | MR | 1 | 1998 |
| Fluoride | MR | 1 | 2001 |
| Mercury | MR | 1 | 2001 |
| Selenium | MR | 1 | 2001 |
| Antimony, Total | MR | 1 | 2001 |
| Beryllium, Total | MR | 1 | 2001 |
| Di(2-ethylhexyl) adipate | MR | 1 | 2017 |
| Pentachlorophenol | MR | 1 | 2017 |
| 2,4-D | MR | 1 | 2017 |
| Benzo(a)pyrene | MR | 1 | 2017 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 1 | 1996 |
| Chlorine | MR | 1 | 2025 |
| Revised Total Coliform Rule | MON | 1 | 2018 |
| Public Notice | Other | 1 | 2018 |
| Picloram | MR | 1 | 2017 |
| Methoxychlor | MR | 1 | 2017 |
| Dinoseb | MR | 1 | 2017 |
| E. COLI | MR | 1 | 2019 |
| Barium | MR | 1 | 2001 |
| 2,4,5-TP | MR | 1 | 2017 |
| Dalapon | MR | 1 | 2017 |
| Chromium | MR | 1 | 2001 |
Violation Count vs. the National Corpus
Dry Creek Rancheria has 122 recorded EPA violations, 77% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 23% carry more. 3% of this system's own violations are health-based (4 of 122), and it ranks #12,837 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)
122 Higher than most more violations than 77% 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
How many violations vs. how serious, among peer systems
Dry Creek Rancheria plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.
Violation volume vs. health-based share
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 58 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFUnA | 7/22/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 7/22/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFOA | 7/22/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 7/22/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFDoA | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 7/22/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| ADONA | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTrDA | 7/22/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| NEtFOSAA | 7/22/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFNA | 7/22/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFMPA | 7/22/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| NMeFOSAA | 7/22/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| 9Cl-PF3ONS | 7/22/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxS | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpS | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 7/22/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| NFDHA | 7/22/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFEESA | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 7/22/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 7/22/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 7/22/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| HFPO-DA | 7/22/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMBA | 7/22/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOS | 1/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFNA | 1/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxS | 1/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 1/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 1/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NMeFOSAA | 1/6/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| NEtFOSAA | 1/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTrDA | 1/6/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFOA | 1/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFPeA | 1/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 1/6/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| NFDHA | 1/6/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| 8:2 FTS | 1/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFDA | 1/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 1/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFEESA | 1/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 1/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 1/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 4:2 FTS | 1/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 1/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 1/6/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
SDWIS compliance record for Dry Creek Rancheria
122 violations on record for 090600127; use EPA SDWIS to confirm return-to-compliance dates and monitoring categories.
Sources: EPA SDWIS
Nationwide peers
122 violations · 2,200 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 near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Dry Creek Rancheria
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in EPA Region 9 — Tribal Water Systems compares on the same EPA violation measures. EPA Region 9 — Tribal Water Systems 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.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.