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Non-Transient Non-Community Water System · PWS 090600127

Dry Creek Rancheria

Geyserville, EPA Region 9 — Tribal Water Systems 95441 - drinking water served from groundwater sources to 2,200 people, tracked in EPA SDWIS and UCMR5.

2,200
People served
122
EPA violations
4
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 122 drinking-water violations at Dry Creek Rancheria, 3% of them health-based.

122
Total EPA violations on record
3%
Health-based (MCL / treatment failure)
2,200
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Dry Creek Rancheria

Dry Creek Rancheria is a native american-owned non-transient non-community water system that delivers drinking water to 2,200 residents in Geyserville, EPA Region 9 — Tribal Water Systems through 3 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 122 total violations for this system , of which 4 (3%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 44 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 11 violations (MR). This system was sampled under EPA's UCMR5 PFAS monitoring program and no PFAS compounds were detected above the minimum reporting level.

EPA Region 9 — Tribal Water Systems has thousands of regulated public water systems tracked by EPA under the Safe Drinking Water Act.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
2,200
Total Violations
122
Health-Based Violations
4
Water Source
Groundwater

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

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

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Dry Creek Rancheria.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID 090600127 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

EPA Region 9 — Tribal Water Systems Drinking Water Authority

EPA Region 9 — Tribal Water Systems's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find 09 regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2025 Chlorine MR 1 SDWIS / 090600127 / 0999
2021 Xylenes, Total MR 2 SDWIS / 090600127 / 2955
2019 E. COLI MR 1 SDWIS / 090600127 / 3014
2018 Revised Total Coliform Rule MON 1 SDWIS / 090600127 / 8000
2018 Public Notice Other 1 SDWIS / 090600127 / 7500
2017 Di(2-ethylhexyl) adipate MR 1 SDWIS / 090600127 / 2035
2017 Pentachlorophenol MR 1 SDWIS / 090600127 / 2326
2017 2,4-D MR 1 SDWIS / 090600127 / 2105
2017 Benzo(a)pyrene MR 1 SDWIS / 090600127 / 2306
2017 Picloram MR 1 SDWIS / 090600127 / 2040
2017 Methoxychlor MR 1 SDWIS / 090600127 / 2015
2017 Dinoseb MR 1 SDWIS / 090600127 / 2041
2017 2,4,5-TP MR 1 SDWIS / 090600127 / 2110
2017 Dalapon MR 1 SDWIS / 090600127 / 2031
2017 Di(2-ethylhexyl) phthalate MR 1 SDWIS / 090600127 / 2039

How Dry Creek Rancheria Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Dry Creek Rancheria EPA Region 9 — Tribal Water Systems avg Federal benchmark
Total violations 122 - SDWA compliance, any non-zero count is a recorded breach
Health-based violations 4 - Indicates a contaminant exceeded a federal MCL
PFAS detection None - EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 2,200 - Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across all regulated public water systems in EPA Region 9 — Tribal Water Systems.

Federal MCL reference, Safe Drinking Water Act thresholds
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Dry Creek Rancheria water safe to drink?
Dry Creek Rancheria (PWS ID: 090600127) has 122 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 2,200 people using Groundwater sources.
How many people does Dry Creek Rancheria serve?
Dry Creek Rancheria serves 2,200 people in Geyserville, EPA Region 9 — Tribal Water Systems. It is a Native American-owned system using Groundwater water sources with 3 service connections.
What type of violations does Dry Creek Rancheria have?
Dry Creek Rancheria has 122 total violations: 4 health-based violations (MCL exceedances or treatment failures), 44 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Dry Creek Rancheria water?
No. Dry Creek Rancheria was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does Dry Creek Rancheria use?
Dry Creek Rancheria uses Groundwater as its primary water source. It is classified as a Non-Transient Non-Community Water System, serving the same people for at least 6 months per year.
Where does this data come from?
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.
Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.