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States → EPA Region 9 — Tribal Water Systems

Community Water System · PWS 090400226

Greater Santa Rosa Regional

Sells, EPA Region 9 — Tribal Water Systems 85634 - drinking water served from groundwater sources to 1,623 people, tracked in EPA SDWIS and UCMR5.

1,623
People served
49
EPA violations
2
Health-based
Untested
UCMR5 result

The verdict

EPA records 49 drinking-water violations at Greater Santa Rosa Regional, 4% of them health-based.

49
Total EPA violations on record
4%
Health-based (MCL / treatment failure)
1,623
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Greater Santa Rosa Regional

Greater Santa Rosa Regional is a native american-owned community water system that delivers drinking water to 1,623 residents in Sells, EPA Region 9 — Tribal Water Systems through 296 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 49 total violations for this system , of which 2 (4%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 41 monitoring and reporting violations are on file. The most recent violation on record dates to 2017.

The most frequently cited contaminant at this system is Arsenic, recorded in 2 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

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
1,623
Total Violations
49
Health-Based Violations
2
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Native American
Connections
296
School/Daycare
No
MCL Violations
2
Monitoring Violations
41
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Arsenic MR 2 2017
Arsenic MCL 1 2007
Beryllium, Total MR 1 2004
Nitrate MR 1 2004
Asbestos MR 1 2004
Toxaphene MR 1 2004
Endrin MR 1 2004
Methoxychlor MR 1 2004
Dalapon MR 1 2004
Endothall MR 1 2004
Glyphosate MR 1 2004
Di(2-ethylhexyl) adipate MR 1 2004
OXAMYL MR 1 2004
Simazine MR 1 2004
Di(2-ethylhexyl) phthalate MR 1 2004
Picloram MR 1 2004
Atrazine MR 1 2004
2,3,7,8-TCDD MR 1 2004
Heptachlor MR 1 2004
Heptachlor epoxide MR 1 2004
2,4-D MR 1 2004
2,4,5-TP MR 1 2004
HEXACHLOROBENZENE MR 1 2004
Pentachlorophenol MR 1 2004
Total Polychlorinated Biphenyls (PCB) MR 1 2004
1,2-DIBROMO-3-CHLOROPROPANE MR 1 2004
ETHYLENE DIBROMIDE MR 1 2004
Combined Uranium MR 1 2013
Combined Radium (-226 and -228) MR 1 2013
Gross Alpha, Excl. Radon and U MR 1 2013

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 Greater Santa Rosa Regional.

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 090400226 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
2017 Arsenic MR 2 SDWIS / 090400226 / 1005
2013 Combined Uranium MR 1 SDWIS / 090400226 / 4006
2013 Combined Radium (-226 and -228) MR 1 SDWIS / 090400226 / 4010
2013 Gross Alpha, Excl. Radon and U MR 1 SDWIS / 090400226 / 4000
2007 Arsenic MCL 1 SDWIS / 090400226 / 1005
2004 Beryllium, Total MR 1 SDWIS / 090400226 / 1075
2004 Nitrate MR 1 SDWIS / 090400226 / 1040
2004 Asbestos MR 1 SDWIS / 090400226 / 1094
2004 Toxaphene MR 1 SDWIS / 090400226 / 2020
2004 Endrin MR 1 SDWIS / 090400226 / 2005
2004 Methoxychlor MR 1 SDWIS / 090400226 / 2015
2004 Dalapon MR 1 SDWIS / 090400226 / 2031
2004 Endothall MR 1 SDWIS / 090400226 / 2033
2004 Glyphosate MR 1 SDWIS / 090400226 / 2034
2004 Di(2-ethylhexyl) adipate MR 1 SDWIS / 090400226 / 2035

How Greater Santa Rosa Regional Compares

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

Metric Greater Santa Rosa Regional EPA Region 9 — Tribal Water Systems avg Federal benchmark
Total violations 49 - SDWA compliance, any non-zero count is a recorded breach
Health-based violations 2 - Indicates a contaminant exceeded a federal MCL
PFAS detection None - EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 1,623 - 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 Greater Santa Rosa Regional water safe to drink? ▼
Greater Santa Rosa Regional (PWS ID: 090400226) has 49 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 1,623 people using Groundwater sources.
How many people does Greater Santa Rosa Regional serve? ▼
Greater Santa Rosa Regional serves 1,623 people in Sells, EPA Region 9 — Tribal Water Systems. It is a Native American-owned system using Groundwater water sources with 296 service connections.
What type of violations does Greater Santa Rosa Regional have? ▼
Greater Santa Rosa Regional has 49 total violations: 2 health-based violations (MCL exceedances or treatment failures), 41 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Greater Santa Rosa Regional water? ▼
No PFAS testing data is available for Greater Santa Rosa Regional under the EPA's UCMR5 monitoring program.
What water source does Greater Santa Rosa Regional use? ▼
Greater Santa Rosa Regional uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
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. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

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.