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States → EPA Region 9 — Tribal Water Systems

Community Water System · PWS 090605118

Redwood Valley Rancheria

Redwood Valley, EPA Region 9 — Tribal Water Systems 95470 - drinking water served from surface water sources to 152 people, tracked in EPA SDWIS and UCMR5.

152
People served
128
EPA violations
1
Health-based
Untested
UCMR5 result

The verdict

EPA records 128 drinking-water violations at Redwood Valley Rancheria, 1% of them health-based.

128
Total EPA violations on record
1%
Health-based (MCL / treatment failure)
152
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Redwood Valley Rancheria

Redwood Valley Rancheria is a native american-owned community water system that delivers drinking water to 152 residents in Redwood Valley, EPA Region 9 — Tribal Water Systems through 33 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 128 total violations for this system , of which 1 (1%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 45 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 27 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
152
Total Violations
128
Health-Based Violations
1
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Native American
Connections
33
School/Daycare
No
MCL Violations
0
Monitoring Violations
45
Treatment Tech Violations
1

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 27 2015
Chlorine MR 6 2024
Revised Total Coliform Rule MON 4 2024
Lead and Copper Rule MR 4 2007
Consumer Confidence Rule Other 4 2023
Total Haloacetic Acids (HAA5) MR 2 2015
TTHM MR 2 2015
Groundwater Rule TT 1 2023

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 Redwood Valley 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 090605118 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
2024 Chlorine MR 6 SDWIS / 090605118 / 0999
2024 Revised Total Coliform Rule MON 4 SDWIS / 090605118 / 8000
2023 Consumer Confidence Rule Other 4 SDWIS / 090605118 / 7000
2023 Groundwater Rule TT 1 SDWIS / 090605118 / 0700
2015 Coliform (TCR) MR 27 SDWIS / 090605118 / 3100
2015 Total Haloacetic Acids (HAA5) MR 2 SDWIS / 090605118 / 2456
2015 TTHM MR 2 SDWIS / 090605118 / 2950
2007 Lead and Copper Rule MR 4 SDWIS / 090605118 / 5000

How Redwood Valley Rancheria Compares

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

Metric Redwood Valley Rancheria EPA Region 9 — Tribal Water Systems avg Federal benchmark
Total violations 128 - SDWA compliance, any non-zero count is a recorded breach
Health-based violations 1 - Indicates a contaminant exceeded a federal MCL
PFAS detection None - EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 152 - 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 Redwood Valley Rancheria water safe to drink? ▼
Redwood Valley Rancheria (PWS ID: 090605118) has 128 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 152 people using Surface Water sources.
How many people does Redwood Valley Rancheria serve? ▼
Redwood Valley Rancheria serves 152 people in Redwood Valley, EPA Region 9 — Tribal Water Systems. It is a Native American-owned system using Surface Water water sources with 33 service connections.
What type of violations does Redwood Valley Rancheria have? ▼
Redwood Valley Rancheria has 128 total violations: 1 health-based violations (MCL exceedances or treatment failures), 45 monitoring/reporting violations, and 1 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Redwood Valley Rancheria water? ▼
No PFAS testing data is available for Redwood Valley Rancheria under the EPA's UCMR5 monitoring program.
What water source does Redwood Valley Rancheria use? ▼
Redwood Valley Rancheria uses Surface Water 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.