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States → EPA Region 9 — Tribal Water Systems

Community Water System · PWS 093200161

Washoe Tribe Carson Colony

Gardnerville, EPA Region 9 — Tribal Water Systems 89410 - drinking water served from groundwater sources to 450 people, tracked in EPA SDWIS and UCMR5.

450
People served
203
EPA violations
4
Health-based
Untested
UCMR5 result

The verdict

EPA records 203 drinking-water violations at Washoe Tribe Carson Colony, 2% of them health-based.

203
Total EPA violations on record
2%
Health-based (MCL / treatment failure)
450
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Washoe Tribe Carson Colony

Washoe Tribe Carson Colony is a native american-owned community water system that delivers drinking water to 450 residents in Gardnerville, EPA Region 9 — Tribal Water Systems through 93 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 203 total violations for this system , of which 4 (2%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 172 monitoring and reporting violations are on file. The most recent violation on record dates to 2023.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 14 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
450
Total Violations
203
Health-Based Violations
4
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Native American
Connections
93
School/Daycare
No
MCL Violations
3
Monitoring Violations
172
Treatment Tech Violations
1

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 14 2013
Nitrate MR 8 2023
Lead and Copper Rule MR 7 2017
2,3,7,8-TCDD MR 4 2020
Endrin MR 3 2011
BHC-GAMMA MR 3 2011
Methoxychlor MR 3 2011
Toxaphene MR 3 2011
Dalapon MR 3 2011
Diquat MR 3 2011
Endothall MR 3 2011
Glyphosate MR 3 2011
Di(2-ethylhexyl) adipate MR 3 2011
OXAMYL MR 3 2011
Simazine MR 3 2011
Di(2-ethylhexyl) phthalate MR 3 2011
Picloram MR 3 2011
Dinoseb MR 3 2011
Hexachlorocyclopentadiene MR 3 2011
Carbofuran MR 3 2011
Atrazine MR 3 2011
LASSO MR 3 2011
Heptachlor MR 3 2011
Heptachlor epoxide MR 3 2011
2,4-D MR 3 2011
2,4,5-TP MR 3 2011
HEXACHLOROBENZENE MR 3 2011
Benzo(a)pyrene MR 3 2011
Pentachlorophenol MR 3 2011
1,2-DIBROMO-3-CHLOROPROPANE MR 3 2011

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 Washoe Tribe Carson Colony.

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 093200161 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
2023 Nitrate MR 8 SDWIS / 093200161 / 1040
2020 2,3,7,8-TCDD MR 4 SDWIS / 093200161 / 2063
2019 Revised Total Coliform Rule RPT 1 SDWIS / 093200161 / 8000
2017 Lead and Copper Rule MR 7 SDWIS / 093200161 / 5000
2017 Groundwater Rule TT 1 SDWIS / 093200161 / 0700
2016 Revised Total Coliform Rule Other 1 SDWIS / 093200161 / 8000
2013 Coliform (TCR) MR 14 SDWIS / 093200161 / 3100
2013 Stage 2 Disinfectants and Disinfection Byproducts Rule MR 1 SDWIS / 093200161 / 0600
2013 Nitrate MCL 1 SDWIS / 093200161 / 1040
2012 Consumer Confidence Rule Other 3 SDWIS / 093200161 / 7000
2011 Endrin MR 3 SDWIS / 093200161 / 2005
2011 BHC-GAMMA MR 3 SDWIS / 093200161 / 2010
2011 Methoxychlor MR 3 SDWIS / 093200161 / 2015
2011 Toxaphene MR 3 SDWIS / 093200161 / 2020
2011 Dalapon MR 3 SDWIS / 093200161 / 2031

How Washoe Tribe Carson Colony Compares

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

Metric Washoe Tribe Carson Colony EPA Region 9 — Tribal Water Systems avg Federal benchmark
Total violations 203 - 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 450 - 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 Washoe Tribe Carson Colony water safe to drink? ▼
Washoe Tribe Carson Colony (PWS ID: 093200161) has 203 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 450 people using Groundwater sources.
How many people does Washoe Tribe Carson Colony serve? ▼
Washoe Tribe Carson Colony serves 450 people in Gardnerville, EPA Region 9 — Tribal Water Systems. It is a Native American-owned system using Groundwater water sources with 93 service connections.
What type of violations does Washoe Tribe Carson Colony have? ▼
Washoe Tribe Carson Colony has 203 total violations: 4 health-based violations (MCL exceedances or treatment failures), 172 monitoring/reporting violations, and 1 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Washoe Tribe Carson Colony water? ▼
No PFAS testing data is available for Washoe Tribe Carson Colony under the EPA's UCMR5 monitoring program.
What water source does Washoe Tribe Carson Colony use? ▼
Washoe Tribe Carson Colony 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.