Tapcensus

Chenega

Community water system in Chenega Bay, Alaska, serving 50 people from surface water. 5 rules violated in the past three years. Owned by tribal government.

People served 50 surface water
Rules violated, past 3 years 5 one rule can carry several violations
Unresolved 0 rules currently in violation, EPA data updated Oct 7, 2026
Quarters with violations 11 of the last 12 quarters

Quarterly compliance history

SQ3
2023
VQ4
2023
SQ1
2024
SQ2
2024
VQ3
2024
VQ4
2024
VQ1
2025
VQ2
2025
VQ3
2025
VQ4
2025
VQ1
2026
–Q2
2026
UQ3
2026
–No violation identified VViolation identified SSerious violator (EPA enforcement priority) UUndetermined Oldest quarter on the left. Quarters 1 to 12 are the twelve most recent official quarters at EPA's last data refresh; the 13th is the quarter in progress at that refresh, which EPA reports as undetermined.

Rules violated in the past three years

Jul to Sep 2023 to Jul to Sep 2026

Revised Total Coliform Rule

Monitoring Violation

13 violations, Nov 2023 to Mar 2026
EPA rule code 111 · 13 violations recorded

Monitoring Violation: 13 violations, Nov 2023 to Mar 2026. The system did not complete required monitoring. This does not show that a contaminant was found.

What the rule requires: The 2013 RTCR (effective 2016) replaced the original TCR. It triggers automatic E. coli testing whenever total coliform is found. A single E. coli-positive sample is an acute MCL violation. It also requires systems exceeding 5% total coliform-positive samples to conduct a formal assessment and correct any deficiencies, helping prevent contamination before it escalates.

About this rule

Interim and Long Term 1 Enhanced Surface Water Treatment Rule

Monitoring and Reporting

1 violation, Jan 2025 to Feb 2025 · Interim Enhanced Surface Water Treatment Rule
EPA rule code 122 · 1 violation recorded

Monitoring and Reporting: 1 violation, Jan 2025 to Feb 2025. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.

Contaminant on the record: Interim Enhanced Surface Water Treatment Rule.

Surface Water Treatment Rule

Monitoring and ReportingTreatment Technique Violation Health-based

20 violations, Aug 2023 to Mar 2026
EPA rule code 121 · 20 violations recorded, 5 health-based

Treatment Technique Violation, health-based: 5 violations, Aug 2023 to Aug 2024. The system did not carry out a required treatment process or corrective action.

Monitoring and Reporting: 15 violations, Nov 2023 to Mar 2026. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.

What the rule requires: All systems using surface water (rivers, lakes, reservoirs) or groundwater under surface influence (GWUDI) must filter and disinfect. Treatment technique violations mean the system failed to maintain adequate disinfectant residual, exceeded turbidity limits, or lacked required permits. Snowmelt and storm events can raise turbidity and pathogen loads in surface water.

Health effects: Without proper filtration/disinfection: Giardia lamblia (severe diarrhea, cramping), Cryptosporidium (life-threatening for immunocompromised individuals), viruses (hepatitis A, norovirus). Turbidity itself is not a health risk but can shield pathogens from disinfection. Limit: Treatment technique: turbidity ≤0.3 NTU in 95% of monthly samples; detectable disinfectant residual in 95% of distribution samples

About this rule

Stage 1 Disinfectants and Disinfection Byproducts Rule

Monitoring and Reporting

13 violations, Oct 2023 to Mar 2026 · Chlorine (MRDL)
EPA rule code 210 · 13 violations recorded

Monitoring and Reporting: 13 violations, Oct 2023 to Mar 2026. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.

Contaminant on the record: Chlorine (MRDL).

Stage 2 Disinfectants and Disinfection Byproducts Rule

Monitoring and Reporting

2 violations, Jan 2025 to Dec 2025 · 2 contaminants
EPA rule code 220 · 2 violations recorded

Monitoring and Reporting: 2 violations, Jan 2025 to Dec 2025. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.

Contaminants on the record: Total Haloacetic Acids (HAA5), TTHM (Total Trihalomethanes).

Lead and copper at the tap

The 90th percentile of the tap samples the system collected in its latest monitoring period, against EPA's action level. Levels vary between homes.

Lead 0.00154 mg/L

Action level 0.015 mg/L · Jan 2022 to Dec 2024

Copper 53.198 mg/L

Action level 1.3 mg/L · Jul to Dec 2011

About this data

Rules violated and the list above come from EPA's SDWIS violation records, one row per violation and contaminant, grouped by the rule each row belongs to. A violation counts when its non-compliance period ended on or after Jul 1, 2023, the start of the thirteen quarters ECHO's three-year figures cover, or is still open; it is unresolved when it was still open at EPA's data refresh on Oct 7, 2026. EPA's rule code 500, "Not Regulated", is left out, as in ECHO's counts. Each rule's violation count is EPA's, and one rule can carry several: a missed monitoring round for a group of contaminants is one violation per contaminant and period. Category names are EPA's violation categories.

ECHO's own summary count of rules violated agrees with this grouping for 98.8% of active systems nationally, and its count of rules being violated for 98.7%; where they differ, the figures here follow the rows listed.

A measured value shown with a rule is the sample result EPA recorded with that violation (SDWIS viol_measure), against the limit EPA recorded on the same row (state_mcl), both in EPA's unit as written; violations without a recorded value, such as missed monitoring, show none. Other measured contaminant levels are not part of this record; each system publishes them in its annual Consumer Confidence Report.

Lead and copper are the newest 90th-percentile results in EPA's SDWA data download (LCR_SAMPLES, codes PB90 and CU90): for each monitoring period a system reports the 90th-percentile value of its tap samples, which EPA compares with its action level of 0.015 mg/L for lead and 1.3 mg/L for copper (40 CFR 141.80). A result is not a measurement of any one tap.

Service area from EPA's Public Water System Service Area Boundaries dataset: State. The system's location is the centre of the service area EPA publishes for the system.

Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Alaska records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.