Tapcensus

La Posta Upper

Community water system in California, serving 73 people from ground water. 4 rules violated in the past three years. Owned by tribal government.

People served 73 ground water
Rules violated, past 3 years 4 one rule can carry several violations
Unresolved 0 rules still in violation, EPA data updated Oct 7, 2026
Quarters with violations 3 of the last 12 quarters

Quarterly compliance history

–Q3
2023
–Q4
2023
–Q1
2024
–Q2
2024
VQ3
2024
–Q4
2024
–Q1
2025
–Q2
2025
VQ3
2025
–Q4
2025
SQ1
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

1 violation, Aug 2024 to Sep 2024
EPA rule code 111 · 1 violation recorded

Monitoring Violation: 1 violation, Aug 2024 to Sep 2024. 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

Stage 1 Disinfectants and Disinfection Byproducts Rule

Monitoring and Reporting

1 violation, Jul 2024 to Sep 2024 · Chlorine (MRDL)
EPA rule code 210 · 1 violation recorded

Monitoring and Reporting: 1 violation, Jul 2024 to Sep 2024. 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).

Nitrate Rule

Maximum Contaminant Level Violation Health-based

1 violation, Jan 2026 to Mar 2026 · 10.5 MG/L
EPA rule code 331 · 1 violation recorded, 1 health-based

Maximum Contaminant Level Violation, health-based: 1 violation, Jan 2026 to Mar 2026. A sample exceeded the maximum contaminant level EPA allows in drinking water.

Measured
Nitrate 10.5 MG/L

Jan to Mar 2026

What the rule requires: Nitrate (NO₃) is the most common chemical contaminant in US groundwater, entering from fertilizers, septic systems, and animal waste. It is odorless and tasteless — the only way to know if it's present is to test.

Health effects: Methemoglobinemia in infants under 6 months: gut bacteria convert nitrate to nitrite, which blocks oxygen transport in blood. Pregnant women should also take precautions. Chronic adult exposure at elevated levels may increase cancer risk. Limit: 10 mg/L as nitrogen (NO₃-N)

About this rule

Radionuclides and Revised Rad Rule

Monitoring and Reporting

5 violations, Jul 2025 to Jun 2026 · 3 contaminants
EPA rule code 340 · 5 violations recorded

Monitoring and Reporting: 5 violations, Jul 2025 to Jun 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.

Contaminants on the record: Gross Alpha, Excl. Radon and U, Combined Uranium, Combined Radium (-226 and -228).

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 0.0024 mg/L

Action level 0.015 mg/L · Jan 2023 to Dec 2025

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), retrieved on Oct 12, 2026: 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.

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 California 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. Retrieved from ECHO on Oct 11, 2026.