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Lake Nacimiento, CA Tap Water Quality 2026

Water quality report for Lake Nacimiento, CA — PFAS, lead and copper results, violation history and state inspection findings from EPA SDWIS.

A look at Lake Nacimiento's drinking water using EPA enforcement records: violations, lead and copper results, PFAS sampling and state inspection findings.

Main Utility: Heritage Ranch Csd PWSID: CA4010012 Updated: 2026 Q2
✅

No federal limits exceeded on record

Lead was not detected and no violations are open. No PFAS was detected.

B

Lake Nacimiento earns a B for water quality

Graded on violations, lead, and PFAS, with state inspection findings.

Lead: not detected
PFAS tested, none detected
15 violations since 2015, 15 health-based
No violations currently open
Lake Nacimiento's lead level vs. all California community water systems
0 ppb5 ppb10 ppb15 ppb
Lead level: Not detected — 0% of the federal action level
✓ Lower lead than % of California utilities
Population Served
2956
~1963 connections
Water Source
Surface water
Drawn from surface water — SDWIS source code SW
Active Violations
0
15 since 2015, all resolved

Lead & Copper Testing

Lead (Pb)
90th percentile of tap samples collected across the distribution system
0% of EPA action level
Not detected
Action level: 15 ppb
Lead was not detected at the 90th percentile — the result fell below the laboratory detection limit. That is not the same as an absence of lead in every tap, and older homes with lead service lines can still show higher readings.

Contaminant Violations (2015–Present)

ContaminantTypeMeasuredLimitPeriodStatus
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.062 MG/L 0.060 mg/L 2024 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.067 MG/L 0.060 mg/L 2023 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.076 MG/L 0.060 mg/L 2023 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.082 MG/L 0.060 mg/L 2023 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.097 MG/L 0.060 mg/L 2023 Resolved
TTHM MCL EXCEEDANCE 0.082 MG/L 0.080 mg/L 2023 Resolved
TTHM MCL EXCEEDANCE 0.086 MG/L 0.080 mg/L 2022 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.113 MG/L 0.060 mg/L 2022 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.093 MG/L 0.060 mg/L 2022 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.083 MG/L 0.060 mg/L 2022 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.074 MG/L 0.060 mg/L 2020 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.079 MG/L 0.060 mg/L 2020 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.078 MG/L 0.060 mg/L 2020 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.0701 MG/L 0.060 mg/L 2020 Resolved
Total Haloacetic Acids (HAA5) MCL EXCEEDANCE 0.067 MG/L 0.060 mg/L 2019 Resolved
Understanding violation types MCL violations mean a contaminant exceeded the federal maximum limit — the most serious type.
TT (Treatment Technique) violations mean required treatment procedures weren't followed, but don't necessarily mean contamination occurred.

Violation History

15 violations are on record since 2015, of which 15 were health-based. All have been resolved and none remain open.

About the Main Water System

Utility Heritage Ranch Csd
PWSID CA4010012
Water source Surface water — Drawn from surface water — SDWIS source code SW
Population served 2,956
Service connections 1,963
Systems serving this area 1
Regulator State primacy agency
Data through 2026 Q2 — EPA SDWIS

Frequently Asked Questions

Is Lake Nacimiento tap water safe to drink? ▼
No federal limit is exceeded on record. No violations are currently open.
Does Lake Nacimiento water have PFAS? ▼
It was tested for the six regulated PFAS compounds and none were detected.
Who supplies water to Lake Nacimiento? ▼
Heritage Ranch Csd (PWSID CA4010012). Surface water. Drawn from surface water — SDWIS source code SW
When was this system last inspected? ▼
It was last inspected on 2025-04-30. No significant deficiencies were recorded.

What Should Lake Nacimiento Residents Do?

1
Read your annual water report
Your supplier publishes a Consumer Confidence Report each July covering the prior year.
2
Check for a lead service line
Lead reaches tap water mainly through service lines and household plumbing. Suppliers now publish an inventory identifying lead lines.
3
Flush before drinking
If water has sat in pipes more than six hours, run the cold tap for two minutes before drinking or cooking.

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